Sick Of Being Sick? Here's Exactly What Doctors Eat To Boost Their Immunity

The strength of one's immune system plays a large part in the body's overall resilience and adaptability. Therefore, I believe that incorporating foods (along with lifestyle practices) that support and strengthen the immune system on a regular basis is key to vital health. In my diet, I often incorporate mushrooms, as they are known for their immune-strengthening benefits; garlic, as it contains antiviral, antibacterial, and antifungal compounds; and fermented foods, as they support the health of the microbiome by introducing healthy bacteria to the digestive system. I also love to incorporate lots of herbs and spices into my meals (like turmeric and ginger) as they offer anti-inflammatory and immune-boosting benefits. Coconut oil is another favorite of mine as it contains a compound called lauric acid, which has been shown to enhance immunity, improve heart and thyroid health, and has antifungal, antibacterial, and antiviral qualities.

I sip on mushroom elixirs from Four Sigmatic. Chaga, lion's mane, cordyceps, and reishi are not only fantastic immune boosters, but they are also adaptogens! I also make sure I get at least a spoonful of extra-virgin coconut oil on a regular basis, either melted in some green tea, blended in a smoothie or straight off the spoon. I love having green juice with dandelion with no fruit other than lemon. It's also about what I don't eat. I typically intermittent fast in the morning, which is a great way to strengthen the immune system.

When I'm feeling under the weather, I do a whole protocol of foods and practices to support immunity. I take elderberry syrup for its antimicrobial properties and cod liver oil for its vitamin A to support immunity. I consume sauerkraut and apple cider vinegar to build beneficial gut flora, and I gargle with warm salt water. Beyond that I rest and try to get fresh air and sunshine.

I eat to boost my immunity by focusing on nutrient-dense foods that are high in zinc. This mineral is foundational for great immunity. My favorite sources are pumpkin seeds and oysters. Pumpkin seeds are super versatile—I'll drop them in the blender to boost any smoothie, add them to omelets and salads, and add them to sautéed greens. Oysters are my other favorite immunity superfood. They are No. 1 on the Brain Food Scale and nature's top source of zinc: over 500 percent of the RDA in just six oysters. Finally, the largest component of your immune system is your gut, and so I regularly eat fermented foods like kefir, sauerkraut, and kombucha.

I make sure to eat plenty of foods containing zinc like lean meats and poultry, oysters, crab, and chickpeas as well as mushrooms and fermented foods. Fifty to eighty percent of your immune system is centered around your gut. The bacteria in the gut (the microbiome) actually have a profound effect on the immune system. Fermented foods help to promote a healthy balance of favorable bacteria in the gut. This stimulates the immune system in a favorable way readying it as the first line of defense against pathogens such as harmful bacteria or viruses. An imbalance of unfavorable bacteria provokes the immune system distracting the immune system and draining its energy. Mushrooms help to support the immune system by providing a number of immune-system-supporting nutrients such as B vitamins, vitamin C, and essential minerals such as calcium, protein and fiber.

For immunity, I avoid grain, dairy, nightshades, and excess stress. They all poke holes in my gut leading to a hyperactive immune system. Leaky gut not only promotes inflammation and jump-starts the development of chronic disease, it can suck up all your energy, making it harder for your body to fight off a cold, flu, or even weight gain. I eat a variety of fermented foods and fiber (35 to 50 grams/day) to maintain stability in the quantity and diversity of healthy microbes in my body. My favorites are coconut kefir, kimchee, natto, and sauerkraut. I keep a diet of foods rich in soluble fiber, like flax and chia seeds, beans, and legumes, as well as one pound of cruciferous vegetables, like broccoli and Brussels sprouts, daily. Together, these foods nourish my gut and boost immunity.

I am fortunate that I am hardly ever sick and I credit my love for mushrooms as my go-to food for this track record. Mushrooms can strengthen the immune system particularly in the winter. They are a great source of vitamin D, which is important in immune function and are also rich in protein, fiber, vitamin C and B vitamins. Mushrooms contain beta-glucans, which have been long known for their immune-enhancing properties. Medicinal mushrooms like reishi, shiitake, and maitake are particularly powerful boosters. These mushrooms may activate white blood cells, which prevent infection. Simply put, mushrooms are my winter flu vaccine.

— Joel Kahn, M.D., mbg class instructor and author of Your Whole Heart Solution

Mushrooms are among my favorite immune-boosters. Rich in 1,3-beta glucans, sometimes referred to as "biological response modifiers" because they influence the activity of the immune system, they are potent stimulators of NK-cells1 (the natural killer cells of the immune system that help target virus-infected cells as well as cancer). One of my favorites are shiitake mushrooms. They are flavorful and make a great addition to any soup, like miso. Other immune-boosting mushrooms include reishi, maitake, and vitamin D-rich matsutake, which have also been found to induce cell death in an experimental model of liver cancer.2 At the first sign of a tickle in my throat or the sniffles, I reach for an immune-boosting soup made with shiitake mushrooms. If I do this early enough, I often feel better by the next day.