If you have spent any time in the fitness arena, then you have surely heard about Branched Chain Amino Acids (BCAAs). Chances are you may have even been using them for some time. In the gym, people rave about the tremendous benefits of BCAA’s. They claim it can promote weight loss, enhance athletic performance and improve recovery. So is it all hype or is there any truth behind their popularity.  Let’s look at the research behind BCAA’s and draw our own conclusions.

So what are BCAA’s? BCAA’s are 3 of the nine essential amino acids in humans. They consist of leucine, isoleucine, and valine.  What makes them so unique is that they make up a very large portion of our muscles. In fact, they account for over one-third of the amino acids in muscle protein.  Out of the 3 BCAA’s, leucine is considered by many to be the most important.  Now before you go rushing for a bottle of BCAA’s, realize that you can get them from eating a nice balanced diet. High concentration of leucine can be found in foods such as beans, eggs, nuts, seeds, soy, whey and whole grains.  Isoleucine is also present in fish, dairy, meats, eggs, nuts and soy protein. Finally, valine can be found in meats, soy, dairy, and nuts.  Bottom line here is that a diet composed of lean meats, dairy products and nuts provides a good source of BCAA’s. Athletes may require supplementation to meet higher demands.

Now let’s turn our attention to the data and see what well designed research studies tell us.  In a small, randomized, double-blind, placebo controlled study, Matsumoto and colleagues looked at taking BCAA’s and their effects on muscle soreness and muscle damage. They measured plasma creatinine kinase (CK), lactate dehydrogenase (LDH) and granulocyte elastase (GEL). These are all markers elevated in muscle damage. The results were quite impressive. The people taking BCAA had a 21 percent reduction in plasma CK, a 6 percent reduction in LDH, and a 15 percent reduction in GEL. All of these reductions were statistically significant. A number of other well designed studies have shown similar results.

In a recent study, Sharp and Pearson took the role BCAA further by looking at testosterone and cortisol levels along with creatinine kinase levels. Using a randomized, placebo control design, they had participants perform high-intensity total-body resistance training. Their findings were in line with previous studies showing lower markers of inflammation (cortisol) and damage (CK). In addition, they also showed that athletes supplementing with BCAA group had significantly higher serum testosterone levels.

In terms of weight loss, there is some interesting data. A nice review by Devkota and Layman showed that supplementing with 2.5 grams of Leucine allows for increased fat loss during dieting while protecting lean muscle mass.  However, Cheng and colleagues showed that mice maintained on a leucine poor diet experienced greater fat loss.  Pedrosa and colleagues showed that supplementing with Leucine did not result in increased fat loss.  So the jury is still out on BCAA’s for weight loss.

The beneficial effects of BCAA’s extend far beyond those of muscle recovery for athletes. A review of 11 randomized studies showed that BCAA supplementation improved worsening of brain function (hepatic encephalopathy) seen in patients with liver damage. In addition, studies have also shown in rat models that BCAA supplementation promotes glucose uptake by cells. Finally, BCAA’s have been shown to stimulate appetite and improve nutrition status in both the elderly and patients on hemodialysis.

So there you have it, the scientific research supporting BCAA for muscle recovery. Go ahead and eat that chicken breast, the egg white omelet, or a variety of delicious foods high in BCAA’s. Your taste buds will be happy and your muscles will thank you.

References:

• -Matsumoto K, et al. Branched-chain amino acid supplementation attenuates muscle soreness, muscle damage and inflammation during an intensive training program. J Sports Med Phys Fitness. 2009 Dec;49(4):424-31.
• -Sharp CP, Pearson DR. Amino acid supplements and recovery from high-intensity resistance training. J Strength Cond Res. 2010 Apr;24(4):1125-30.
• -Glyn El, et al. Excess leucine intake enhances muscle anabolic signaling but not net protein anabolism in young men and women. J Nutr 2010 Nov;140(11):1970-6. Epub 2010 Sep 15.
• -Lee IJ, et al. Effect of Oral Supplementation with Branched-chain Amino Acid (BCAA) during Radiotherapy in Patients with Hepatocellular Carcinoma: A Double-Blind Randomized Study. Cancer Res Treat. 2011 Mar;43(1):24-31. Epub 2011 Mar 31.
• -Nishitani S, et al. Branched-chain amino acids improve glucose metabolism in rats with liver cirrhosis. Am J Physiol Gastrointest Liver Physiol 288:G1292-G1300, 2005.
• -Devkota S, Layman DK. (Commentary). Curr Opin Clin Nutr Met Care. 2010;13:403-407.
• -Pedrosa RG et al. Leucine supplementation favors liver protein status but does not reduce body fat in rats during 1 week of food restriction. Appl Physiol Nutr Metab. 2010 Apr;35(2):180-3.
• -Cheng Y, et al. Leucine deprivation decreases fat mass by stimulation of lipolysis in white adipose tissue and upregulation of uncoupling protein 1 (UCP1) in brown adipose tissue. Diabetes. 2010 Jan;59(1):17-25. Epub 2009 Oct 15.

