Protein: The Facts, the Myths, and the Real Science

Everyone has an opinion about protein, and the myths surrounding it are rampant. That's why sorting the facts from the crap will lead to better choices regarding your own diet and protein intake. Answer the questions below and see if you've been falling for the myths.

Fact or Myth?

The RDA (Recommended Dietary Allowance) protein suggestions are just fine for people who work out.

Hint: The RDA guideline for protein is 0.8 grams per kilogram of bodyweight per day. So if you weigh 190 pounds (86 kilograms) you'd need about 69 grams of protein.

The Answer: Lifters and athletes concerned with their performance or physique require more protein than what's recommended by the RDA. So it's a myth (and a joke) that the RDA protein recommendations are adequate for ass-kicking individuals.

Here's Why: RDA protein recommendations are too low for certain groups. Those recommendations were never intended for people attempting to enhance performance, maintain, or gain muscle. In fact, a higher protein intake may have positive benefits regarding different health ailments including obesity, type 2 diabetes, osteoporosis, heart disease and muscle wasting.

The RDA guideline reflects the minimum daily needs of protein required to maintain short-term nitrogen balance in healthy, moderately active people. Nitrogen balance compares the amount of nitrogen coming into the body (from dietary protein) to the amount being lost. It's often used as a measurement of protein balance since protein is 16 percent nitrogen.

If you're consuming the same amount of nitrogen that you're losing, you're in nitrogen balance. If you're consuming more than you're losing, you're in positive nitrogen balance. If you're losing more than you're consuming, you're in negative nitrogen balance and are losing protein.

Nitrogen balance studies often involve examining urinary nitrogen levels. Approximately 90 percent of the nitrogen in urine is urea and ammonia salts – the end products of protein metabolism. The remaining nitrogen is accounted for by other nitrogen-containing compounds.

This nitrogen balance method is useful, but it has problems: Urine collections tend to underestimate nitrogen losses, dietary intake tends to be overestimated, miscellaneous skin and hair losses are prone to error, and the response to increased protein intake varies tremendously.

The Really Geeky Stuff

  1. In a review published in the International Journal of Sports Nutrition, researchers concluded, "Those involved in strength training might need to consume as much as 1.6 to 1.7 grams of protein per kilogram per day (approximately twice the current RDA) while those undergoing endurance training might need about 1.2 to 1.6 grams per kilogram per day (approximately 1.5 times the current RDA)."
  2. In another article published in Nutrition & Metabolism, researcher Donald Layman argued that the dietary guidelines should be improved and reflect new understandings about protein requirements. According to him, "During the past decade a growing body of research reveals that dietary protein intakes above the RDA are beneficial in maintaining muscle function and mobility." Diets with increased protein have been shown to improve adult health when it comes to treatment or prevention of obesity, type 2 diabetes, osteoporosis, heart disease and muscle wasting.
  3. A review published in the International Journal of Sport Nutrition and Exercise Metabolism was conducted to evaluate the effects of dietary protein on body composition in energy-restricted resistance-trained athletes, and to provide protein recommendations for these athletes.

The researchers concluded that "...the range of 2.3 to 3.1 grams per kilogram of FFM (fat free mass) is the most consistently protective intake against losses of lean tissue." In other words, for every kilogram on your body that's not fat, you should be consuming 2-3 grams of protein in order to preserve lean tissue. So if you have 190 pounds of lean tissue, up to 258 grams of protein would be optimal for you.

In addition, the goal of the athlete should be considered. Leaner athletes or those having a primary goal of maintaining maximal FFM should aim toward intakes approaching the higher end of this range. Even higher levels of protein than those recommended in the review are not uncommon in exercising individuals. It's unlikely that negative health consequences will follow from higher levels of intake, assuming there are no related health problems that would suggest limiting intake.

Fact or Myth?

The thermic effect of protein is the same as it is for carbs and fat.

Hint: The thermic effect of feeding or diet induced thermogenesis (DIT) is the amount of energy your body has to expend in order to digest and assimilate food. So picture a lean chicken breast (mostly protein), a bowl of rice (mostly carb), and tablespoon of butter (mostly fat). Which do you think your body will have to work hardest to digest?

The Answer: Among the three macronutrients, protein ranks highest in diet induced thermogenesis. So it's a myth that they're all equal in terms of their thermic effect. That means it'll cost you more calories to digest and absorb protein than it would fat and carbohydrate.

Here's Why: The consumption of protein requires an expenditure of 20-30% of the calories derived from protein. So, if 200 calories of protein are eaten, 40-60 calories are burned during digestion. DIT from carbohydrate is 15-20% and 2-5% for fat.

Fact or Myth?

Protein is more satiating (filling) than fat or carbohydrate.

Hints: Protein has an influence on CCK (cholecystokinin) and ghrelin. Protein may stimulate cholecystokinin (CCK) and decrease ghrelin. CCK is secreted mostly from the inner layer of the gastrointestinal tract has been shown to act as a satiety signal. The satiating effect of CCK was first demonstrated when administering CCK to rats. It "dose dependently" reduced meal size. Ghrelin is produced primarily in the stomach and has appetite increasing properties. Ghrelin levels are relatively high prior to a meal and they decrease after a meal.

The Answer: It's a fact that protein is usually more satiating than fat or carbs. When comparing protein, fat, and carbohydrate, protein is generally reported as the most satiating (satisfying to a point of full or beyond) and fat as the least satiating.

Here's Why: Research indicates that one of the primary factors involved with the satiating effects of protein is the thermic effect of feeding, mentioned above. Though protein's influence on ghrelin and CCK may play a large role in its satiating effects, more research needs to be conducted in these areas, as findings have been indecisive. Future research should concentrate on different levels of protein, different types of protein, and consumption of proteins in short and long term.

The Really Geeky Stuff

  1. A review published in Nutrition & Metabolism reported that protein induced thermogenesis has an important effect on satiety. "Protein plays a key role in body weight regulation through satiety related to diet-induced thermogenesis."
  2. A study published in Physiology & Behavior investigated the relative satiating effect of the macronutrients in lean women. On four separate occasions, the composition of an iso-caloric lunch "preload" was controlled in 12 lean women. Macronutrient composition had a significant effect on short-term hunger – the women were less hungry after the protein preload compared to the preloads with the other macronutrients. They also ate less after the protein preload.
  3. A study published in the American Journal of Clinical Nutrition tested the prediction that increasing protein while maintaining the carb content of a diet lowers body weight due to decreased appetite and decreased calorie intake. The study showed when increasing the protein intake from 15% of diet to 30% of diet (while eating the same amount of carbs) there was a decrease in appetite and fewer calories were consumed.
  4. The Journal of Clinical Endocrinology & Metabolism published a study that compared the effect of different proteins and carbohydrates on indicators of appetite and appetite regulatory hormones. CCK level was one of the primary outcomes measured.

Calorie intake was higher after the glucose preload compared with lactose and protein preloads. CCK level was higher 90 minutes after the protein preloads compared with glucose and lactose level. Researchers concluded that "acute appetite and energy intake are equally reduced after consumption of lactose, casein, or whey compared with glucose."

One Quick Caveat

The research sometimes gets a little messy. For example, some studies are indecisive when it comes to protein intake and ghrelin levels. This is why you need to rely on your own reasoning, logic, and experience while gathering info from the research.

