Foods to Help Fight Cold and Flu This Winter
The cold and flu season has arrived and nutrition experts say eating healthy foods is one way of helping your immune system fend off illness. Boosting the body’s immune system is important because it creates, stores, and distributes the white blood cells that fight bacteria and viruses that enter the body.
Keeping the immune system in a position to fend off colds and the flu is essential at any age, but it is especially important as we age because immunity begins to decrease as we get older. According to Samantha Heller, a senior clinical nutritionist at NYU Langone Health, if we get the right nutrients, “we can help our immune systems do their jobs to protect us against viruses like the flu.”
Heller says one way to stay healthy during the flu season is to eat a plant-based diet rich in whole unprocessed foods, similar to the fruits, vegetables, whole grains, and nuts that are part of the Mediterranean diet.
Balanced diets, such as the Mediterranean diet, “present the finest nutritional quality to support the immune system and other physiologic functions,” according to a study published in the July issue of the journal, Frontiers in Nutrition. The study found that balanced diets of healthy foods also provide better protection against COVID-19.
To get a head start on fighting colds and the flu this season, here are six superfoods researchers and nutritionists recommend that provide maximum health benefits:
Salmon tops just about every list of superfoods. In the case of colds and flu, salmon contains vitamin D, which supports the immune system in fighting against viruses that enter the body.
A 2020 study published in the journal, JAMA Network Open, found that people who had an untreated vitamin D deficiency were almost twice as likely to develop COVID-19 as patients who had sufficient levels of vitamin D.
In addition to providing vitamin D, salmon is a good source of omega-3 fatty acids, which are essential to the body and have been shown to strengthen the immune system.
2. Green tea
In some circles, green tea is considered a kind of “Swiss Army knife of hot beverages” because of all its health benefits. The antioxidants in green tea help the immune system fight against bad bacteria and free radicals, which can cause damage to cell membranes, proteins, and may also increase the risk of cancer.
Researchers, however, have long debated whether green tea can actually help fight colds and flu. But a meta-analysis of eight studies involving over 5,000 participants found that green tea’s catechins, which are natural antioxidants that prevent cell damage, can also help the immune system fight against cold and flu. The study was published in July in the journal, Molecules.
3. Foods rich in beta carotene
Beta carotene is the natural compound that gives fruits and vegetables their red, orange, and yellow colors. Beta carotene also helps the body make vitamin A, which supports a healthy immune system. Beets, broccoli, yellow, and winter squash are good sources of beta carotene, as are sweet potatoes.
Anna Taylor, the lead outpatient clinical dietitian at the Cleveland Clinic’s Center for Human Nutrition, says that sweet potatoes support respiratory health by increasing the number of immune cells in the body. This is important for older adults since the body produces fewer immune cells as we age, Taylor said.
Strawberries, blueberries, and raspberries are good sources of Vitamin C, an antioxidant vitamin that has been a popular remedy for the common cold. Vitamin C helps the body to make antibodies, which are proteins that fight off illnesses.
Berries contain anthocyanins, which give certain fruits and vegetables their red, blue, and purple coloring. Anthocyanins have been shown to reduce inflammation, boost the immune system, and fight virus infections.
Berries also contain flavonoids, which are plant compounds that have antioxidant properties and protect immune system cells and other cells from damage, Taylor said.
A January 2018 article reviewing the health effects of berries said that only whole berries or complex berry-derived products have a positive effect on the immune system. This effect results in reduced symptoms of the common cold and an increase in white blood cells, which help to fight infection from bacteria and viruses.
Black beans, kidney beans, white beans, and lima beans are good sources of fiber, vitamin B, and antioxidants. Beans are rich in iron, with white beans having the most iron content of any beans. Beans also contain folic acid, a synthetic form of vitamin B that is used in supplements and added to fortified foods.
Beans are also high in zinc, a mineral that assists in producing T-cells, white blood cells, and other immune cells that help the body fight diseases and viruses. A systematic review and meta-analysis of studies on zinc suggest that zinc supplements may reduce the duration of a cold and the severity of its symptoms, according to an article published in November in the journal BMJ Open.
Taylor recommends eating at least half a cup of cooked beans three times a week. Beans can be used in salads, soups, and chili, for example.
6. Nuts and Seeds
Nuts and seeds have a lot going for them. First, plant-based foods are good sources of vitamin E, one of three major antioxidant vitamins along with beta carotene and vitamin C. Vitamin E supports the growth of T-cells, which also plays a role in fighting cancer.
Secondly, nuts and seeds are rich in omega-6 fatty acids, which the body cannot make on its own, yet, are essential to survival. Studies show that essential fatty acids help in treating disease and improves body composition, as well as mental and physical performance.
Walnuts, specifically, have a very positive effect on the gut microbiome, according to Kate Cohen a registered dietitian nutritionist with the Ellison Institute for Transformative Medicine at Providence Saint John’s Health Center in Santa Monica, California.
The gut microbiome helps to control digestion and benefits the immune system. Walnuts also have more of alpha-linolenic acid (an omega-3 fatty acid) than other types of nuts.