Bottom line: Glucosamine may not be effective for chronic back pain based on this small trial.  Effective treatments for chronic low back pain include non-steroidal anti-inflammatory drugs (ibuprofen, motrin, naprosyn, etc.), opiates (vicodin), acupuncture, and physical therapy.  Each therapy has side-effects that must be discussed with your doctor before starting.

Reference:

Wilkens P, Scheel IB, Grundnes O, et al. Effect of glucosamine on pain-related disability in patients with chronic low back pain and degenerative lumbar osteoarthritis: a randomized controlled trial. JAMA. 2010 Jul 7;304(1):45-52.

The reason this is disturbing is that sibutramine is a prescription only medication that needs to be carefully monitored in patients.  As always, be very careful about what you put in your body. What may seem like a harmless, natural supplement may contain ingredients that can have a  devastating impact on your body.

Reference:

http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm219463.htm

The first study was a retrospective trial reviewing 124 charts of type 2 diabetics between 2003 and 2008. The researcher found that those patients with the lowest levels of vitamin D were more likely to have higher average blood sugar levels.

The second study involved 1,300 Dutch men and women, age 65 and above. They also found that those patients with low vitamin D levels were more likely to have the metabolic syndrome than patients with normal vitamin D levels.

Bottom line: Vitamin D is important and every day we here about more reasons for us to take it. The recommended dose is 1000 IU once a day. As always, please check with your doctor before starting ANY supplement.

Reference:

Endocrine Society, June 19, 2010, news release

To answer this question, let’s turn to most comprehensive evidence we have available so far.  In a recent meta-analysis, the Cochrane group looked at a total of 67 trials with 232,550 total participants.  Included were forty-seven trials with 180,938 participants that had a low risk of bias (adequate randomization, blinding and follow-up), twenty-one trials with 164,439 healthy participants, and forty-six trials with 68,111 participants with various diseases (gastrointestinal, cardiovascular, neurologic, ocular, dermatologic, rheumatoid renal, endocrinologic or other).

The results of these trials showed no beneficial effects on mortality (RR = 1.02; 95% CI, 0.99-1.06).  In fact, the trials with low risk of bias showed significantly INCREASED mortality (RR= 1.05; 95% CI, 1.02 to 1.08) in the participants taking antioxidants.  When the different antioxidants were assessed separately, INCREASED mortality was seen with Vitamin A (RR = 1.16; 95% CI, 1.10-1.24), beta-carotene (RR = 1.07; 95% CI, 1.02 to 1.11) and Vitamin E (RR = 1.04, 95% CI 1.01 to 1.07), and no detrimental effect with selenium (RR = 0.91; 95% CI, 0.76 to 1.09) or Vitamin C (RR = 1.06; 95% CI  0.94 to 1.20).  However, please review my other post about how Vitamin C is NOT effective for the common cold.

The bottom line is that the authors found NO evidence to support the use of antioxidants. In fact there was some evidence that excess intake of Vitamin A, E and beta-carotene may increase your chances of dying.  The current guidelines from the American Heart Association and U.S. Preventive Service Task Force are to eat a diet high in fruits and vegetables as a natural source of antioxidants.  There is no recommendation for adding supplements to your diet.  So please stop spending your money on unnecessary and potentially harmful supplements and just stick to a balanced diet. Your body will thank you for it.

References:

• Kris-Etherton PM, Lichtenstein AH, Howard BV, Steinberg D, Witztum JL, for the Nutrition Committee of the American Heart Association Council on Nutrition, Physical Activity, and Metabolism. Antioxidant vitamin supplements and cardiovascular disease. Circulation. 2004;110(5):637-641.
• Website: http://www.cochrane.org/reviews/en/ab007176.html; accessed 12/08

Vitamin D has a multitude of functions in the human body. It promotes calcium absorption in the gut, help with bone growth and remodeling and reduces inflammation. Current research shows that Vitamin D is involved in the regulation of over 200 genes responsible for cellular growth, differentiation, cell death and blood vessel generation. The cell death (apoptosis) genes are especially important when it comes to considering the anti-cancer effects of Vitamin D.

The best marker to check for Vitamin D status is 25(OH)D, which has a half-life of 15 days. This is done via a blood test by your doctor. The optimal level according to the National Institutes of Health Office of Dietary Supplements is ? 30ng/ml. Unlike people with Kidney disease, we don’t check 1,25(OH)2D in the normal population. 1,25(OH)2D has a short half-life of about 15 hours and is closely regulated by the parathyroid hormone, blood calcium and phosphate levels.

Inadequate intake of Vitamin D is a leading contributor to osteoporosis, which affects 10-12 million Americans. The people at most risk for Vitamin D deficiency include: elderly people; people with dark skin tones, who may require as much as six times the UV light to produce Vitamin D; obese patients, whose fat tissue sequesters the Vitamin D; and breastfed babies who receive small amounts of vitamin D from breast milk.

