Let’s discuss nutrition and how to support your immune system as we move into flu season. It doesn’t matter if you are an athlete during the season, or not, it is important to stay healthy so that you don’t miss out on your training. Research shows a link between intense exercise and immune function. Intense training can lead to inflammation, which makes it harder for the immune system to fight illness. Although no one supplement or nutrient can cure or prevent illness, we will be discussing nutrients that are important for optimal health and immune function.
Vitamin D, which is naturally produced by the sun, plays many important roles in the body. Vitamin D is essential for bone strength, cell development, calcium absorption, and immunity. Vitamin D deficiencies can increase your risk of developing a serious illness.
Adults should consume 15 mcg (600IU) of vitamin D daily. It is difficult to get enough vitamin A in your diet, many people don’t realize this. Vitamin D is a rare food that is naturally abundant in Vitamin D. These include eggs, salmon, and mackerel, as well as fortified foods such as orange juice, cereal, and fish. If you are vegetarian or vegan, there is a possibility that you already require Vitamin D supplementation.
Antioxidants (Vitamins C, E,
Vitamins A, C, and E support the immune system by decreasing inflammation caused by oxidative stresses. Many antioxidant-containing foods like fruits, vegetables, and whole grains also contain polyphenols that have been shown to benefit health due to their strong antioxidant and anti-inflammatory properties.
Many antioxidant supplements contain massive doses (>10x the recommended daily intake) per portion. Antioxidant supplements are not recommended for athletes. Supplemental antioxidants (vitamins C and E), can inhibit your body’s natural adaption to training. Instead, aim to consume a diet rich in antioxidant-containing foods like whole grains, fruits, and vegetables. Here are some foods high in vitamins A, C, and E.
Vitamin A red and orange vegetables like sweet potatoes, pumpkins, cantaloupes, mangoes, and peppers.
Vitamin C red peppers and grapefruit, oranges, red bell peppers, grapefruits, kiwis, broccoli, strawberries, Brussels sprouts, and peppers
Vitamin E: almonds, sunflower seeds, avocado, peanuts, oils like avocado and olive oil
Omega-3 Fatty acids
Essential fatty acids cannot be produced by the body so they must be taken in through diet. Omega-3s have been shown to improve brain, heart, and immune function. They also may help with inflammation management, which is a major benefit for overall health.
The three main types of omega-3s that are available are EPA (eicosapentaenoic), DHA (docosahexaenoic), and ALA (alpha-linolenic acids). DHA and EPA are found in fatty fish like tuna, salmon, mackerel, and mackerel. ALA, the plant-form omega-3, can be found in flaxseed oil, walnuts, chia seeds, and ground flaxseed. The recommended daily intake of ALA for men is 1.6 g and 1.1 g respectively for women. Competitive athletes may need higher amounts of omega-3s. This could potentially increase to 2-4 grams daily.
The role of the gut microbiome, which is the total number of bacteria and fungi in the digestive tract, has been demonstrated to be critical in many functions in the body, including energy production, vitamin synthesis, and protection against pathogens. The good bacteria in the gut are called probiotics. A greater diversity of microbiomes can have a positive impact on health.
Probiotics can be found in fermented foods like kimchi and sauerkraut, Greek yogurts, kefirs, cottage cheese, and miso. Consuming prebiotics, which is found in fruits like apples, bananas, and asparagus, can help to support good bacteria in your stomach.
Iron is an essential mineral found in many foods. Iron is an important component of hemoglobin. This helps transport oxygen from the lungs into the tissues. Iron is essential for growth, neurological development, and cellular functioning. It also plays an important part in the development and growth of immune cells. A deficiency in iron has been linked to impaired immune function.
For males, the recommended daily iron intake is 8 mg and for females, it’s 18 mg. Research shows that aerobic exercise increases the need for iron. If iron levels are not met, ATP can’t be synthesized correctly. It is possible to experience early fatigue and decreased work capacity while exercising. Iron status may be compromised in female endurance athletes, who are particularly at risk. Vegetarian/vegan athletes can be concerned about iron intake due to the bioavailability and non-heme iron. Non-heme iron can be found in plants such as leafy greens and whole grains. Heme iron can be found in animal products like poultry, eggs, and meat. This difference in bioavailability is why the RDA for vegetarians/vegans has a 1.8x higher level than that for people who eat meat.
Zinc, an essential nutrient, is required for many functions in the body, including DNA synthesis and wound healing. It also plays a vital role in cellular function. Zinc is essential for immune system development and growth.
For males, the recommended daily intake of zinc is 11 mg and for females, it’s 8 mg. Zinc can be found in many foods, including chicken, turkey, cashews, and chickpeas.