References

  1. Blom, A.M., Lluch, A., Stafleu, A., Vinoy, S., Holst, J., Schaafsma, G., & Hendriks, H. (2006). Effect of high-protein breakfast ont he postprandial ghrelin response. The American Journal of Clinical Nutrition, 83(2), 211-220.
  2. Bowen, J., Noakes, M., Trenerry, C., & Clifton, P.M. (2006).Energy intake, Ghrelin, and Cholecystokinin after Different Carbohydrate and Protein Preloads in Overweight Men. The Journal of Clinical Endocrinology & Metabolism, 91(4).
  3. Helms, E., Zinn, C., Rowlands, D.S., & Brown, S.R. (2014). A Systematic Review of Dietary Protein During Caloric Restriction in Resistance Trained Lean Athletes: A Case for Higher Intakes. International Journal of Sport Nutrition and Exercise Metabolism, 24, 127-138.
  4. Layman, D.K.(2009). Dietary Guidelines should reflect new understandings about adult protein needs. Nutrition & Metabolism, 6(12), Lemon, P. (1998). Effects of exercise on dietary protein requirements. International Journal of Sports Nutrition, 8(4), 426-447.
  5. Lucas, M, & Heiss C.J.(2005) Protein needs of older adults engaged in resistance training: A review. Journal of Aging and Physical Activity, 13(2), 223-236.
  6. Moran, L.J., Luscombe-Marsh, N.D., Noakes, M., Wittert, G.A., Keogh, J.B., & Clifton, P.M. (2005). The Satiating Effect of Dietary Protein Is Unrelated to Postprandial Ghrelin. The Journal of Clinical Endocrinology & Metabolsim, 90(9).
  7. Poppitt, S.D., McCormack, D., & Buffenstein, R. (1998).Short-term effects of macronutrient preloads on appetite and energy intake in lean women. Physiology & Behavior, 64(3), 279-285.
  8. Weigle, D.S., Breen, P.A., Matthys, C.C., Callahan, H.S., Meeuws, K.E., Burden, V.R., & Purnell, J.Q. (2005). A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. The American Journal of Clinical Nutrition, 82(1), 41-48.
  9. Westerterp, K.R. (2004). Diet induced thermogenesis. Nutrition & Metabolism, 1, 1-5

The Importance of Zinc

The human body absorbs approximately 400kg zinc over the average 70-year lifespan and at any one time there should be 2-4 gm zinc in the body. It is the second most abundant mineral ion ( Magnesium is the first) in the body and is the only metal that appears in all enzyme classes The body absorbs 20-40% of zinc in food, zinc from animal foods being more readily absorbed (twice as much ) than zinc from plant foods. Zinc is also more readily absorbed with a protein meal and although the body cannot store zinc and it is needed every day in small amounts (50mg or less), it may be held in metallothionine reserves and transferred in metal transporter proteins. Metallothionines in the intestinal cells are capable of adjusting the absorption of zinc by 15-40%. Thus control of cellular zinc homeostasis is maintained by zinc proteins and zinc binding metallothioneines. Zinc is needed for over 300 enzymes in the body and makes up part of 3000 different proteins in the body. Muscles (60%) and bones (30%) contain 90% of the body’s zinc. High concentrations of zinc are found in the prostate gland and semen and the choroid of the eye.

If bone is reabsorbed or muscle is broken down then some zinc can be reutilised and in cases of zinc depletion changes in immune status alter before any decrease in levels of plasma zinc. There is a small exchangeable pool of zinc (100-200mg ) that depends on recently absorbed zinc and the intestinal excretion of zinc. As with Magnesium, the efficiency of absorption of zinc is inversely related to the amount of zinc present in the body. The greater the level of body zinc, the less absorption occurs. Zinc, Magnesium Calcium and Iron all compete for transporters in the intestine for uptake above a threshold of approximately 800mg so consuming these minerals together below this level should not interfere with uptake Zinc is found in all cells in the body and the daily requirement is dependent on age and activity.

Zinc deficiency is due to

  • Soil deficiency.

  • Some drugs deplete zinc.

  • Vegetarian and vegan diets may be deficient.

  • High cereal based diets, containing high phytate foods which can bind with zinc and impair absorption.

  • Cooking with water can result in leaching of up to 50% of zinc levels of the food.

  • Refined processing of wheat and baked goods can result in up to 75% zinc loss

 

Tetracycline and quinolone antibiotics react with zinc in the intestines inhibiting the absorption of both the antibiotic and zinc. The antibiotic should be taken 2 hours or more before or at least 4-6 hours after the zinc supplement to avoid this. 

In short over 300 enzymes are zinc dependent, including enzymes involved in the synthesis of certain proteins such as collagen and wound healing. Also needed for thymic hormone activation and maintaining a normal immune system, testosterone and oestrogen, fertility and reproduction including cell division. It is involved in gene regulation, maintaining acid/base balance in the body and normal carbohydrate, fat and protein metabolism. It is needed for normal bones, skin, hair and nails and normal brain function including maintenance of normal vision. It can also act as an antioxidant, protecting DNA, lipids and proteins in the body.

Zinc Contributes to

Normal DNA synthesis. Although the exact role of zinc in DNA synthesis is not fully understood but it does play a structural role in zinc fingers, which are finger shaped proteins. Due to their shape, these proteins can bind to DNA and RNA allowing them to function in Gene expression. These proteins are the most common transcription factors in living organisms, transcription factors are proteins that bind to DNA and control the transfer of genetic information to RNA Put simply Zinc is needed for reading genetic instructions and lack of zinc may mean that instructions get misread or not read at all.

Normal acid/base metabolism. Acid/Base balance is the balance between acid and alkaline to keep body fluids as close to a neutral pH (pH7) as possible. Carbon dioxide and water are rapidly converted to bicarbonate and water (and back again) to maintain acid base balance in the blood and other tissues. The enzyme responsible for this is the zinc dependent enzyme Carbonic Anhydrase. Studies have shown that dietary deficiency of zinc reduces red blood cell carbonic anhydrase activity

Normal carbohydrate metabolism. Deficiency of zinc results in a drop of metabolic rate. Zinc dependent messenger RNA is needed to synthesise the enzymes required for carbohydrate metabolism so zinc deficiency may result in lack of these enzymes. Zinc may also interact with insulin by controlling the uptake of glucose by adipocytes (fat cells). Zinc deficiency results in impaired carbohydrate metabolism.

Normal cognitive function Zinc is highly concentrated in the cerebral cortex, pineal gland and hippocampus and zinc deficiency is associated with impaired memory formation and mood disorders. In the hippocampus zinc can reach concentrations of 8% of the total brain zinc. Zinc ions are also NDMA (N-methyl-D –aspartate) antagonists (NDMAs control memory function and excessive NDMA activation results in cell death due to excess calcium influx into neuronal cells ) so zinc becomes important for normal neuronal function and memory and delaying brain cell death . Normal fertility and reproduction. Steroid hormones such as testosterone and oestrogen are derived from cholesterol and zinc plays an important role in cholesterol metabolism. Low dietary zinc is associated with low concentrations of several hormones including testosterone.

Testosterone. Circulating testosterone and free testosterone appears to increase with oral zinc intake. In one study supplementing with 250 mg zinc sulphate for 6 weeks increased testosterone by 85% in people on hemodialysis.

Free Testosterone is converted to DHT (dehydrotestosterone) by the enzyme 5alpha-reductase ) primarily in the prostate gland, testes , adrenal glands and hair follicles. DHT is increased in infertile men and as it has an affinity for the hair follicles can result in male pattern baldness. Zinc has been shown to inhibit ( up to 98%)the enzyme 5 alpha reductase.

Semen: Semen is very rich in zinc. Sperm count, motility and physical characteristics of sperm increase and improve with some groups of infertile men.

Zinc deficiency has also been associated with increased expression of oestrogen receptors. The enzyme aromatase converts testosterone to oestrogen and zinc decreases aromatase activity so preventing excessive conversion of testosterone to oestrogen. Zinc deficiency can cause testicular cell death, increase protein oxidation in the testes, dysregulating other enzymes and proteins resulting in degeneration of testicular structures and impaired testosterone secretion.

Why should I Take A Zinc Supplement?

Normal macronutrient metabolism. Macronutrients are carbohydrates, fats and proteins. Zinc is needed for the enzymes that metabolise carbohydrates, fats and proteins

Normal metabolism of fatty acids- zinc is needed for the conversion of linoleic acid to Gamma Linolenic acid (GLA) and for the synthesis of prostaglandins series 1 ( Anti inflammatory prostaglandins) Zinc also plays an essential role in maintaining a balance between to different forms of prostaglandins.

Maintenance of normal serum testosterone concentrations, so involved in fertility and reproduction. Zinc plays a role in cell signalling, influencing hormone release and nerve function.

Normal metabolism of vitamin A. Zinc is necessary to maintain normal concentrations of vitamin A in the plasma, being essential for normal mobilization of Vitamin A from the liver. Zinc deficiency decreases the synthesis of Retinol Binding protein (RBP) in the liver leading to lower levels of RBP in the plasma.It influences the absorption, transport and utilisation of Vitamin A. . Zinc is also required for the enzyme Alcohol dehydrogenase , responsible for converting retinol to retinal, essential for eye function.