The current U.S recommended daily allowance for vitamin D is as follows:

• Birth-age 50: 200 IU/day (update: new guidelines coming out soon recommend 400 IU/day)
• Age 51-70: 400 IU/day
• Age 71 and up: 600 IU/day

It is interesting to note that the Canadian Cancer Society and many endocrinologists recommend a daily intake of at least 1000 IU/day. This is difficult to obtain through diet alone. Here is a nice little table from the NIH Health Office of Dietary Supplements website listing food sources of Vitamin D

Finally, a question frequently asked is whether supplementing with Vitamin D3 is better than Vitamin D2. This is an extremely controversial question and as of yet we don’t have a definitive answer. Some studies show Vitamin D3 to be more than three times as effective as vitamin D2 in raising serum 25(OH)D concentrations and maintaining those levels for a longer time. However, new data shows Vitamin D2 to be equivalent to Vitamin D3 in maintaining circulating levels. The bottom line is you should aim to incorporate more Vitamin D rich foods in your diet, allow for moderate sun exposure as recommended by the American Academy of Dermatology, and discuss with your doctor if you should supplement with Vitamin D.

References:

• DeLuca HF, Zierold C. Mechanisms and functions of vitamin D. Nutr Rev 1998;56:S4-10.
• Cranney C, Horsely T, O’Donnell S, Weiler H, Ooi D, Atkinson S, et al. Effectiveness and safety of vitamin D. Evidence Report/Technology Assessment No. 158 prepared by the University of Ottawa Evidence-based Practice Center under Contract No. 290-02.0021. AHRQ Publication No. 07-E013. Rockville, MD: Agency for Healthcare Research and Quality, 2007.
• Armas LAG, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab 2004;89:5387-91.
• Houghton LA, Vieth R. The case against ergocalciferol (vitamin D2) as a vitamin supplement. Am J Clin Nutr 2006;84:694-7.
• Holick MF. Evolution and function of vitamin D. Recent results. Cancer Res 2003;164:3-28.
• Armas LAG, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab 2004;89:5387-91. • Holick et al. Vitamin D2 Is as Effective as Vitamin D3 in Maintaining Circulating Concentrations. J Clin Endocrinol Metab.2008; 93: 677-681.

References:

• Manninen AH. High-protein diets are not hazardous for the healthy kidneysNephrol. Dial. Transplant., March 1, 2005; 20(3): 657 – 658.
• Knight et al. The Effect of Dietary Protein Intake on Kidney Function in Women with Normal or Mildly Abnormal Kidneys. Annals of Internal Medicine 2003;138: I-51.

To answer this question, I turned to the Cochrane database. Their systematic review of thirty (yes thirty!!!) trials involving 11,350 participants showed that regular ingestion of Vitamin C had no effect on the common cold incidence in the general population. However, in a subgroup of 642 marathon runners, skiers and soldiers on sub-arctic exercises had a reduction in the incidence of the common cold by almost 50%.

Bottom line is that for most people megadoses of Vitamin C is not beneficial for fighting the common cold.

Hemil H, Chalker E, Treacy B, Douglas B. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews 2007, Issue 3. Art. No.: CD000980. DOI: 10.1002/14651858.CD000980.pub3.

The limited number of studies looking ONLY at tribulus terrestris alone (most products on the market are NOT just tribulus) show that it is NOT effective for getting more muscles or improving exercise performance. Antonio et al. did a randomized control trial using 15 athletes performing resistance training. The dose used was 3.21mg/kg of body weight versus placebo. The trial lasted eight weeks and at the end they found NO changes in body weight, percent fat, total body water or mood states that were statistically significant between the tribulus group and the placebo group.

HOWEVER, there is some MINIMAL evidennce that Tribulus may have some benefit in patients with coronary heart disease (greater chest pain free intervals), and some MODERATE evidence of its benefits in male infertility (Tribulus increases sperm count and libido as demonstrated in a study by Prtoich et al.)

As always here are the references so you can evaluate the studies for yourself.

1. Wang, B., Ma, L., and Liu, T. [406 cases of angina pectoris in coronary heart disease treated with saponin of Tribulus terrestris]. Zhong Xi Yi Jie He Za Zhi or (Chung Hsi I Chieh Ho Tsa Chih) or (Chinese Journal of Modern Developments in Traditional Medicine) 1990;10(2):68, 85-87
2. Antonio, J., Uelmen, J., Rodriguez, R., and Earnest, C. The effects of Tribulus terrestris on body composition and exercise performance in resistance-trained males. Int J Sport Nutr Exerc.Metab 2000;10(2):208-215.
3. Protich, M., Tsvetkov, D., Nalbanski, B., Stanislavov, R., and Katsarova, M. [Clinical trial of a tribestan preparation in infertile men]. Akush.Ginekol.(Sofiia) 1983;22(4):326-329

In case any one is wondering what is gout, here is a great definition from the Mayo Clinic website (http://www.mayoclinic.com/health/gout/DS00090): a form of arthritis that’s characterized by sudden, severe attacks of pain, redness and tenderness in joints.

Reference:

Choi, KH. Purine-rich foods, dairy and protein intake, and the risk of gout in men. NEJM. 2004;350;1093-1103.