Wherever you are in the world, your own and your family's immune health is probably on your mind. Diet is one of the most direct levers you have: certain immune boosting foods supply the vitamins, minerals and plant compounds your immune system runs on, from vitamin C and zinc to antimicrobial compounds like allicin and gingerol. Below are the foods that boost immune system function most reliably, followed by three practical recipes for using them: turmeric chicken soup, shiitake mushrooms and homemade sauerkraut.
Foods that boost immune health
These are the immune boosting foods with the most consistent evidence behind them, and the mechanism each one works through.
Citrus fruits and peppers: Oranges, lemons, grapefruit and bell peppers are among the richest sources of vitamin C, which supports the production and function of white blood cells.
Garlic: Contains allicin, a sulphur compound with antimicrobial activity that forms when garlic is crushed or chopped.
Ginger and turmeric: Warming, antioxidant spices with anti-inflammatory compounds (gingerol and curcumin) that show up in traditional cold and flu remedies for a reason.
Shiitake and other mushrooms: A source of beta-glucans, plant fibres shown to modulate immune cell activity.
Fermented foods: Sauerkraut, kimchi, yoghurt and kefir feed the gut microbiome, where roughly 70% of immune tissue lives.
Leafy greens and orange vegetables: Spinach, kale, carrots and sweet potato supply vitamin A and beta-carotene, both involved in maintaining the mucosal barriers that are a first line of immune defence.
Zinc-rich foods: Support the immune cells that depend on zinc to function properly, and are found in poultry, shellfish, seeds and legumes.
With those foods in mind, here are three practical recipes that put them to work.
Immunity-boosting chicken and turmeric soup
Soup is food for the soul, and chicken soup is a classic of immune health — enormously nutritious, particularly when made with homemade bone broth. That said, I usually just use vegetable or chicken stock and it still does the job. This version includes fresh turmeric and ginger, two powerful antiviral, antioxidant, warming spices. I also add the garlic right at the end of cooking, which captures more of its flavour in the soup and preserves more of its antibacterial properties.
Ingredients
1 tbsp olive oil
½ small yellow onion, finely chopped
2 large carrots, chopped
1 medium sweet potato, chopped
4 cloves garlic, minced
2–3 boneless skinless chicken breasts, chopped
1 thumb fresh turmeric
1 thumb fresh ginger
½ tsp sea salt, to taste
3 cups chicken bone broth, or vegetable/chicken stock
1 tin full-fat coconut milk
1 small head kale, chopped
Instructions
Heat the oil in a large pan over medium heat. Add the onion and sauté, stirring occasionally, until translucent — about 5 to 8 minutes. Add the carrots and sweet potato and keep sautéing, stirring occasionally, until the vegetables have softened but remain al dente, another 3 to 5 minutes.
Add the chopped chicken and cook just long enough to brown the meat, 2 to 3 minutes.
Add everything else except the garlic, stir well and cover. Cook at a gentle simmer for at least 30 minutes, stirring occasionally. Then stir in the minced garlic, serve and enjoy.
Shiitake mushrooms
Shiitake are among the most powerful medicinal mushrooms you can buy in a supermarket. A 2015 study of 52 healthy men and women aged 21–41 found that eating shiitake improved cell effector function and enhanced gut immunity, with an overall anti-inflammatory effect. The trial ran four weeks, with participants consuming 5–10g of mushrooms daily.
I add shiitake to soups, risottos, stir-fries and eggy breakfasts, or just eat them on sourdough toast with local avocados and miso paste. They are deliciously meaty and moreish.
Sauerkraut
A healthy, diverse microbial environment in the gut is essential to proper immune function — roughly 70% of immune tissue lives there. Sauerkraut and pickled vegetables nourish the gut microbiome twice over, supplying both fibre and beneficial bacteria: they are prebiotic and probiotic at once. Sauerkraut is also one of the cheapest and easiest ways to get fermented food into your diet. All it takes is a good big organic cabbage and some salt.
Ingredients
1 medium organic cabbage (about 500g)
4 tsp sea salt (not table salt)
Equipment
1 large sterilised jar
1 smaller sterilised jam jar that fits inside the larger one
A large ceramic or glass mixing bowl
Instructions
Shred the cabbage thinly and put it in the mixing bowl. Add the salt and leave it for 30 minutes. Then squeeze and massage the cabbage for 5–10 minutes to draw out as much liquid as you can.
Transfer it to the big jar, pressing down with the little jar until all the water sits above the cabbage. Fill the little jar with water to weigh it down, and cover with muslin cloth or kitchen roll.
Leave at room temperature for 4–5 days, checking daily that the liquid still covers the cabbage. As long as it stays fully covered in the brining liquid, it will keep for months in the fridge. If it looks or smells off, throw it out and start again. Otherwise, dig in.
Recommended dose: 2 tablespoons a day.
References
Cited by the original article:
Dai et al. (2015) Consuming Lentinula edodes (Shiitake) Mushrooms Daily Improves Human Immunity: A Randomized Dietary Intervention in Healthy Young Adults. J Am Coll Nutr. 2015;34(6):478-87.
