Healthy You
7 Foods That Fight the Flu
What to eat and drink to build a stronger defense this winter
AS MANY AS 1.3 million people were hospitalized with influenza during the 2024–25 flu season. This year, be prepared by eating right. “As we get older, our immunity starts to decline, but if we get the right nutrients, we can help our immune systems protect us against infections,” says Samantha Heller, a registered dietitian in New York City.
1. SWEET POTATOES
They’re a great source of beta-carotene, a phytonutrient that supports respiratory and intestinal health and increases immune cells in the body, explains Anna Taylor, lead outpatient clinical dietitian at the Cleveland Clinic’s Center for Human Nutrition. This is important for older adults, since our bodies make fewer immune cells as we age. Taylor suggests roasting sweet potatoes with olive oil, oregano and black pepper.
2. BERRIES
They’re rich in vitamin C, which stimulates production of infection-fighting white blood cells, Taylor says. A 2018 review of studies found that eating berries increased levels of disease-fighting cells, such as natural killer cells (a type of white blood cell) and T cells, in older adults.
3. BEANS
Beans are high in zinc, which helps boost your body’s production of white blood cells. “Zinc deficiency has been linked to immune system dysfunction,” Taylor says. She recommends at least half a cup of cooked beans three times a week.
4. NUTS AND SEEDS
They’re rich in vitamin E, which plays a key role in your immune system by supporting the growth of germ-fighting T cells. Walnuts are an especially good choice, as they have more immune-supporting alpha-linolenic acid than any other nut, says Kate Cohen, clinical nutritionist for the lifestyle medicine program at the Hospital for Special Surgery.
5. KEFIR
Compounds in fermented dairy products such as kefir (which is like a thin, drinkable yogurt) have anti-inflammatory properties that can help the immune system fight viral infections. “Fermented dairy is rich in probiotics, which seem to have a positive effect on the immune system,” explains Libby Mills, a Philadelphia nutritionist and former spokesperson for the Academy of Nutrition and Dietetics.
6. SALMON
It’s one of the few foods that provides vitamin D, which plays a huge role in regulating your immune system, says Jennifer McDaniel, owner of McDaniel Nutrition Therapy in Clayton, Missouri. A 2020 study found people with vitamin D deficiency were almost twice as likely to test positive for COVID-19.
7. GARLIC
It’s rich in a compound called alliin, which may be the source of its immune-boosting power. A 2020 review found that garlic seems to stimulate cells related to immune system function.
Hallie Levine is a contributing writer and an award-winning medical and health reporter.