Normal protein synthesis. One of the important zinc dependent proteins is Gustin which is involved in taste and smell. Poor or absent gustin levels results in impaired taste and smell. Other important zinc containing enzymes are carboxopeptidase which helps break down protein. Zinc deficiency also impairs the synthesis of the protein Opsin, the precursor of Rhodopsin, which if decreased, results in abnormal dark adaptation of the eye. Zinc is also required for the enzyme alcohol dehydrogenase , responsible for converting retinol to retinal, essential for eye function. Haemoglobin is a protein and zinc s important in haemoglobin synthesis.

Maintenance of normal bones. Zinc regulates the secretion of calcitonin from the thyroid gland and therefore influences bone turnover. Zinc appears to regulate the bone matrix calcification in osteoblasts. Zinc deficiency decreases the activity of matrix proteins, type 1 collagen and alkaline phosphatase decreasing Calcium and Phosphorus accumulation. Therefore zinc deficiency may become a risk factor for poor extra cellular matrix calcification.

Maintenance of normal hair and nails Zinc is needed for building keratin and formation of collagen and for facilitating cell division that makes hair growth possible.

Maintainance of normal skin. Collagen in skin is produced by zinc dependent enzymes , the collagenases. Type 1 collagen is produced in the skin and is a structural long lived protein produced by fibroblasts. Collagen constitutes 70% skin mass and give the skin its structure and resistance to traction and strains. Total collagen decreases 1% a year resulting in decreased elasticity and aging skin. Zinc is essential not only for the enzymes producing collagen but also the cross linking that give collagen its stability. Human studies have shown that decreased zinc resulted in decreased total collagen.

Maintenance of normal vision Zinc supplementation alone significantly reduced the risks of developing AMD in subjects at higher risk. Zinc deficiency also impairs the synthesis of the protein Opsin, the precursor of Rhodopsin, which if decreased, results in abnormal dark adaptation of the eye. Zinc is also required for the enzyme alcohol dehydrogenase , responsible for converting retinol to retinal, essential for eye function.

Contributes to normal function of the immune system. Plays a central role in the immune system affecting cellular and humoral immunity. It is essential for thymic dependent T cells . Zinc deficiency results in decreased levels of all types of white blood cells. It is also required for the production of Thymulin (thymic hormone) Zinc ions also exhibit direct anti microbial activity.

Contributes to protecting the cells from oxidative damage, protecting the DNA, lipids and proteins . Loss of zinc from biological membranes increases their susceptibility to oxidative damage. Zinc is also necessary for the antioxidant enzyme Super Oxide Dismutase (SOD)and low levels of zinc supplementation resulted in increased levels of glutathione peroxidase , SOD and decreased lipid peroxidation.

The process of cell division. Zinc contributes to normal DNA synthesis and cell division. Zinc appears to be essential for Insulin like growth factor (IGF) which induces cell proliferation. Reduced zinc availability appears to affect membrane signalling and secondary messengers that coordinate cell proliferation. Ref : The Role of Zinc in Growth and Cell Proliferation by Ruth MacDonald published In The American Society for Nutritional Sciences Reference

What Are The Symptoms Of A Mild Zinc Deficiency?

  • Loss of appetite.

  • Poor growth.

  • Weight loss.

  • Diminished taste or smell.

  • Poor wound healing.

  • Skin problems, acne, psoriasis atopic dermatitis.

  • Poor vision, night blindness.

  • White spots on finger nails.

  • Depression, apathy.

What Are The Symptoms Of A Severe Zinc Deficiency?

  • Delayed sexual and bone maturation

  • Skin lesions

  • Diarrhoea

  • Loss of appetite

  • Hair loss

  • Increased susceptibility to infections

  • Behavioural changes

The passage of zinc into the body

Studies involving direct comparison of bioavailability of different forms of zinc in humans are few. The important fact is that the form of zinc needs to become dissociated into zinc ions which then bind to ligands ( proteins ) that transport the zinc into the cells of the small intestine. There are specific transport proteins that carry zinc across the cell membrane into the portal circulation where it is transported directly to the liver before being released into the circulation for delivery to all tissues. Approximately 70% of zinc is bound to serum albumin ( a plasma protein ) and factors altering serum albumin in turn affect serum zinc levels. Serum zinc has a rapid turnover to meet tissue demands.

Zinc is lost through the skin and kidneys (combined loss of 0.5-0.8mg/day) , more zinc being lost when the body sweats more, as in hot climates and during strenuous exercise. Approximately half of all zinc eliminated from the body is lost through the shedding of epithelial cells in the gastro intestinal tract (0.5- 3mg/day) and although a considerable amount is secreted through both biliary and intestinal secretions, most of the secretions are reabsorbed regulating the zinc balance. Starvation and muscle breakdown also increase zinc loss through the urine.

As already mentioned, protein enhances the absorption of zinc and a phytate rich diet (from cereals, grains, corn and rice) inhibit the absorption of zinc.

There is a very fine balance between zinc and copper. Zinc reduces the amount of copper your body absorbs because copper competes with zinc to bind with metallothionein, the binding protein that brings zinc into the intestinal cells. The ratio of zinc : copper is arguably more important than the concentration of either copper or zinc, a common problem being excessive copper in water from copper pipes or copper cookware.

Zinc also competes with iron to bind with blood transferring, illustrating the importance of a balance of these minerals. The ECRDA for zinc is 10 mg less is required for babies, children and teenagers and more for pregnant and breastfeeding ladies.

Recommended Daily Allowance For Zinc Supplements

Bioavailability Of Different Forms Of Zinc Supplements

There are many forms of zinc compounds. 

  • Zinc Picolinate 20%

  • Zinc Ascorbate 15%

  • Zinc Chloride 48%

  • Zinc Sulphate 22%

  • Zinc Carbonate 52%

  • Zinc Citrate 31%

  • Zinc Bisglycinate 25%

There is not much substantial evidence of greater effectivity of one form of zinc over another as absorption of zinc in the body is subject to so many variables.

However, a small research study (15 healthy young adults in a randomised, double blind three way cross over study, receiving 10mg of elemental zinc as a supplement without food just published (20 November 2013) found that the bioavailability of zinc citrate was 61.3% , of zinc gluconate was 60.9% and of zinc oxide was 49.9 % Previous zinc intake may affect zinc bioavailability studies. Variables include;

  • Existing zinc status of the individual. The lower the zinc status of the individual, the greater the absorption of zinc.

  • People that sweat a lot are subject to more zinc loss, for example athletes, those in hot climate, menopausal ladies experiencing night sweats.

  • Dosage of zinc- as zinc intake in dosages is increased , percentage absorption decreases probably due to the saturation of the transport mechanisms.

  • Zinc absorption appears to be decreased in the elderly.

  • Zinc absorption is increased with dietary protein intake.

  • The type of protein in a meal affects zinc bioavailability. Animal protein enhances absorption.

  • Phytates in cereals and soy inhibit absorption of zinc by binding with it ( except zinc bisglycinate found in Metabolics zinc formula).

  • Caesin in milk and calcium inhibit absorption by binding with zinc ions.

  • Iron inhibits absorption of zinc.

  • Copper ( in high amounts ) inhibits Zinc absorption. In studies using 15mg zinc combined with 2mg copper no inhibition of absorption was found.

  • Cadmium- toxic levels of cadmium can inhibit zinc absorption

Conclusion

Types of zinc supplements may remain a personal preference, although generally zinc should not be taken on an empty stomach (as it can result in nausea) should be taken with an animal protein meal , away from cereals and taken in conservative doses to increase absorption. Long term zinc intake is recommended with copper (see zinc formula) as this is zinc bisglycinate, the only form not affected by phytates and balanced with a small amount of copper.

 

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Understanding Methylation

Methylation is a key biochemical process that is essential for the proper function of almost all of your body’s systems. It occurs billions of times every second; it helps repair your DNA on a daily basis; it controls homocysteine (an unhealthy compound that can damage blood vessels); it helps recycle molecules needed for detoxification; and it helps maintain mood and keep inflammation in check.

