Immune system plays a key role for our health. Unfortunately, immune health can be compromised by some environmental and lifestyle factors. Some foods can help restore immune system, Fox News reports.

Chicken Soup

Besides soothing a sore throat or keeping you hydrated, chicken soups may keep your airways healthy, as well. Researchers have found that it deters movement of inflammatory white cells, which can help prevent colds by blocking the accumulation of cells in the bronchial tubes. The soup will be tastier if you add some garlic, carrots, onions or cilantro.

Broccoli

Broccoli is packed with immune-boosting nutrients like vitamins A, vitamin C, and glutathione antioxidant. The latter protects the body from free radicals by fortifying immune health and boosting antioxidant protection. It should be noted that in order to benefit from broccoli, it should be eaten raw, but if you’re not a fan of raw broccoli, try making a fresh broccoli salad with shredded cheese and other veggies.

Sardines

Fatty fish is rich in omega-3 fatty acids, which helps reduce the risk of heart disease and inflammation in the body. A new study shows that omega-3 fatty acids may also help boost the immune system by enhancing the functioning of immune cells. While salmon, tuna, and trout are all good sources of omega-3 fatty acids, sardines may trump their fishy counterparts. Sardines are not only high in omega-3 fatty acids, due to their small size they are extremely low in contaminants such as mercury

Yogurt

Regularly eating “good bacteria” (or probiotics) can help improve digestion and strengthen your immune system. A daily yogurt (7 ounces) is as effective in promoting immunity as taking pills. Yogurt and other dairy foods are also fortified with vitamin D, which decreases the risk of flu and colds. But stay away from yogurts with added sugars and artificial sweeteners. Instead, choose a plain yogurt and add your own natural sweetness like fresh berries, dried fruit or a touch of honey.

Mushrooms

Mushrooms also help to promote immune system. They are rich in selenium, B vitamins, and antioxidants. Researches show that mushrooms increase the production and activity of white blood cells, which is important for struggling against infections.

Tea

Both green and black tea is useful for our immune system. They provide disease-fighting antioxidants (polyphenols and flavonoids) that protect against free radicals and help destroy them. Researches show that people who drank 5 cups a day of black tea for two weeks had 10 times more virus-fighting interferon in their blood than other who drank a placebo hot drink.