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We could all use a little help staying healthy this season – and these immune system supporting foods and suppliments might be able to help. We’ve pulled together seven ingredients that are easy to add to your daily rotation, along with information about what and how they’re believed to help. Don’t forget to wash your hands, too!
Immune System Supporting Ingredients
BLACK TEA is rich in a group of pathogen-fighting compounds that can protect against a variety of viral infections. Tea leaves contain naturally occurring compounds, including polyphenols, catechins and alkaloids like caffeine, theobromine and theophylline that defend the plants against invading pathogens such as bacteria, fungi and viruses. Older studies show black tea can almost completely inhibit the infectivity of influenza virus. And in one study, black tea extract, rich in flavanol compounds called theaflavins, inhibited herpes simplex virus type 1 (HSV1) infection. Try this: Purée strong-brewed black tea with grated ginger, frozen mango and Greek yogurt for a flu-busting breakfast; steep black tea bags in hot water then use as a broth to cook brown rice, garlic and onions.
SHIITAKE MUSHROOMS are loaded with beta-glucans, antiviral compounds that have been shown to inhibit viral replication and enhance immune system function. In one study, people who ate shiitake mushrooms for four weeks showed improved markers of immunity, as well as reduced inflammation. Other studies show shiitake mushrooms also have significant antibacterial and antifungal properties, and they protected against 85% of the yeasts, molds and other organisms they were tested on. Try this: Thinly slice shiitake mushroom caps, toss with melted coconut oil and minced garlic and roast until crisp; stir-fry shiitakes, slivered carrots, broccoli, sliced red peppers and minced ginger in sesame oil and tamari then toss with cooked soba or rice noodles.
YOGURT contains an abundance and variety of probiotics that may aid in fighting viral infections. In one review, 28 trials found that probiotics had a positive effect on respiratory tract infections (RTIs). Other studies have found probiotics can enhance respiratory tract immunity, speed recovery and lessen the severity of respiratory infections caused by the influenza virus. They’re thought to work by enhancing overall immune function, interacting directly with the virus and/or producing antiviral compounds. Probiotics may protect against other viral infections, including some types of coxsackievirus, HIV-1 and viruses that cause diarrhea. Try this: Line a mesh strainer with cheesecloth, pour in yogurt, place over a bowl and let stand overnight for easy yogurt cheese; whisk yogurt with apple cider vinegar, dried dill and minced garlic and chives for a healthy dressing.
GINGER has long been used in traditional medicine to treat colds and flu, and modern studies show it has measurable antiviral benefits. In one study, fresh ginger protected against HRSV (human respiratory syncytial virus, a major cause of lower respiratory tract infections) by blocking the virus’ ability to attach to cells and stimulating the release of compounds that help counteract viral infections. Try this: Cut peeled ginger root into matchsticks, sauté in olive oil until crisp and use as a topping for soups or salads; simmer ginger slices in milk or coconut milk, strain then whisk in turmeric and honey for a creamy, soothing beverage.
APPLE CIDER VINEGAR is another traditionally used antiviral and a number of modern studies have shown the antimicrobial activity of apple cider vinegar against a variety of pathogens. Researchers suggest apple cider vinegar may work by a variety of mechanisms, including the antiviral properties of apples and the presence of probiotics that occur during the fermentation process. Try this: Steep dried elderberries and sliced ginger in apple cider vinegar then strain and add honey for an easy oxymel (herbal tonic); whisk together apple cider vinegar, honey, mustard and olive oil for a sweet, creamy dressing.
GARLIC contains powerful compounds, including allicin, diallyl trisulfide and ajoene, that fight viruses, including influenza, rhinovirus, cytomegalovirus (a type of herpes virus), herpes simplex, HIV, viral pneumonia and rotavirus. In one study, people who took allicin extract over a 12-week period had significantly fewer colds than the placebo group, and those who did get a cold recovered faster. Try this: Roast whole heads of garlic, skin-on, until cloves are soft then let cool and peel off skins; finely mince raw garlic and add to a dressing of olive oil, lemon juice and minced thyme.
CINNAMON has been used in herbal medicine for hundreds of years, and chemical profiling shows its active compounds have antiviral, antimicrobial, immunomodulatory and anti-inflammatory effects. In one study, cinnamaldehyde, the compound that gives cinnamon its characteristic flavor and smell, inhibited the growth of the influenza virus. Cinnamaldehyde also inhibits Listeria and Escherichia coli in foods and protects against a variety of yeasts and fungi, including Candida albicans. Try this: Add cinnamon, cardamom, vanilla extract, and coconut milk to oatmeal for a chai-spiced breakfast; add cinnamon and cocoa powder to your morning coffee.
Supplements to Support Your Immune System
Elderberry, an extract used in herbal medicine to treat infection, has potent antiviral activities against respiratory pathogens and influenza viruses. Research has found elderberry might shorten the length of flus by an average of four days.
Licorice root, used for centuries in Chinese medicine, is rich in dozens of plant compounds with antiviral and antimicrobial activities. Two compounds, glycyrrhizin (GL) and glycyrrhizic acid (GA), protect against herpes, HIV, hepatitis, coxsackie, enterovirus and SARS coronavirus. Other studies show licorice root significantly inhibits human respiratory virus and the flu.
Oregano oil, is a superconcentrated form of carvacrol, a powerful antiviral compound. In one study, oregano oil was effective in inhibiting five of eight viruses examined, including human respiratory virus and herpes simplex. It also has powerful antibacterial activities, especially against E. coli and other food-borne pathogens.