To keep methylation running smoothly you need optimal levels of B vitamins. Without enough B vitamins methylation breaks down, and the results can be catastrophic. In these cases we see more birth defects like spina bifida, more cases of Down’s syndrome, and more miscarriage.

A breakdown in methylation also puts you at higher risk for conditions like osteoporosis, diabetes, cervical dysplasia and cancer, colon cancer, lung cancer, depression, pediatric cognitive dysfunction ( mood and other behavioral disorders), dementia, stroke and may put you at a higher risk of heart disease.

To avoid all of these problems, the key is to maximize methylation. That means avoiding the things that cause your methylation to break down, testing to find out how well your methylation is working, and including the things that support proper methylation. Let’s look at how to do that.

8 Factors that Affect Your Methylation Process

  1. Genetics – Like an estimated 20 percent of us, you could be genetically predisposed to high homocysteine
  2. Poor diet – The word “folate” comes from “foliage.” You need to eat plenty of leafy greens, beans, fruit, and whole grains to get adequate levels of vitamins B6 and B12, betaine, and folate. Egg yolks, meat, liver, and oily fish are the main dietary sources of vitamin B12 — so long-term vegan diets can be a problem. Plus, certain compounds can raise levels of homocysteine and deplete the B vitamins. These include excess animal protein, sugar, saturated fat, coffee, and alcohol. Irradiation of food depletes nutrients, so foods treated this way may be lower in B vitamins, too
  3. Smoking – The carbon monoxide from cigarette smoke inactivates vitamin B6
  4. Malabsorption – Conditions like digestive diseases, food allergies, and even aging can reduce absorption of nutrients
  5. Decreased stomach acid – Aging and other conditions can reduce stomach acid — and therefore absorption of vitamin B12
  6. Medications – Drugs like acid blockers, methotrexate (for cancer and arthritis and other autoimmune diseases), oral contraceptives, HCTZ (for high blood pressure), and Dilantin (for seizures) can all affect levels of B vitamins
  7. Other conditions – These include hypothyroidism, kidney failure or having only one kidney, cancer, and pregnancy
  8. Toxic exposures – Some toxins can interfere with vitamin production

Watch out for these factors and you will go a long way toward protecting your methylation.

Measuring Your Own Methylation Process

To find out if your methylation process is optimal, ask your doctor for the following tests:

  • Complete blood count – Large red blood cells or anemia can be a sign of poor methylation. Red blood cells with a mean corpuscular volume (MCV) greater than 95 can signal a methylation problem
  • Homocysteine – This is one of the most important tests you can ask for. The normal level is less than 13, but the ideal level is likely between 6 and 8
  • Serum or urinary methylmalonic acid – This is a more specific test for vitamin B12 insufficiency. Your levels may be elevated even if you have a normal serum vitamin B12 or homocysteine level
  • Specific urinary amino acids – These can be used to look for unusual metabolism disorders involving vitamins B6 or B12 or folate, which may not show up just by checking methylmalonic acid or homocysteine

12 Tips to Optimize Your Methylation Process

Just as there are many causes of poor methylation, there are lots of things that support its proper functioning. Here’s how to maximize methylation — and prevent conditions like heart disease, cancer, dementia, depression, and more.

  1. Eat more dark, leafy greens – You want to eat l cup a day of vegetables like bok choy, escarole, Swiss chard, kale, watercress, spinach, or dandelion, mustard, collard, or beet greens. These are among the most abundant sources of the nutrients needed for optimal methylation
  2. Get more Bs in your diet – Good food sources include sunflower seeds and wheat germ (vitamin B6); fish and eggs (vitamin B6 and B12); cheese (B12); beans and walnuts (vitamin B6 and folate); leafy dark green vegetables; asparagus, almonds, and whole grains (folate); and liver (all three)
  3. Minimize poor quality animal protein, sugar, and saturated fat – Animal protein directly increases homocysteine. Sugar and saturated fat deplete your body’s vitamin stores
  4. Avoid processed foods and canned foods – These are depleted in vitamins
  5. Avoid caffeine – Excess amounts can deplete your B vitamin levels
  6. Limit alcohol to 3 drinks a week – More than this can deplete your B vitamin levels
  7. Don’t smoke – As noted above, smoking inactivates vitamin B6
  8. Avoid medications that interfere with methylation – See notes on this above
  9. Keep the bacteria in your gut healthy – Take probiotic supplements and use other measures to make sure the bacteria in your gut are healthy so you can properly absorb the vitamins you do get
  10. Improve stomach acid – Use herbal digestives (bitters) or taking supplemental HCl
  11. Take supplements that prevent damage from homocysteine –Antioxidants protect you from homocysteine damage. Also make sure you support methylation with supplements like magnesium and zinc
  12. Supplement to help support proper homocysteine metabolism – Talk to your doctor to determine the best doses and forms for you.  Here are a few suggestions:
    Folate (folic acid): Amounts can vary based on individual needs from 200 mcg to 1 mg. Some people may also need to take preformed folate (folinic acid or 5 formylTHF) to bypass some of the steps in activating folic acid
    Vitamin B6: Take 2 to 5 mg a day. Some people may need up to 250 mg or even special “active” B6 (pyridoxyl-5-phosphate) to achieve the greatest effect. Doses higher than 500 mg may cause nerve injury
    Vitamin B12: Doses of 500 mcg may be needed to protect against heart disease. Oral vitamin B12 isn’t well absorbed; you may need up to 1 or 2 mg daily. Ask your doctor about B12 shots
    Betaine: This amino acid derivative is needed in doses from 500 to 3,000 mg a day, depending on the person

Understanding Cholesterol

Cholesterol is one of the least understood molecules and truly gets a "bad rap." Although people understand that cholesterol is only present in animal-based foods, what many do not know is that we produce cholesterol just like any other animal, and it is a very necessary molecule used to form all of the cell membranes in the body. Cholesterol is also the building-block molecule from which all of the steroid hormones are made. If there is more cholesterol in the diet than is needed, then the body synthesizes less. If the diet does not provide enough cholesterol then the body makes more.

Since cholesterol is used by the body to manufacture hormones such as cortisol, we can look at what cortisol is and make some logical connections. Cortisol is widely regarded as a "stress hormone" since the body needs and produces more of it in response to stress. This stress response takes many forms; one of them is lowering inflammation--useful if your version of stress involves hand-to-hand combat with large carnivores or fighting for your life. The lowering of inflammation is why the pharmaceutical versions of cortisol (Hydrocortizone and other glucocorticoids) are used to reduce inflammation in cases of massive trauma or major surgery. Other effects of cortisol are the elevation of blood pressure, release of glucose from the liver, inhibition of the immune system, retaining of water/reducing kidney function (probably useful if the combat with the large carnivores leads to bleeding form flesh wounds, as retaining water would help to maintain blood volume when bleeding profusely) and other effects. Taken together, when stress levels remain high, lots of cortisol is produced. It would then make sense that making a lot of cortisol requires a lot of what is made from, which is cholesterol. Therefor, during periods of high stress (a lifetime for many people), the levels of cholesterol can become very elevated. When the stress is long-term, the stress will end up raising the inflammation level through other mechanisms; effectively, stress reduces inflammation in the short-term only. Cholesterol has many other uses in the body, including the formation of myelin--the insulating/speeding sheath that wraps around the nerves, like rubber coating surrounding a copper wire, that increases their conduction velocity (and is damaged in multiple sclerosis).

Dietary modifications to reduce cholesterol has been met with mixed results. Some people can follow a strict no-cholesterol diet and achieve a lowering of their plasma cholesterol levels, while other are not able to accomplish this. This failure of dietary regimen to achieve the desired goal may be because of the body's production of cholesterol to meet the necessary levels for the amount of stress the individual is experiencing. The failure may also be because of reduced utilization of cholesterol. The gut bacteria play a role here also with Lactobacillus bacteria actively consuming cholesterol. Lactobacillus not only consumes cholesterol, but it makes bile acids that aid in the digestion of fats out of the cholesterol that it consumes. It therefore makes sense that if a person has altered gut bacteria demographies and Lactobacillus are in the minority, that person will not use up as much cholesterol and the cholesterol levels may accumulate. Elevated levels of stress reduce the levels of Lactobacillus, providing the pathway for stress to reduce the beneficial effects of a healthy diet. The same imbalance may also predispose the person to inflammation, which is the real cause of heart disease.

