As winter approaches, many of us start to think about strategies to stay healthy through cold and flu season. One of the most accessible and simple ways to do this is to reach for foods and beverages that contain immune-supporting nutrients. But with so many products on the market touting these properties, it can be hard to discern which are actually effective.
Understanding which nutrients are tied to improved immune function and what foods they’re found in is key to feeling empowered in the grocery aisle. We’re here to help with a brief rundown on the immune system-optimizing nutrients and a convenient list of some of the best immunity-boosting beverages.
- Amy Davis, RDN, is a registered dietitian and the owner of Amy Davis Nutrition
- Julie Pace, RDN, is a private practice dietitian and the owner of Core Nutrition Health & Wellness
Immune-Boosting Nutrients
While prioritizing a balanced diet that includes all (or most) of the major food groups is the best way to ensure a healthy, functioning immune system, there are certain nutrients specifically tied to immune function. Here are some of the most impactful nutrients that you’re likely to find in certain beverages:
Vitamin C
When many people feel a cold coming on (or want to ensure they don’t catch one), vitamin C-rich foods, drinks, and products are often what they reach for. “Vitamin C stimulates the production of white blood cells, which are essential for fighting infections, and also acts as a powerful antioxidant, protecting cells from free radical damage,” says Amy Davis, RDN. Free radicals are oxidative compounds that often contribute to many acute and chronic illnesses. Kiwi, citrus fruits, berries, broccoli, tomatoes, and peppers are all great sources of vitamin C.
Vitamin D
Over 40% of Americans unknowingly struggle with vitamin D insufficiency, putting their immune system at a disadvantage. “Vitamin D aids in producing infection-fighting proteins,” explains Julie Pace, RDN. “It also enhances the function of white blood cells and reduces inflammation,” Davis adds. And while vitamin D can be tricky to find in the diet, portobello mushrooms, salmon, sardines, eggs, and fortified foods like milk (cow’s or plant-based), cereals, and orange juice are all great places to look. However, sun exposure is one of the most effective strategies for obtaining vitamin D.
Vitamin E
As a major antioxidant, vitamin E deficiency has been found to impair immune function as this vitamin modulates immune cell function. This fat-soluble nutrient is found in nuts, seeds, avocado, spinach, asparagus, peppers, broccoli, and wheat germ.
Phytonutrients
Speaking of antioxidants, plant compounds (or phytonutrients) of all kinds, whether it’s flavonoids, phenolic acids, or carotenoids, typically exhibit antioxidant benefits. This helps reduce inflammation throughout the body as well as ward off free radical molecules. As you might imagine, phytonutrients are going to be found in plant-based foods, including fruits, vegetables, whole grains, legumes, nuts, seeds, herbs, teas, and other specialty items like coffee.
Zinc
“Zinc plays a major role in the production and proper functioning of immune cells and is also involved in the body’s ability to fight infections,” says Davis. This infection-fighting capacity is related to zinc’s antioxidant properties. “It also provides antiviral support, including blocking coronavirus replication,” Pace adds. Zinc sources include cashews, pumpkin seeds, hemp seeds, legumes, poultry, beef, and oysters.
Selenium
This mineral is another classic antioxidant, further supporting the immune system. Selenium not only acts as an immunomodulator through regulating selenoproteins that protect immune cells, but it also acts as an immunostimulator through actions like anti-tumor activity. Brazil nuts, sunflower seeds, eggs, fatty fish, dairy, mushrooms, and soy products are all fantastic places to find selenium.
Fiber
“A large portion of the immune system is housed in the gut,” says Davis. This is thanks to the significant influence the gut microbiome (a community of over a trillion microorganisms largely located in the colon) has on the immune system. Soluble fiber in particular acts as a prebiotic, or food for healthy bacteria in the biome, helping this microbe community thrive. All fiber-containing foods will contain both soluble and insoluble fiber, but some especially rich sources of soluble fiber include oats, apples, citrus, barley, carrots, flax seeds, avocado, and legumes.
