I don’t know about you, but cold and flu season always stresses me out. I have never had the dreaded flu (knock on wood) and really do not want to see what it’s like! I do work in a hospital, surrounded by patient’s with the flu, so I got to thinking about ways to strengthen my immune system naturally. Eating a variety of nutritious foods with distinct vitamins and minerals is the key to staying energized with proper nutrition and, as an added bonus, will definitely benefit your immune system! Of course, no food will magically fend off the flu, but certain nutrients will lead us in the right direction of enhancing our immune system. Aiming to get our daily intake of immune-boosting nutrients from a variety of foods, especially those that are in season, is a great game plan to follow. Listed below are a variety of different foods/food groups that contain natural immune boosting goodness!
One nutrient we may not think about when it comes to the immune system is Vitamin A. Vitamin A supports our skin, which we know is our first defense against bacteria, viruses, and germs in general! This vitamin can ALSO act as a antioxidant! Some good sources of Vitamin A include foods like sweet potato, carrots, red bell pepper, apricots, egg, organ meat, salmon, leafy greens, broccoli, mango, cantaloupe, squash, and some fortified foods like milk and cereal.
When it comes to immune boosting micronutrients, Vitamin C is probably the most well known. This vitamin protects you from infection by stimulating antibodies to form, repairs and grows tissues, assists in wound healing AND just when you thought it couldn’t get any better, also acts as an antioxidant which protects cells. Although no nutrient may actually keep us from getting sick, Vitamin C has been proven to “have a modest but consistent effect in reducing the duration and severity of common cold symptoms”. You can up your intake of Vitamin C by eating more citrus fruits and leafy greens, bell peppers, brussel sprouts, strawberries, papaya, and tomato juice. Keep in mind, many foods are also fortified with vitamin C.
Vitamin D is another well known immune system modulator. This vital vitamin helps express and activate many immune cells and allows the body to absorb calcium for strong bones. Not only does it directly impact bone health and strength, but also directly impacts immune health. Vitamin D has even been proven to decrease the events related to respiratory tract infections. I see a lot of patients who are deficient in Vitamin D, which is much more common than you would imagine. You may need to have your Vitamin D levels checked as levels tend to drop off with age because skin cannot synthesize vitamin D as efficiently. Levels also seem to drop in the winter when most of us are inside more. Plan to get more Vitamin D in your daily routine by getting at least 15 minutes of daily sun exposure and eating more vitamin D-rich foods like oily fish (aka trout, salmon, swordfish, mackerel, tuna and sardines), mushrooms, tofu, dairy products, pork, eggs, and fortified cereals.
Vitamin E is also a powerful antioxidant that helps your body fight off infections by neutralizing free radicals! Get some vitamin E in your diet by consuming sunflower seeds, sunflower or safflower oil, almonds, peanuts (or peanut butter), hazelnuts, and fortified cereals.
Zinc helps the immune system work properly by lowering inflammation and also helps wounds heal. Add more lean meat, poultry, seafood, milk, whole grain products, beans, seeds and nuts, yogurt and chickpeas.
More foods and nutrients to focus on for a natural immune system boost:
Protein is vital because the body uses the amino acids to build and repair tissues, maintain cells in the body, make hormones and enzymes, support a healthy immune system, and for A LOT of other important roles! Basically protein plays a role in forming the cells that operate the immune system. Amazing right? Add some lean protein sources into your diet this week. Some of these include lean meat, poultry, eggs, dairy, seafood, beans, peas, soy products and nuts and seeds.
Not only do probiotic-containing foods contain beneficial bacteria that help maintain a healthy digestive tract, those probiotics may also strengthen the immune system and prevent the common cold and upper respiratory infections, according to the latest research . Reach for foods such as miso, kimchi, sauerkraut, yogurt and kombucha. Yogurt (especially Greek yogurt) is also high in protein and calcium!
Garlic, which may cause some short term bad breath, may also boost your immune system in the long run! Garlic has sulfur-containing compounds (like Allicin) that help build up white blood cells which fight infection. Garlic is also touted as a potent anti-inflammatory, can reduce cholesterol and blood pressure, and improve circulation and immune function. Adding fresh garlic to recipes is an easy way to get a diversified immune booster into your diet!
We have talked about seafood, nuts, and seeds in many of the groups listed above, but one more reason to reach for these foods is attributed to their Omega 3 and Omega 6 fatty acids. These fatty acids assist in increasing the activity of white blood cells that fight off harmful bacteria, support hormone production, and help fight inflammation. Increase your intake of salmon, trout, halibut, tuna, avocadoes, seeds, olives, and wheat germ for added immune boosting benefits.
One of my personal favorite foods, mushrooms, are often overlooked when it comes to veggies. But don’t dismiss them too quickly! Mushrooms are proven to have anti-allergenic, cholesterol lowering, antiviral and antibacterial qualities in many studies. Along with this long list of attributes, they also contain prebiotics to stimulate the growth of gut microbiota!
Last but not least, polyphenols, which are aromatic compounds found in berries, vegetables, grains, chocolate, coffee, olive oil, and tea may initiate immune responses and (as an added bonus) help prevent atherosclerosis by increasing vasodilation.
Increasing your intake of these foods may be easier than you think! Head out to your local farmers market to get affordable fresh foods that are in season, as these foods tend to contain nutrients you need during the months they are grown in. Another easy way to incorporate these foods in your diet is to prepare meals for the week ahead or buy frozen fruits or vegetables which are usually very economical and can save time, plus flash frozen fruits and veggies are very nutritious!
Bottom line: keep your immune system in tip top shape by eating a variety of nutritious foods, exercise and get your heart rate up regularly, and last but not least, get enough sleep!
By Brooke Brown, MS, RDN, LDN
A clinical dietitian based in Birmingham, AL, and owner of brookie’s bites LLC. She blogs at brookiesbites.com. Follow her on Instagram @brookiesbites