The use of probiotics in dairy products to control cholesterol greatly predates modern science, as the Maasai tribe in Kenya use a probiotic fermented milk in their diet. The Maasai diet is composed almost entirely of meat, milk and blood. This diet includes several times the recommended level of cholesterol, and yet the Maasai have no problems with atherosclerosis or other degenerative diseases that could be related to their diet. What has been found is that their fermented milk (no refrigeration, so it all gets fermented if not immediately consumed!) contains probiotic bacterial population s that help to consume and lower cholesterol. Other sources of probiotics, such as yogurt, have been found to lower cholesterol levels also. 

Many people incorporate yogurt into their diet because they like it or they think that it is healthy--but what makes it healthy? Much of the yogurt on store shelves has no bacterial colony whatsoever, so it is important to read the ingredients! If it has no "live active cultures," then it has little if any health benefit to our good bacteria and subsequent immune function.

Eggs have often been the poster child of high cholesterol food, if the yolk is used. However, consuming eggs may not have as much to do with elevated cholesterol level as initially thought. Similarly, fats were implicated in the disease process, as it has been observed that people with high triglycerides (fats) in their blood are at increased risk of developing heart disease. There are other variables in this equation, as is often the case. For example, abnormal populations of gut bacteria promote atherosclerosis by causing inflammatory changes and altered metabolism of lipids. The presence of abnormal gut bacteria that cause irritable bowel syndrome is directly linked to the development of thickening of the wall of arteries, which is of course the actual structural change that is at the center of what we call atherosclerosis.

Excerpt from The Symboint Factor by Richard Matthews DC DACNB FACFN

Avoid the Worst Ingredients

Flavor enhancers, preservatives, sweeteners, synthetic colors and manmade fats and chemicals commonly hide out in the ultra-processed foods we eat. If you want to stay away from putting harmful chemicals on your table, it’s necessary to learn how to identify the worst ingredients and find healthier alternatives. Let’s take a look at how to get started.

1. Identify and avoid these seriously dangerous additives

It’s not easy to remember all of the worst ingredients to steer clear of, but learning to avoid the most toxic ones commonly found in the food supply can drastically improve your health. A common food additive is monosodium glutamate (MSG) that is very dangerous and affects human body in a variety of ways. Headache, nausea, vomiting, pain in the back of the neck, numbness and heart palpitations are common side-effects of consuming MSG. Monosodium glutamate is an excitotoxin that overexcites the cells in your body to the extent where they are so heavily damaged that they die. MSG also leads to a range of neurological diseases on prolonged exposure. (12)

It’s not easy to find processed foods that are completely free of MSG. Other food ingredients often mask the presence of MSG, including:

  • autolyzed yeast
  • hydrolyzed protein
  • hydrolyzed vegetable protein
  • sodium caseinate
  • yeast nutrient or yeast extract
  • Torulo yeast
  • natural flavoring
  • glutamic acid

Soy sauce, seasonings, powdered milk, stock, malt, maltodextrin, pectin and anything protein often contain MSG.

2. Avoid the toxic heart attack ingredient

Trans fats are very harmful. These artificial trans fatty acids lower the level of good cholesterol (HDL) and increase the level of bad cholesterol (LDL) in your body. Primarily used in processed foods, trans fats are formed when food manufacturers add hydrogen to liquid oil to solidify it. (They do this to increase shelf life.) Unfortunately, trans fats have been blamed for up to 50,000 premature heart attack deaths a year. (3)

In the hydrogenation process, oil is heated to an extremely high temperature of about 500 to 1000 degree Celsius. Hydrogenated oil is a fabulous preservative because all the natural enzymes are destroyed by the high heat, rendering the end product as an unhealthy sludge. If you see terms like hydrogenated oil, partially hydrogenated oil or fractionated oil on food label, do not buy the products.

3. Steer clear of metabolism-sinking sweeteners

Artificial sweeteners may seem like a good choice if you’re watching your calories, but science shows us it’s really one of the worst ingredients when it comes to your metabolic health. High-fructose corn syrup (HFCS) is a sweetener that leads to weight gain, heart complications and obesity.

Some artificial sweeteners result in headaches and mood swings as well. Aspartame, saccharin and sucralose are widely used artificial sweeteners and can exert a bigger load on your metabolic system than plain old sugar. They also trick your brain into feeling less full, prompting you to eat more, which in turn can lead to weight gain. So monitor your intake of artificial sweeteners to stay fit.

4. Beware of these 3-letter cancer causers

Butylated hydroxyanisole (BHA) and Butylated hydroxytoluene (BHT) are processed food preservatives that have been found to have carcinogenic properties by the International Agency for Research on Cancer. BHA has been declared safe by FDA, but it is termed ‘reasonably anticipated to be a human carcinogen’ by U.S. Department of Health and Human Services. (45)

BHA has been shown to act as an endocrine disruptors, interfering with healthy hormone production, too. (6) BHA and BHT preservatives are commonly found in cereals, potato chips, chewing gum and cereal snack mixes. (Read your cosmetics labels, too. They often hide out in personal care products.)

5. Don’t assume soy is safer

Is soy bad for you? In the majority of cases, particularly as it pertains to soy as an ingredient in processed foods, it is unhealthy. While many of us think that soy and soy products as healthy and protein-rich, this is not always true. A majority of soy used in processed food products is genetically engineered. That means the crop has been tinkered with on a genetic level to receive applications of glyphosate, the main ingredient in Roundup weedkiller, without killing the plant. This has led to “excessive” levels of glyphosate turning up in the food we eat. (7) In 2015, the World Health Organization declared glyphosate “probably carcinogen to humans.” That makes conventional soy one of the worst ingredients.

Consuming GMO ingredients in considerable quantity over a long period of time is suspected to lead to infertility, gluten disorders, allergies and even cancer. Though the jury is still out on this controversial topic, with several studies showing that GMO ingredients are safe, I suggest practicing the precautionary principle, meaning it’s always best to consume processed foods that rely the least on GMO ingredients, staying as natural as possible. (8)

Pre Workout Supplements: Hypertrophy Priority

Here are some supplement recommendations for athletes seeking to maximize Hypertrophy. With Hypertrophy we are trying to maximize the acidic environment to induce as much damage, cell swelling and hyperemia as possible. What can we take preworkout to help this along?

Primarily, we will want to look at things that shuttle nutrients and blood into the muscle. 

  1. Citruline Malate: reduces fatigue and improves muscle endurance. More effective than Arginine. Arginine actually decreases GH during your workout when taken pre exercise. Arginine is best used before bed. 
  2. Antioxidants : Alpha Lipoic Acid, grape seed extract and CoQ10 improve mitochondrial function and will allow for more blood flow to muscles during training.
  3. Beet Root Powder: Vasodilator, will induce a pretty gnarly pump.
  4. Neurotransmitter boosters: these will be important for anyone that has a hard time getting amped up to train. I advise against taking caffeine as a pre workout before Hypertrophy sessions because caffeine is a vaso constrictor. That means that taking caffeine with nutrients to chase the pump is a bit futile. There is a trade off for sure. If training without caffeine leads to a shit workout, then it may be worth your while to take caffeine instead of some of the vasodilators. Taking both at the same time though, to me, is a waste of money.
  5. BCAAs: provides energy and will prevent muscle protein breakdown during training.
  6. Creatine: will help sustain energy levels throughout your sessions and get more fluid into the muscles.
 
 

Chocolate Milk For Post-Workout: A Look at the Research

Over recent years, there has been a massive initiative to promote chocolate milk as “the best” drink for post-training recovery. Milk advertisers use very high level athletes as spokespersons to sell a product to people who are indeed active, but often very far from the training level of an Olympic athlete.

Nautilus Plus is participating to this initiative: “Whether you are a professional athlete or a weekend sports enthusiast, recover from your next training faster with the Ultimate Chocolate Milk®.”(1) Do we really need to fill ourselves with all this added sugar after our training?

