Optimal immune function depends on many things, and adequate nutrition is one of them. It’s estimated that 70% of your immune system is in your GI tract. It’s hard to separate fact from fiction with so many products marketed to promote a stronger immune system. The truth is that the best way to strengthen your immune system is by eating nutrient-dense whole foods.
Many nutrients are associated with improving immunity including protein, omega-3 fatty acids, fiber, vitamins A, D, and C, zinc, iron, and selenium. Vitamin D has received the most attention with a recent study linking vitamin D deficiency to COVID-19 risk. However, there isn’t one food or nutrient that can prevent or treat COVID-19. If your diet is lacking in specific nutrients, talk with your health care team before starting any supplements. We eat food, not individual nutrients. So, to support immunity and help manage blood glucose, try adding these nutrient-dense low-carb foods to your meal plan.
- Chia Seeds
Chia seeds are a nutrition powerhouse containing protein, fiber, omega-3 fatty acids, iron, and selenium. Two tablespoons of chia seeds adds 10 grams of fiber and 5 grams of protein to your day. With their high fiber and protein content, chia seeds can help to balance blood glucose. Fiber also works to keep you regular and removes other toxic substances. Try chia seeds in a smoothie, cereal, salad dressing, baked goods, or chia pudding.
Salmon is a fatty fish high in omega-3 fatty acids which have anti-inflammatory effects. Salmon also contains vitamin D and selenium which are required for immune function. Wild-caught salmon contains more vitamin D than farmed salmon. One 3 ounce serving of wild-caught salmon contains more than half of your daily needs for vitamin D. Salmon is a good source of protein and adequate protein intake is important for immunity because it produces antibodies that help the gut barrier.
Broccoli contains fiber, iron, and vitamins C and A. Broccoli is a cruciferous veggie which has been linked to lowering cholesterol, detoxification, and cancer prevention. Broccoli also contains powerful antioxidants that decrease inflammation. In general, people who regularly eat vegetables have lower inflammatory markers. One cup of cooked broccoli gives you 5 grams of fiber and meets your daily needs for vitamins C and A. Try broccoli raw, steamed, or roasted instead of boiling to maximize its nutrients.
Mushrooms grown in the sunlight or treated with UV light are a good source of vitamin D. But not all mushrooms contain vitamin D, so check the Nutrition Facts panel to see if the mushrooms contain vitamin D. One portabella mushroom with UV light exposure may meet your daily needs for vitamin D. Mushrooms are also a good source of selenium. Try mushrooms as a meat replacement in a recipe.
Fermented foods contain probiotics, or “good” bacteria and yeasts, that work hard to support your gut health. When shopping for sauerkraut, look for brands that state “live and active cultures” on the label. Shop in the refrigerated section because heat kills these friendly bacteria. Sauerkraut also contains vitamin C and iron. Adding foods high in fiber such as fruits, vegetables, and whole grains will help probiotics work even harder.
- Red bell peppers
Red bell peppers contain almost 3 times more vitamin C than an orange. Vitamin C helps with iron absorption. They are also a great source of Vitamin A. One half of a red bell pepper meets your daily needs for vitamin C and A. Add peppers to a salad, sandwich, soup, or eat as a snack.
- Pumpkin seeds
Pumpkin seeds, or pepitas, contain fiber, protein, iron, and zinc. They also contain antioxidants to help reduce inflammation. Pumpkin seeds can be eaten with or without the shell. Try pumpkin seeds as a snack or in yogurt, cereal, or on a salad.
Avocados are high in fiber and contain vitamins A and C. One-half of an avocado contains 5 grams of fiber. Avocados are high in healthy fat which helps to absorb fat-soluble vitamins A and D. Add avocado to eggs, sandwiches as a mayo replacement, or enjoy some guacamole dip.
Ginger is known as a natural remedy for nausea and stomach problems. Ginger doesn’t provide vitamins or minerals but it’s rich in antioxidants and may help your respiratory system. Try adding whole fresh ginger to your food or drinks such as ginger tea.
Spinach is loaded with vitamin A, and contains vitamin C, fiber, and iron. Spinach also contains antioxidants to support your immune system. Avoid overcooking spinach to maximize its nutrients. Try fresh spinach for the base of a salad or add fresh spinach to soups, pasta, or sauce.
This year, a flu shot is very important as both the flu and COVID-19 are contagious respiratory illnesses. ADA recommends flu shots for everyone with diabetes, so be sure to get one!
by Christine McKinney, RD LDN CDE