With the arrival of colder temperatures in the winter months also arrives cold and flu season. While it may seem like getting sick at some point is inevitable, there are many nutritional strategies that can be applied (year round, really!) to boost the strength of your immune system and decrease your chances. As a sports dietitian, I am often counseling athletes on the importance of a healthy diet in maintaining a strong immune system to ensure consistent training year round. Today, I am here to share a few top nutritional strategies that have been shown to boost immune health:
- Consume a diet that is adequate in overall calories, balanced among the all three macronutrients, and rich in nutrient dense foods. Chronic calorie deficit over time, whether through failure to meet needs or intentional dieting for weight loss, can lead to impaired immune health in that it decreases the energy available to support normal bodily functions. Calorie deficit without careful consideration of diet quality can also lead to insufficient intake of vitamins and minerals related to immune health, including vitamins C, E, B6, A and D, Folate, Iron, Selenium and Zinc. Aim to include not only fruits and vegetables with each meal, but also quality lean proteins and whole grains too. A few high antioxidant foods to consider in boosting immune health include grapes, blueberries, raspberries and strawberries, nuts and seeds, any dark leafy greens, sweet potatoes and other orange vegetables, beans, fish and whole grains!
- Swap unhealthy (saturated) fats in your diet for healthy (unsaturated) fats, which are both anti-inflammatory and immune boosting. Instead of aiming for low-fat foods, aim to replace sources of saturated fat in your diet for healthy fats, especially omega-3 fatty acids, which support hormone production and help fight inflammation in order to keep our immune system strong. More specifically, essential fatty acids (omega-3’s and Omega-6’s) play a role in the production of eicosanoids, a class of chemical messengers involved in your body’s immune and inflammatory response. These healthy fats can be found in avocadoes, nuts (especially walnuts!), sunflower, sesame and pumpkin seeds, olives, flaxseed and wheat germ, chia seeds and fatty fish varieties.
- Ensure adequate Vitamin D intake for optimal immune strength. While we are able to naturally synthesize Vitamin D through sun exposure, it’s not uncommon for Vitamin D levels to drop off in the winter when colder whether forces us inside more. Low Vitamin D levels have a direct effect not only on bone health, but immune health as well, and it’s never a bad idea to have your levels checked by your primary care physician. To ensure you’re getting enough Vitamin D through diet, aim to consume a few of these foods daily: Cod Liver Oil, oily fish (trout, salmon, swordfish, mackeral, tuna and sardines), mushrooms, fortified cereals, tofu, dairy products, pork and eggs.
- Consume foods with naturally occurring probiotics to improve gut health. Gut health has a direct impact on both the health of our brain and our immune system. By incorporating foods with natural probiotics, including yogurts and cheeses, kefir, sauerkraut, miso, sour pickles and kombucha, you are feeding the healthy bacteria in your gut that in turn can lend to a stronger immune system.
- Flavor your foods with healthy herbs & spices. Many of the herbs and spices that we use to flavor our foods also have potent anti-microbial, anti-inflammatory and immune boosting properties. Garlic, onion, turmeric, ginger and cinnamon are a few herbs and spices that top the list.
- Garlic is not only known for it’s unique and pungent flavor contribution to many dishes, but also it’s role as a potent anti-inflammatory, anti-viral and cancer preventative food. Garlic’s numerous beneficial immune benefits are due to sulfur compounds and being a quality source of vitamin C, vitamin B6, selenium and manganese.
- Onions are not only a quality source of Vitamin C, but also one of the richest sources of flavonoids, especially quercetin, which has been shown to inhibit inflammation. Onions also contain the trace mineral selenium, which helps to initiate the body’s immune response.
- Curcumin is a component of the spice turmeric and helps give it its distinct orange-yellow color. Turmeric is commonly found in curry spices and dishes. Curcumin is traditionally known for its anti-inflammatory effects but in recent decades has also been shown to be a potent immune-modulating agent.
- Ginger, more commonly known for its anti-nausea benefits, also boosts anti-inflammatory and antioxidant activity within the body. Ginger is best consumed uncooked in it’s natural form, so aim to buy ginger whole and use a grater to include it in your dishes where possible.
- Cinnamon is another spice that is not only rich in antioxidants, but also a quality source of manganese, calcium, fiber and iron. The essential oils found within cinnamon have also been shown to boost the immune system since they have antiviral, antibacterial and antifungal properties.
Wintertime doesn’t have to inevitably spell out cold and flu season. To boost your immune system and decrease your chances of getting sick aim to follow some of the tips above, and don’t forget to get plenty of sleep at night too!!
Kristen Chang is the current Co-Chair of Professional Education for VAND. She is an adjunct instructor for Virginia Tech and Radford University and the owner of the nutrition private practice, Real Food For Fuel, LLC.