Be A Pillar Of Immunity

The right combo of supplements — along with rest and a solid diet — can help you fight illness, keeping you training hard through flu season and beyond.

By Dwayne N. Jackson, PhD | March 22, 2016

Intense, high-volume training increases the risk of developing minor upper respiratory illness (a.k.a. the common cold). Most often caused by viral infections, colds in themselves are not considered life threatening to young healthy people. However, for an athlete, catching a cold can lead to poor athletic/exercise performance, missed training sessions, and/or require forfeit from competition.

In this article we give you the lowdown on three supplements that have been proven to decrease your chances of catching a cold, keeping you in the gym and out of bed.

Quercetin

What is it? An antioxidant flavonoid found in fruits, vegetables, and grains. Quercetin has been shown to have potent anti-viral properties and has been reported to boost immunity via upregulation of interferon gamma (IFNγ). Sounds complicated but the bottom line is that it helps your body’s immunity machinery function more efficiently.

What does the research say? A study published in Medicine and Science in Sports and Exercise illustrated that taking quercetin (1000 mg daily for three weeks) reduced upper respiratory illness in the two weeks following a three-day period of exhaustive exercise in cyclists. Most interestingly, none of the measured markers of immunity, inflammation, and oxidative stress were improved in this study, suggesting that quercetin may promote direct antiviral effects. In support, a randomized clinical trial, published in Pharmacological Research, reported that physically active middle-aged people who took 1000 mg of quercetin daily (for 12 weeks) had decreased occurrence of colds.

Dose: Based on these studies, take 1000 mg of quercetin daily, split into two doses. Take one 500 mg dose upon waking and another 500 mg in the late afternoon.

Probiotics

What are they? Live microorganisms (i.e., bacteria and yeast) that, when taken consistently in adequate doses, have health promoting effects. Available commercially now in a great many brands, probiotics increase number of “good bacteria” in our gut and promote overall immunity.

What does the research say? Many well-controlled studies in athletes show that daily probiotic supplementation results in fewer colds and lower severity of cold symptoms. A relatively recent meta-analysis, published in The Cochrane Database for Systematic Reviews, analyzed data from randomized control trials involving probiotic supplementation as a preventative measure for colds in athletes and non-athletes. This large-scaled study (3451 subjects) concluded that daily probiotic supplementation reduced the incidence of colds. Furthermore, probiotics supplements may reduce the risk of gastrointestinal infection, which is a common issue when traveling.

See Also Probiotics Pros

Dose: Based on the research, use probiotics that contain Lactobacillus and Bifidobacterium at a daily dose of approximately 10 billion live bacteria.

Vitamin D3

What is it? A bioavailable and potent oral form of vitamin D. Generally less than 20 percent of the body’s vitamin D needs come from the diet; however, during sun exposure, we get a good shot of vitamin D from the conversion of 7-dehydrocholesterol in the skin. Notably, many people limit exposure to the sun’s damaging UV radiation and, as such, tend to be vitamin D deficient, especially during winter months. Beyond being essential for calcium metabolism and absorption, recent research suggests that vitamin D plays a pivotal role in the regulation of immune responses.

What does the research say? In terms of immunity, vitamin D promotes the production of antimicrobial proteins and immune factors. Low vitamin D status in athletes is associated with low saliva secretion of IgA secretion — an antibody that plays a critical role in mucosal immunity -- and increased risk of respiratory infections. Several studies have reported that vitamin D3 supplements reduce the number of common cold episodes and reduce the use of antibiotics.

Dose: Vitamin D3 dosing at approximately 4000 IU per day (with or without food) has been shown to recover vitamin D status to normal levels within a matter of weeks and significantly elevates saliva IgA and antimicrobial secretion rates in athletes.



About the Author

Dwayne N. Jackson, PhD

Dwayne N. Jackson, PhD, is a professor and scientist in medical biophysics at one of Canada’s top medical schools, the University of Western Ontario. He has over 12 years of university education in physiology and has attended the University of Ottawa, the University of Western Ontario and the Yale School of Medicine. He also has over 20 years of competitive and recreational bodybuilding experience and is an expert in the areas of performance nutrition and supplementation.