Breakfast: Unsweetened bran cereal with berries
Fiber is a nondigestible carbohydrate that feeds the good bacteria in your gut. And when the little buggers are happy, they help keep the immune system ready when needed. A half-cup of wheat bran has 12.5 grams of fiber, and by adding berries, you'll earn a few more. Plus, blueberries and other dark-colored berries are rich in flavonoids, antioxidants that improve the health of macrophages and other virus-eating cells.
A brisk walk
"Immune cells circulate the body during exercise and for two or three hours afterward,” says David Nieman, director of Appalachian State University's Human Performance Lab. Aim for 30 to 60 minutes of cycling, swimming, jogging or walking that's brisk enough to make you breathe hard.
Post-workout smoothie or salad
At the start of the pandemic, Helen Messier, a California-based family practitioner and immunologist, added a daily all-plant smoothie to her diet that included a number of different fruits and vegetables. You should, too. “Nutritionally, variety is the most important thing,” she says. “So I try to get in at least 10 servings of fruits and vegetables every day."