One litre of chocolate milk contains up to 100 to 110 g of sugar!!! The quantity of sugar that the body can absorb is limited. In fact, the sugar will be stored in the liver and muscles in the form of glycogen, which only represents 5 % of the body’s total energy reserves (2). If your objective is, as for the majority of people, to lose fat, you need to remember this: to allow yourself to consume a supplement rich in carbohydrates after your training, you will have to have emptied or seriously depleted your glycogen stores in order for the extra sugar absorbed to be used to renew your glycogen stores. And if you absorb more sugar than you need to renew your reserves, it will be transformed into fat (3).

Scientific studies

Many scientific studies have been done on sports nutrition supplements and some included chocolate milk. The purpose of these studies was to determine which mixture of molecules, and in what proportion, best promotes post-training recovery as well as athletic performance. Almost all these studies followed this particular protocol:

  1.  Study participants were subjected to intense exercise at 70 to 85% of their VO2 max during 1 to 3 hours. The purpose of this step was to considerably reduce the muscle and hepatic glycogen stores since 70 to 80% of the energy spent at 85% VO2 max is derived from glycogen. Under 65% of VO2 max, mostly fatty acids are used (4, 5).
  2. A recovery period between 4 and 8 hours followed to allow the participants to replenish their glycogen stores with the various sports nutrition supplements covered in the study.
  3. Participants were then subjected to a second high intensity exercise (VO2 max between 70 and 85%) until exhaustion (loss of 85 to 95% of their hepatic glycogen and 65 to 85 % of their muscle glycogen) (6). The difference in time or distance between the performances will determine which sports nutrition supplements helped the athlete the most to recuperate between the two sessions.
    .

The role of these sports nutrition supplements is therefore to replenish as quickly and efficiently as possible the glycogen stores which were SIGNIFICANTLY depleted during the first training, in order to allow a second intense performance within 4 to 8 hours.

This situation is certainly frequent among Olympic athletes or athletes from the Tour de France who train several times per day or several days in a row at extreme intensities, but what about other people? Is chocolate milk a good supplement for “weekend athletes” or people who train leisurely, three of four times per week?

After your leisure strength training?

For a person who does resistance strength training, the glycogen stores will fall by 25 to 40 % after an intense strength training (7 to 12), which is relatively little. The glycogen stores lost during the training will be rebuilt through normal nutrition, WITHOUT ANY SUPPLEMENTS, within 24 hours of the training. However, some people consider it very important to MAXIMIZE the production of lean muscle mass. So the rapid intake of PROTEIN supplements after the training (within 1 hour if possible, up to 3 hours later) is important since it promotes maximum muscle synthesis(13 to 33). Recently, a research team questioned this principle claiming that it would be the total quantity of proteins ingested each day that would prevail over the moment at which they are ingested (34, 35). The same team also mentioned that if a “window” for taking a protein supplement and maximizing the production of lean muscle mass does exist, it would rather span over a 4 to 6 hour period following the strength training.

According to various recent studies, 20 to 25g of proteins would be the recommended amount to take after a resistance training (25, 33, 36). Witard et al., 2014 consider that 20 g of whey protein containing approximately 2 g of leucine optimally stimulates muscle synthesis (33). A litre of chocolate milk contains approximately 30g of proteins, including 80% of micellar casein and 20% of whey (37). Studies on post-training muscle synthesis clearly show the very poor efficiency of micellar casein for this purpose (26, 28, 38, 39, 40) because it precipitates in the stomach and the absorption of amino acids responsible for muscle synthesis is therefore very slow (26, 41, 42, 43). One argument that is often used by chocolate milk advocates is that milk (skim) is more efficient than soy protein or casein to promote muscle synthesis (23, 24). That’s true! It is actually the 20% of whey proteins contained in the milk that makes it efficient for muscle regeneration (26, 28, 40). What they don’t say is that purified whey protein (concentrate or isolate) is the best all around for lean muscle mass gain (26, 28, 40, 44, 45, 37) and, consequently, is better than milk. Whey protein is very rich in BCAA and is quickly absorbed by the intestine, as opposed to casein which is absorbed slowly. Therefore, why take a milk supplement if a whey protein shake is more efficient? Not only does chocolate milk contain large quantities of casein, but it can also contain saturated fat (if it’s full fat) as well as a large quantity of added simple sugars, on top of the lactose. So, is it useful to add all this sugar to the proteins (which are already not optimal) to maximize muscle synthesis after my resistance training?

Some studies show that carbohydrates (CHO) could inhibit muscle breakdown caused by training (10, 46, 47, 48, 49). A few groups claim that a carbohydrate/protein (CHO:PRO) supplement would facilitate a better muscle synthesis since it would inhibit muscle breakdown (15, 32, 46, 48, 50, 51). Nevertheless, some of these studies did not include a control group for the proteins (PRO) only. So it is difficult to evaluate whether adding CHO to PRO provides an advantage or not over PRO taken separately. As for the few studies that included a control group for the PRO, the quantity used was sub-optimal and was given in the form of amino acids (46, 48, 50). However, when a control group taking PRO optimally is included in the study, adding CHO to PRO did not show any advantage in terms of lean muscle mass gain (49, 52 to 57). CHO: PRO ratios used in the studies on resistance training varied between 1:1 and 3:1 whereas chocolate milk offers a ratio between 3:1 and 4:1. That is a lot of unnecessary sugar!

In turn, adding CHO to protein supplements can be necessary when several INTENSIVE resistance trainings are planned during the same day. In such a case, the athlete must quickly renew its glycogen stores (58, 59). To this end, 1g/kg of weight of CHO should be added to the proteins and consumed immediately after the training; moreover, a meal should follow 2 hours after the training (59, 60)So you must weigh at least 220 lbs and must train intensely more than once a day to allow yourself a litre of chocolate milk. Even then, you won’t achieve optimal results because of the casein, which constitutes 80% of the total proteins, and because of the 2:1:0.46 (glucose:fructose:galactose) ratio of the various sugars present in the chocolate milk (61).

The fructose contained in chocolate milk comes from high fructose corn syrup (which has a very bad reputation) and from sucrose (1 glucose +1 fructose). In 2004, Bray GA et al. suggested that the obesity epidemic in the United-States was related to the HFCS found everywhere and in large quantities in our nutrition (62). However, the new report published by The International Journal of Obesity, 2015 (63) suggests that this epidemic cannot be linked to HFCS due to the lack of evidence demonstrating that HFCS would be worse than table sugar (sucrose) (63, 64, 65). Yet, chocolate milk contains both of these additives. The fructose contained in almost equal quantities in both these additives could be linked to obesity (66, 67). Some scientists are reluctant to establish such a link (63, 64)A small quantity of fructose consumed every day, such as normal consumption of fruits, is harmless. Unfortunately, fructose is now added in almost all processed food. So it’s easy to exceed the healthy daily quantities of “natural” fructose. The body metabolises fructose differently from glucose. The liver metabolises 70% of the blood fructose (compared to 15 to 30% for the glucose) (38) and will leave the remaining 30% to the other tissues, namely the kidneys, the testicles, the fatty tissues, the brain and the skeletal muscle (69). So the muscles will absorb a negligible amount of fructose (68). A large consumption of fructose can contribute to the development of the metabolic syndrome, consisting in weight gain, increased resistance to insulin, hypertension, and elevated triglyceride in the blood stream (67, 69). High quantities of fructose are also associated to increased cholesterol, LDL particles and visceral obesity (69).

After an intense cardiovascular training, such as a marathon, when the glycogen stores in the liver are low, the fructose present in a sports nutrition supplement will be used to replenish the hepatic stores. Furthermore, for marathon runners performing at high intensities for a long period of time, the intake of fructose in the form of supplements DURING performance at a ratio of 2:1 (glucose/maltodextrin:fructose), offers a definite advantage because it allows faster absorption of sugars through the intestines since different transporters are used for these two sugars. The supplement would also improve gastro-intestinal comfort and would increase these athletes’ performance (70 to 76)If, however, the quantity of fructose consumed is higher than what is needed to replenish the hepatic stores, the surplus could potentially be converted into fat (66). So for people who do resistance training, consuming fructose is of no value. Conclusion? If you need CHO to perform well during your second strength training, you should add glucose/maltodextrin to your whey proteins, in order to avoid consuming fructose unnecessarily.