Probiotics
“In that same vein, probiotics are crucial to maintaining a healthy balance of gut bacteria and are key for improving immunity,” says Davis. Probiotic-rich foods introduce more beneficial bacteria to the microbiome, further supporting that system. Probiotics are found in yogurt, cultured cottage cheese, kefir, and other fermented foods such as kimchi, sauerkraut, and kombucha.
8 Immunity-Boosting Beverages
Green Tea
“Green tea is a beverage linked to immune health since it is rich in antioxidants called catechins,” says Davis. Moreover, epigallocatechin-3-gallate (EGCG) is a plant compound found in green tea that is tied to immune system regulation and modulation. And if you’re sensitive to caffeine or prefer to enjoy tea in the evening, no fear, decaffeinated green tea still offers all of these benefits.
Smoothies
Smoothies are tasty, easy-to-prepare beverages that you can load up with immune-boosting nutrients. Reach for berries, kiwi, or citrus for your vitamin C, fortified milk or orange juice for your vitamin D, avocado or spinach for vitamin E, hemp seeds (also lovingly known as hemp hearts) for zinc, dairy or sunflower seeds for selenium, and yogurt or kefir for probiotics. All the plant-based ingredients in your smoothie will provide fiber and plant compounds, too!
Echinacea Tea
As a beautiful bright pink flower, echinacea is packed with immune-boosting vitamin C, selenium, zinc, and plant compounds. “Packed with antioxidants, echinacea offers immunomodulating, anti-inflammatory, antibacterial, and antiviral benefits, making it a powerhouse for immune support,” Pace explains. Plus, the tea made from this popular herb has a lovely mildly earthy, floral taste.
Ginger Tea
“Ginger is known to have anti-inflammatory and antioxidant properties, helping to bolster the immune response” says Davis. In fact, research has even linked this root vegetable to improvement in colorectal cancer markers. Plus, ginger contains an array of plant compounds, can be brewed with any fresh or frozen ginger you have in your house, and is conveniently caffeine-free. Add some honey to your tea to amplify the immune-boosting benefits as this sweetener is chock-full of phenolic compounds that also target inflammation and oxidative compounds.
Yerba Mate
Yerba mate is a South American plant used to brew a tea-like beverage that holds great cultural significance in countries like Argentina, Brazil, Paraguay, and Uruguay. And while it’s been a staple beverage in the indigenous communities of these regions for thousands of years, this drink is starting to gain in popularity in the States. This is thanks, in part, to the impressive health benefits it offers – including on our immune health. Mate boasts a range of plant compounds, including polyphenols and saponins, and one cup contains 13% of one’s daily value for vitamin C as well as four percent zinc. Although this caffeinated beverage can be tricky to track down, Guayakí is a mate brand that can be readily found in grocery stores and convenience stores nationwide. Opt for their loose leaf and unsweetened products for the most immune health benefit.
Bone Broth
Few things are as comforting as a warm mug of bone broth, especially as winter rolls in. It’s just a happy coincidence that this savory beverage is also terrific for our immune health. “Bone broth has been linked to boosting the immune system due to its collagen and glutamine content, which support gut health,” says Davis. These nutrients work by supporting gut lining integrity and gut microbiome health.
Jun
For a healthy dose of immunity-boosting probiotics, green tea compounds, and honey, look no further than jun, the slightly healthier sister of kombucha, which contains no refined cane sugar. You can expect jun to offer a more mild, smooth flavor compared to ‘booch, too.
Golden Latte
As an increasingly trendy beverage, golden lattes feature the superfood turmeric. “Turmeric contains curcumin, which is a powerful anti-inflammatory compound that supports immune health, therefore, golden milk lattes have become a popular option for enjoying turmeric in beverage form,” Davis says. Other spices it features, including cinnamon, ginger, and black pepper, also contain immune-boosting plant compounds. You can easily make this drink at home by warming two cups of your favorite milk and adding a teaspoon or so of turmeric, a drizzle of honey, and a sprinkle of cinnamon, dried ginger, and black pepper.