Last year around this time I touched on nutrition and our immune system. I just wrote an updated article for a Team Red White and Blue on the is subject, and I wanted to share it with you guys too. Here you go…let’s not get sick this winter!
As athletes, we put so much time and effort into training, that staying healthy is a big deal. Our immune systems must work harder than the average person as we are constantly bombarding it with stress hormones and pro-inflammatory proteins. While there is a fine balance between needing to have a stress response to create the desired adaptations from exercise, we can help to minimize the additional damage with healthy nutrition.
We’re moving into cold and flu season, so here are some nutrition tips to help maintain a healthy immune system. Remember, always consult with your physician before taking or adding in a supplement. Always try to consume your nutrients first with whole foods before supplementing.
- Consume enough carbohydrates and fats for your training: nothing depresses the immune system more than a diet too low in carbohydrates, or too low in fat. If you find yourself getting sick, look at your overall carbohydrate levels and make sure yours are adequate. Most endurance athletes require around 3-5g/kg of carbohydrate per day (during periods of moderate training). During long workouts, take in 30-60g of carb per day. Shoot to have daily fat intake levels around 20-35% of daily calories.
- Low levels of Vitamin D: athletes low in Vit. D have an increased incidence of illness. Vitamin D increases anti-microbial peptides and lymphocyte activation. Best sources: the sun (especially true for winter when we get less sun), oily fish, mushrooms, fortified foods. Aim for at least 600IU/day.
- Low levels of Vitamin C: Vit. C is an antioxidant that has anti-inflammatory and anti-pathogenic properties. While some antioxidants have been shown to impede exercise induced adaptations, Vit. C has not. Runners that supplemented with Vit. C for 3 weeks prior to an ultra-marathon were less likely to develop a upper respiratory infection post run (33% vs 68%) than those runners that did not. Best sources: peppers, dark green leafy veggies, broccoli and citrus fruit. Aim for at least 75-90mg/day.
- Prebiotics/Beta-Glucan: Many athletes have heard of probiotics, but not prebiotics. Prebiotics are quickly becoming just as important though. These are specialized plant fibers that are non-digestible (soluble fiber) and feed probiotics. Beta-glucan is a prebiotic found in oats and barley that has been linked to a healthier GI tract and boosted immune system. Other sources include: beans, legumes and vegetables like asparagus and onions.
- Probiotics: While prebiotics feed probiotics, probiotics feed our GI tract’s healthy bacteria. There is a lot of great research coming out on the numerous benefits of a healthy gut. For athletes, one benefit is an increased immune system. Probiotics can be found in supplement and food form. Food sources: fermented foods like sauerkraut, kimchi, and kefir. Supplements can be in powder form or tablet. If taking a supplement, look for CFU (colony forming units) in the billions. If you see a supplement that touts CFUs is in the millions, keep looking.
- Zinc: Evidence shows that zinc can increase the response rate of immune cells, so if taken at the onset of a cold, can reduce duration and severity of the cold. Unfortunately, there has been no clear data on how much zinc one needs to take to achieve this benefit. One study showed taking a zinc lozenge every few hours was enough to shorten a cold. Too much zinc taken for too long can lead to a toxicity. Best sources: beef, beans, seeds, dark leafy greens.
- Green Tea-EGCG: Epigallocatechin-3-gallage (EGCG) is a compound found in green tea. It’s been shown to fight inflammation and boost anti-viral activity against viruses like retrovirus, the flu and even hepatitis. Matcha green tea powder can be added to smoothies or yogurt, however the taste is acquired. Instead, drink green tea daily (5 cups have been shown to be the most beneficial, however give it a go by just adding in 1 cup).
- Quercetin: A flavonoid, which is a plant pigment found in many fruits and vegetables has been shown to be effective in reducing the inflammatory response from an upper respiratory infection, in addition to blocking the virus’s replication. Sources include: onions, capers, citrus fruits, apples, berries, and black and green tea.
More Controversial but with some good research:
- Bovine Colostrum: Yes, this one sounds a bit controversial. I’m including it here as there is some good research on it and the immune system. This isn’t as practical as the others due to no fresh food sources, however I wanted to include it. Colostrum is the pre-milk fluid produced in the mammary glands during the first 2-4 days after giving birth and contains numerous antibodies and immune factors. Bovine colostrum increases salivary IgA, which in turn helps prevent upper respiratory tract infections. Usually found in powder or capsule form from cows.
- Astragalus Root: This root has been used in ancient Chinese medicine for the past thousands of years. It is called an adaptogen, which means it helps protect the body from stress (physical, emotional, etc). Research has shown both anti-bacterial and anti-viral properties with benefits to those with weakened immune systems. There is some evidence that shows if you have an auto-immune disorder, it will interfere with your medicine. Please consult your physician before taking this as there are no food sources that I can recommend.
Good nutrition is key to a healthy body, training and performance. Shoot for a balanced nutrition plan that includes proper calories and macronutrients, fruits, vegetables, whole grains with soluble fiber, fermented foods, lean protein and green tea. With just those suggestions, you’re on your way to a healthy and cold/flu free winter. Remember that sleep is also a key. Happy Training!