Finally, at the beginning of 2015, Stuart M. Phillips’ team established that drinking 500ml of chocolate milk every day (18g of proteins) as a supplement, while following a resistance program three times per week over a period of twelve weeks, has no effect on muscle hypertrophy or on strength gain compared to a control group taking no supplements (77).

What about after leisure endurance training?

Many active people do endurance training several times per week such as jogging, spinning, swimming, etc. for one hour. The extent of the muscle and hepatic glycogen loss will vary according to the effort expended. To consume glycogen as a primary source of energy, the level of effort intensity must reach 70% and must be maintained for an extended period of time (4, 5, 78). Laboratory experiments have shown that glycogen stores decline by 50 to 75% after 3 hours of cycling at 70% of VO2max (79, 80). By increasing the effort to 80% of VO2max, you can continue your activity for 2 hours before running out of glycogen. Another example is that the glycogen stores depletion of marathon runners occurs, for 40% of them, around the 34th kilometre, commonly called “the wall”, when they sustain an effort of approximately 80% of VO2max(81, 82, 83) during more than 2h30. Do you think you will be burning as much glycogen during your hour of spinning?

The glycogen stores lost during the training, even if this loss is significant, will be rebuilt through normal nutrition, WITHOUT ANY SUPPLEMENTS, within 24 hours of the training  (84,85). Moreover, the meal frequency will have no incidence if the post-exercise recovery happens over more than 24 hours (85, 86, 87). It is unnecessary for someone coming out of an hour of spinning or jogging to ingest all the added sugars contained in chocolate milk since the subsequent meals will contain sufficient carbohydrates (CHO) to replenish the poorly depleted glycogen stores. Therefore, the person will be ready for the next training a few days later.

Without being Olympic athletes, some people will train intensely and frequently during a week. In such case, the quantity of CHO these people consume every day must be adjusted, spread throughout their meals according to the frequency and intensity of their training. Burke et al. 2011 recommend to take a quantity of CHO every day, depending on the type of training performed (intensity and duration) to allow for a good glycogen resynthesis during the 24 hours following the training (88).

If the objectives of the person doing endurance training don’t include maximum muscular development, the muscle regeneration following an effort, namely the replenishment of glycogen stores, will occur normally with the proteins contained in the subsequent meal, when taken in sufficient quantity.

Supplements are necessary when training sessions are very intense and close together (a few hours) and require to quickly replenish the glycogen stores (in less than 24 hours).

What about high level athletes? (1.3% of the American population are athletes and of which 0.006% are professional athletes) (89).

Although chocolate milk is not intended for Olympic athletes, choosing such athletes as spokesperson to promote chocolate milk as a post-training supplement is almost an obligation; indeed, practically only these athletes could ultimately use chocolate milk as a sports nutrition supplement. Moreover, most studies carried out on the subject are done in a top level training context. But is chocolate milk, as alleged by the television commercials, a good choice for this 1% of the population ?

The purpose of a supplement is to promote fast recovery between two trainings done very close together, mainly by QUICKLY regenerating the glycogen stores. So the muscle glycogen resynthesis speed is important. It was established that this synthesis is faster when CHO are taken right after the training (90, 91, 92) and can be maintained during 6 hours with frequent intake of this supplement (69, 90, 93). Delaying the intake of CHO by 2 hours decreases the resynthesis speed by 50% (16,90). This is particularly important for a fast recovery but is unnecessary for recovery over 24 hours or more (87). OPTIMALLY, the quantity of CHO should be 1.0 to 1.2g/kg of weight/h (94, 95, 96), consumed at 15 to 30 min intervals (97). At this volume and frequency, CHO alone are sufficient to ensure an optimal glycogen synthesis. Sure! But chocolate milk doesn’t only contain CHO!

Is it useful to add proteins to CHO? (98)

To determine which supplement is the best one, we need to compare the different supplements. It is difficult to compare the studies that analyze the effect of adding proteins to a CHO supplement because several variables differ: 1) intensity (% of VO2max) and duration of the first exercise that aims at reducing the glycogen stores 2) choice of exercise (jogging or cycling) 3) various types of supplements consumed (isocaloric or not, as well as the chosen sugars and proteins) 4) control groups used (lack of placebo or other control groups) 5) carbohydrates:protein ratios (CHO:PRO) will vary between 2:1 (Berardi et al. 2006/2008) (99, 100) and 6.2:1 (Betts et al. 2005) (101) 6) duration and intensity of the second performance (% of VO2max).

Nonetheless, it’s possible to draw certain conclusions.

1: Importantly, the drinks studied must be isocaloric (must contain the same amount of calories) :

Some studies show a performance improvement post-recovery when proteins (PRO) are added to CHO versus a control group taking only CHO (102 to 105). However, the quantity of calories between the two drinks was not adjusted, so it wasn’t possible to determine if the performance improvement could be attributed to the addition of proteins or to the aaddition of energy.

2: It is important to compare the CHO+PRO supplement to a control group taking CHO optimally (1.0 to 1.2g/kg of weight/h) AND which is isocaloric:

Some studies show that the addition of proteins to the CHO supplement improves the second performance when compared to a control group taking a CHO only supplement. But this supplement was given sub-optimally during recovery (96, 102, 104, 106, 107). When the control group took the CHO supplement OPTIMALLY, the studies did not show any improvement in the second performance when proteins were added to the mix, even with variable ratios. (95, 96, 101 to 115, 116). A study showed, however, an advantage (100) (see the “Ratio” section).

So the athlete can chose between taking a mix of CHO + PRO, when it is impossible to optimally take a CHO supplement during recovery (1.2g/kg/h every 30 min during 3 to 4 hours) (94, 95, 96, 117). This indeed makes for a lot of CHO to ingest. But at which ratio must the athlete take its proteins?

3: Ratio

Advocates of chocolate milk allege that a ratio of 4:1 is best to support athletic recovery. This belief comes from one of the early studies done on the subject and which showed that a sports nutrition supplement, Endurox R4, containing 4:1 CHO: PRO offered a performance advantage when compared to a control group taking CHO, namely Gatorade (102). However, Endurox R4 contained two and a half times more CHO than Gatorade, in addition to the whey proteins, which gave it almost four times more calories than the Gatorade supplement consumed SUB-OPTIMALLY by the participants. It is obvious that in these conditions, Endurox R4 improved performance compared to Gatorade given the significant difference in CHO and energy consumed between the two drinks. Since the ratio used in this study was 4:1, which is the same as the chocolate milk ratio, the dairy industry took the opportunity to pretend it was the best ratio. Nonetheless, research continued and more recent studies show that ratios containing less sugar are as efficient, if not more, than a 4:1 ratio. Berardi et al. 2008 show an advantage on the second performance with the CHO: PRO mix at a ratio of 2:1 (CHO: 0.8kg/kg/hand PRO: 0.4kg/kg/h), over the control group taking the CHO supplement optimally (100, 117). So why add more sugar than necessary with a ratio of 4:1 if it offers no advantage?

 

Studies done on chocolate milk (McLellan TM et al. 2014 (98)) :

There are 5 major studies comparing chocolate milk to a few other sports drinks during a short term recovery between two performances. (118, 119, 120, 121, 122)

  • None of these 5 studies explained how the chocolate milk taste was reproduced for the control groups. If the athletes know which type of supplement they are given, it can certainly influence the results; in such a case, the study is no longer “blind”.
  • Some studies did not include a placebo or a sub-optimal CHO supplement for the control group (118, 122).
  • 4 studies on 5 did not administer the supplement optimally (118, 119, 120, 121). The fifth study did so for the first recovery hour only (122).
  • Pritchett et al. 2009 show that chocolate milk (3.8:1) offers no advantage for the second performance over Endurox R4 (3.8:1, isocaloric and same quantity of CHO) (118).
  • The other four studies indicated that chocolate milk presented an advantage for the second performance compared to the other drinks studied (119, 120, 121, 122). On the other hand, the studies also present other shortfalls:

For Karp et al. 2006 and Thomas et al. 2009, the glycogen stores reduction protocol was not standardized during the first training(119, 120). That means that the energy expenditure varies a lot from one person to another, even for each individual, from one training session to another. So some groups used more glycogen than others before starting the recovery phase. For Karp et al. 2006 for example, (similar to Thomas et al. 2009), the chocolate milk group (60.8 min) had trained 16% less than the CHO + PRO control group taking Endurox R4 (72.6 min), but equally to the Gatorade group (sub-optimal). These differences can explain the superior performance of the chocolate milk group during the second training. Furthermore, we must report that the study by Karp et al. 2006 was partly financed by the Dairy and Nutrition Council Inc (119).

