8 immune-boosting snacks under 75 calories.

You've heard the phrase "feed a cold." It turns out the opposite may be true: Moderately restricting calories can actually enhance immune-system activity. In one study, a group of men and women who were overweight (not obese) lowered their caloric intake by 10-30 percent for six months. At the end of that time, researchers found that those who followed the calorie-restricted diet had improved immune-system parameters, including increased T-cell proliferation, compared to a control group.

So are you ready to eat your way to a healthier winter? Ward off colds and flu with these low-cal, high-immunity foods that feed your immune system-not your cold.

1. Brazil nuts are one of the best food sources of selenium, a well-researched antioxidant that improves immune response. In one study, a daily Brazil nut was more effective than supplements in increasing blood selenium levels. Snack on: Two Brazil nuts chopped and sprinkled on a cup
of steamed broccoli florets.

2. Grapefruit contains hesperidin, an antioxidant that has been shown to repair damaged immune function and lower inflammation. Snack on: Half a grapefruit drizzled with raw, unfiltered honey.

3. Spinach is a low-calorie source of vitamin E, which is essential for immunity. Studies have shown that even a small vitamin E deficiency can impair the response of certain immune system functions. Snack on:
2 cups of chopped spinach tossed with balsamic vinegar and ¹/₄ cup sliced strawberries.

4. Oysters are the best food source of zinc. Many studies have shown that even a mild zinc deficiency suppresses immune function. Snack on: Three small oysters with a dash of inflammation-busting hot sauce.

5. Pumpkins are loaded with alpha-carotene and beta-carotene, which the body converts into immune-supportive vitamin A. Snack on: 1 cup steamed pumpkin, mixed with cinnamon and nutmeg and drizzled with raw, unfiltered honey.

6. Okra supports the body's production of glutathione, a powerful antioxidant that supports the immune system. Snack on: 1 cup of cooked okra drizzled with olive oil and sprinkled with (immune-boosting) turmeric.

7. Brussels sprouts are high in cysteine, an amino acid that lessens inflammation and promotes white blood cell activity. Snack on: 1 cup of thinly sliced Brussels sprouts sautéed in 1 teaspoon of olive oil and sprinkled with smoked paprika.

8. Oats contain beta-glucan, a type of fiber that enhances the ability of immune cells to move quickly
to infection sites and eliminate bacteria. Snack on: ¹/₂ cup cooked oatmeal, sweetened with stevia.