De-stress. Whether your stress is physical, emotional, or mental, it’s a major drain on immune power. To avoid coming down with a cold or the flu this winter, incorporate stress management into your daily routine. De-stress with yoga, tai chi, moderate exercise, or writing in a daily journal. Meditation is a great tool for calming the nerves on a stressful day. Visualization can also help your immune system perform at its best; just spend a few minutes a day imagining a vital and effective immune system.

Socialize. Friendships and other relationships are also linked to immune function. In fact, people who are involved in social activities and who laugh a lot are less likely to catch colds (Journal of the American Medical Association, 1997, vol. 278, no. 15).

Exercise. Regular, moderate exercise primes the immune system to be efficient and effective. But exercise can be too much of a good thing. Prolonged and intense training, such as running marathons, is taxing to many parts of the body, including the immune system. Immunity can be impaired for several days after strenuous exercise (Allergie Et Immunologie, 2003, vol. 35, no. 2), so take extra care of yourself after intense workouts.

Eat right. According to Heather Zwickey, PhD, director of research at the National College of Naturopathic Medicine in Portland, Oregon, certain foods, including caffeine and white flour, may promote inflammation in the body and worsen autoimmune diseases and should therefore be avoided. Saturated fats found in animal-based foods or the trans fatty acids found in many processed foods are also potential aggravators of autoimmune disease. Instead, choose wholesome fats, such as omega-3 fatty acids found in cold-water fish and some vegetable oils, such as flaxseed oil. These healthy fats help the immune system’s cells function more efficiently to detect and prevent germ attacks.

—V.D.T.