Feeding your body certain foods may help keep your immune system strong.

If you’re looking for ways to prevent colds, the flu, and other infections, your first step should be a visit to your local grocery store. Plan your meals to include these 15 powerful immune system boosters. 1. Citrus fruits. Most people turn straight to vitamin C after they’ve caught a cold. That’s because it helps build up your immune system.

Vitamin C is thought to increase the production of white blood cells, which are key to fighting infections.

Almost all citrus fruits are high in vitamin C. With such a variety to choose from, it’s easy to add a squeeze of this vitamin to any meal.

Popular citrus fruits include:

grapefruit
oranges
clementines
tangerines
lemons
limes
Because your body doesn’t produce or store it, you need daily vitamin C for continued health. The recommended daily amountTrusted Source for most adults is:

75 mg for women
90 mg for men
If you opt for supplements, avoid taking more than 2,000 milligrams (mg) a day.

Also keep in mind that while vitamin C might help you recover from a cold quicker, there’s no evidence yet that it’s effective against the new coronavirus, SARS-CoV-2. 2. Red bell peppers If you think citrus fruits have the most vitamin C of any fruit or vegetable, think again. Ounce for ounce, red bell peppers contain almost 3 times as much vitamin C (127 mgTrusted Source) as a Florida orange (45 mgTrusted Source). They’re also a rich source of beta carotene.

Besides boosting your immune system, vitamin C may help you maintain healthy skin. Beta carotene, which your body converts into vitamin A, helps keep your eyes and skin healthy. 3. Broccoli. Broccoli is supercharged with vitamins and minerals. Packed with vitamins A, C, and E, as well as fiber and many other antioxidants, broccoli is one of the healthiest vegetables you can put on your plate.

The key to keeping its power intact is to cook it as little as possible — or better yet, not at all. ResearchTrusted Source has shown that steaming is the best way to keep more nutrients in the food.