In the study by Lunn et al. 2012, chocolate milk is compared to a control group taking CHO optimally during the first hour of recovery (122). Despite the fact that the regeneration of the glycogen stores was equal between the two groups, the performance of the chocolate milk group was superior to that of the CHO control group during the second performance (difference of a few seconds). However, the intensity of the second performance was at 100% VO2max and lasted a very short time (203 vs 250 sec). In these very high intensity and very short duration conditions, the more or less important level of muscle glycogen stores before the effort don’t seem to influence performance (123, 124, 125, 126), as opposed to a lower intensity and longer duration performance. So optimally replenishing the glycogen stores is probably not that important in this case. Even the authors admit that the type of test used and the inability to mask the taste of the chocolate milk may have influenced the results. The authors challenge this by emphasizing that the purpose of their study was to show that chocolate milk promotes a better muscle synthesis compared to CHO alone (122). Milk contains proteins whereas the CHO of the control group contained none. So it is not surprising that the results show that chocolate milk increases muscle synthesis. A control group also taking proteins would have certainly given results similar to the chocolate milk, and possibly even better results if whey protein would have been used.

 The study by Furguson-Stegall et al. 2011 compared a chocolate milk ratio smaller than 3:1 to an isocaloric CHO drink and to a placebo (water) (121). The drinks were given sub-optimally. The performance of the chocolate milk group was superior by a few minutes during the second training (40km of cycling) compared to the CHO control group. Nonetheless, the glycogen resynthesis was better with the CHO control group, a result that is slightly contradictory. This study was financed by a Chair established by The National Dairy Council, as well as The National Fluid Milk Processor Promotion Board.

Therefore, the contradictory results, the lack of control groups, the questionable protocols and the inability to obtain blinded studies, do not allow to claim without any doubt that chocolate milk is the best supplement compared to the other supplements studied. The number of serious studies on chocolate milk will have to be considerably larger. Furthermore, these studies will have to be done more independently (not financed by the dairy industry, for example) to achieve more conclusive results.

It should be noted that chocolate milk has not been compared to a supplement offering a ratio of 2:1 previously shown to offer better performances than a CHO supplement taken optimally by Berardi et al. 2008 (100). For comparison purposes, a 200lbs (90kg) man who ingests a supplement offering a ratio of 2:1 will consume 72g of CHO/h instead of 85g/h for a chocolate milk supplement taken optimally. So this represents approximately 40g less of added sugar consumed, during a 3 hour recovery, to achieve the same result, if not better.

The composition of the supplement used by Berardi et al. 2008 is also very different from that of chocolate milk; it contained 33% of maltodextrin, 33% of glucose and 33% of whey (100). So in addition to the ratio, the choice of nutrients is important.

4: CHO

Maltodextrin (MD) seems to be the ideal sugar for muscle glycogen resynthesis after an intense effort. Piehl-Aulin et al. 2000 have shown that a supplement containing very high molecular weight polyglucosides such as maltodextrin would be 25% more efficient for muscle glycogen synthesis than a low molecular weight glucose, maltose or oligomer supplement (127). This would be due to the faster absorption rate of sugars by the intestines, as well as an increased rate of gastric emptying. As seen previously, while the addition of fructose to MD (ratio 2:1, MD: FRU) represents a major advantage DURING a long performance (more than 2h30) such as a marathon(128), it seems that for the rapid muscle glycogen resynthesis between two performances, the addition of fructose or galactose to MD offers no advantage (129). Regarding sucrose (glucose: fructose), no advantage was observed concerning glycogen resynthesis when compared to glucose alone (69, 129, 130, 131, 132), nor during the second performance (129 to 131). Again, we notice that the fructose and galactose portion found in chocolate milk is not useful for the post-training recovery.

5: Proteins

As for strength training, the type of proteins added to the CHO as a post-training supplement is important. However, few studies compare the different types of proteins and their effects on the glycogen resynthesis speed during a short term recovery. Morifuji et al. 2010 have shown, in rats, that adding whey hydrolysate to CHO is more efficient for glycogen synthesis than the CHO control group, followed by non-hydrolysed whey and BCAA. Casein ranked dead last, having no significant effect on glycogen synthesis compared to the intake of glucose alone (133). A large proportion of studies on athletic recovery used hydrolysed or non-hydrolysed whey protein isolate as a source of proteins in their mixes. The advantage over the chocolate milk proteins (mainly consisting of casein) is that in addition to being absorbed faster, the whey protein allows a higher protein concentration mix while restricting the volume to be consumed. It is a non-negligible advantage for the athletes as well as for achieving ratios of 2:1, for example.

Lactose

Milk contains 25g of lactose per 500ml. The capacity to break down lactose into glucose and galactose molecules depends on the presence of the lactase enzyme in the small intestine. “Normally” in humans, the presence or activity of lactase is very strong at the beginning of childhood and starts declining after the child is weaned until it almost disappears in adulthood. The person is then unable to digest lactose for the rest of his or her life (134, 135, 136). Between 65 and 70% of the world population is unable to digest lactose once they reach adulthood (137, 138). So only 30 to 35% of the population can actually digest lactose. Why? During the human evolution, four different mutations occurred, namely a major one that occurred in Europe, which kept the lactase gene active and thus allowing some Caucasians to digest lactose during all their life(137 to 139). These European Caucasians travelled, reached America and gave their descendants the possibility to also carry this mutation. Despite this, approximately 21% of North Americans who have problems digesting lactose are Caucasians (140). The ability to digest lactose is directly linked to the quantity of lactase produced by the intestine (134 to 136) and this quantity varies from one person to another. So some people have more difficulty than others to digest this sugar even though it may not be a true intolerance, rather an incomplete digestion that can sometimes be asymptomatic (140 to 143).

Making up 50% of the sugar contained in chocolate milk, we must seriously question the lactose digestion capacity to quickly regenerate the glycogen stores post-training, if we take into account the differences in the quantities of lactase present in the intestines of each individuals. It was shown that adding sugar (144, 145, 146, 147), fat (147) or chocolate (144, 145) in milk slows down the digestion process. This slowing down certainly promotes a better digestion of the lactose by the lactase present in various amounts, but does make digestion more efficient ? Since it can be very difficult for some people, around the world, to digest lactose, chocolate milk could only be used by a very small portion of athletes, which already represent a tiny portion of the population.

Who promotes chocolate milk?

Besides dairy producers in Quebec and Canada, many nutritionists promote chocolate milk as an ideal post-training supplement. The most relevant comment made to this effect by a nutritionist is the comment from Isabelle Charêt, coach and triple medallist in speed skating at the 1994, 1998 and 2002 winter Olympics (148). She says that chocolate milk would be a lot more useful to people who train intensively: “Someone who goes to the gym three times a week has plenty of time to recover. But I still recommend to drink chocolate milk because people in general don’t drink enough milk.” Ah! But that’s the issue! We have to drink milk!

I will not go into further detail on this subject, but very recently (2013), a team from Harvard University acknowledged publicly the need to decrease to less than two portions per day, or to stop all together, our milk consumption (149, 150). The powerful dairy industry lobby, which represents a third of Quebec’s agriculture and 5 billion dollars of Canadian GDP, imposed itself to maintain the dominant position dairy products hold in the Canadian food guide (151). Nonetheless, the following question remains: is it necessary to include chocolate milk in our diet? Many scientists seem to think that it’s not (149, 150, 151, 152).

Conscious of the extent of the damages caused by the overconsumption of added sugars to human health, how can we encourage the consumption of such sugars just to impose a supplement that is increasingly considered as unnecessary to our health?

Conclusion? If you enjoy a glass of chocolate milk once in a while, as a treat, it’s no big deal! But if milk commercials encourage you to drink one after each of your trainings, and you are not an Olympic athlete (and even then…), I hope you’ll think twice about it.

You know the saying: When it seems too good to be true…

 

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