Chicken soup was a staple of your mom’s diet when you were sick. Your doctor will always urge you to eat more vegetables. How much can a healthy diet help to keep your immunity up?

Experts say quite a lot. Seema Bonney is an emergency physician who also founded the Anti-Aging & The Longevity Center of Philadelphia.

According to her, the diet has a significant impact on the risk of developing diseases. Poor dietary habits are responsible for as high as 30% of all cancers, according to Anna Taylor, a Cleveland Clinic clinical dietitian and lead outpatient clinical dietian. Certain foods can help you prevent upper-respiratory infections, and keep your gut microbiome healthy.

While there is no food that can prevent COVID-19 (the common cold and flu), a diet high in vitamins can help your body prepare for any eventuality. This is particularly important as you age. Bonney says that as we age our immune response decreases so it is important to see every meal as an opportunity for nourishment and support of a healthy immune system.

These superfoods will help boost your immune system.

Superfood No 1: Yogurt

There are many benefits to maintaining a healthy gut microbiome. This is a way to regulate your immune system. Probiotics may have a slight effect on the common cold, according to research. Taylor states that probiotics have a modest effect on common cold reduction. “Eating foods high in probiotics every day supports a healthy stomach, supporting the microbiome, which is where most of the immune system is located,” Taylor said. Yogurt can be a great way to give your gut live cultures.

Plain yogurt is a great way to start your day. You can also add it to smoothies or oatmeal for a creamier taste. Taylor recommends that you avoid yogurts with added sugars. Instead, choose the Greek yogurt which Taylor claims has twice the protein as regular yogurt.

Probiotics can also be found in foods like kimchi and kefir, sauerkraut, pickles, and kombucha. Michele Renee, director for integrative medicine at Northwestern Health Sciences University, says that pickles made with salty waters are better than those made with vinegar.

Superfood No. 2: Garlic

Prebiotics are food for the good bacteria living in your gut. These non-digestible compounds, which are often fiber-rich foods, get metabolized by the gut microorganisms. They help to maintain a healthy gut flora. John Whyte (author of Take Control of Your Cancer Risk) and chief medical officer at WebMD, says that probiotics are live cultures. However, prebiotics allow the good bacteria to thrive. He says that probiotics do not have to be taken, but prebiotics could help them work better. Garlic is one of these powerful forms of prebiotics.

Garlic has immune-boosting properties that can help your gut thrive. William Li, a doctor and author of Eat to Beat Disease. The new science of how your body can heal itself says that garlic contains allicin, a bioactive called. University of Florida researchers found that taking aged garlic extract supplements can significantly lower the symptoms of flu and cold symptoms.

Other forms of prebiotics include fiber rich foods like whole grains, onions and bananas as well as ginger, asparagus, and garlic. Research has shown that ginger can help with nausea due to a variety of causes.

Superfood No. 3: Blueberries

Blueberries are a superfood because of anthocyanin, a flavonoid that they contain. It has multiple immune-boosting properties. Li said that a study by Vanderbilt University (Appalachian State University), Montana Woman’s University, Texas Woman’s University, and Vanderbilt University showed that eating blueberries almost doubles the number of immune natural killer cell in the bloodstream. Additional research has shown that the antiviral properties of blueberries’ flavonoids may reduce the risk of upper respiratory tract infections.

Berries are rich in antioxidants which can fight against free radicals that cause aging. Whyte recommends that berries with darker colors, such as blueberries and blackberries, be prioritized because they are more antioxidant-packed.

Superfood No 4: Kiwi

Oranges are high in vitamin C. But there are other fruits that are just as rich. Lon Ben-Asher is a registered dietitian at Pritikin Longevity Center and Spa and licensed dietary nutritionist. One medium kiwi provides 71 percent of the recommended daily intake.

Kiwifruit is rich in vitamin E, folate and carotenoids, as well as polyphenols. A small study with seniors living in the community found that eating four kiwis per day over four weeks did not reduce the incidence of upper respiratory tract infections. However, it significantly reduced the severity and length of head congestion. Participants also felt faster relief from sore throats.

You might also be surprised to learn that tomatoes, parsley, bell peppers and broccoli all contain high amounts of vitamin C. Ben-Asher suggests that you add parsley and thyme to your soups, or to salad dressings.

Superfood No. 5: Mushrooms

You might want to add mushrooms to your regular menu if you only enjoy them as toppings on pizza. These often overlooked fungi have a soluble fiber called Beta-Glucan. This can help stimulate your immune system to protect against fungal and bacterial infections as well as viruses. Li points out that white button mushrooms, as well as salivary IgA, can increase the protective immune antibodies. This was confirmed by a University of Western Sydney study. Oats and barley are two other foods high in beta-glucan.

Researchers at UCLA and the University of California at San Diego (UCSD), are conducting a clinical trial to see if mushrooms can boost immunity. Gordon Saxe, a doctor who heads the Krupp Center for Integrative Research (UCSD) and the study’s principal investigator, says that vaccines may work better if certain mushrooms are taken at the time of vaccination.

Superfood No. 6: Salmon

Omega-3 fatty acids have been a hallmark of fish, and some studies show that they are linked to improved cardiovascular health. However, salmon and other fatty fish are rich in vitamin D. Taylor points out that low levels of vitamin D are associated with higher incidences of upper respiratory infection.

Vitamin D can also be obtained from eggs yolks, tuna, cheese and egg yolks.

Superfood No 7: Beans & Lentils

Blue zones are the regions where people live longest. It turns out that beans are a staple food in the diets of centenarians who live in these areas. Other research shows that there has been a decline in mortality when people eat just a tablespoon of fiber-rich beans or lentils daily.

Experts believe that the zinc found in these legumes could be part of their strength, as the mineral boosts the production of white blood cell, which protects the body from microbial invaders. Immune dysfunction is also linked to a deficiency of the nutrient. Taylor states that research suggests zinc supplementation can reduce the severity and length of cold symptoms, if it is started early. Other sources of zinc include lean beef and fortified breakfast cereals, pumpkin seeds, and seafood like raw oysters.

Superfood No. 8: Tea

Relaxing on the couch with a cup of warm tea is a great way for you to unwind. You may be able to prevent infections by drinking tea. A study showed that drinking five to six cups of coffee a day increased immune activity. However, this did not happen in the coffee drinkers in the study. Other research has shown that coffee consumption can reduce ailments such as Parkinson’s disease and type 2 diabetes.

You can also add honey to your mug. Honey’s antimicrobial properties could help to reduce the symptoms of common cold and flu. A study concluded that honey is more effective at relieving nighttime coughs in children than cough suppressing drugs such as dextromethorphan and antihistamine diphenhydramines.