Crucial Ways You Can Support a Healthy Immune System

Exercise, Sleep, Stress Reduction, and a Healthy Diet Play Important Roles in Protecting Health

If only there were a pill that could keep the immune system in top shape. You could take the pill every day and feel more protected against viruses, infectious bacteria, and other bugs that threaten health. It would be a simple and easy solution.


Too bad the only "pill" we have to maintain robust immune health is one that many people find hard to swallow. It's not a vitamin or an herb -- the evidence that those things ramp up protection just isn't there. Instead, it's a combination of healthy lifestyle habits.


While we don't have evidence that maintaining a healthy lifestyle will suddenly boost the immune system, we do know good habits contribute to overall health, supporting our ability to fight germs instead of creating new problems. And living a healthier lifestyle is something simple you can start right now.


One of the best ways to optimize your immune system is to get a good night's sleep. "Research has demonstrated that people who get less than six hours of sleep per night are about four times more likely to catch a cold compared with those who sleep seven hours or more," says Dr. Beth Frates, who directs wellness programming for the Stroke Research and Recovery Institute at Harvard-affiliated Spaulding Rehabilitation Hospital.


Why is sleep so important? "Sleep activates the immune system, which fights infections and scans for cancers or other signs of illness. Sleep deprivation depresses the immune system," explains Dr. Lawrence Epstein, a sleep expert at Harvard-affiliated Brigham and Women's Hospital.


Try going to sleep 30 minutes earlier, maintaining the same sleep and wake schedule every day, and shooting for seven to nine hours each night. Avoiding caffeine past 4 p.m. and avoiding alcohol or food a few hours before bedtime can lead to more restorative sleep.


Exercising regularly is another key to supporting your immune system. Exercise reduces blood pressure, cholesterol, and the risk of heart disease, diabetes, depression, and more. Exercise also improves blood flow to the brain, thinking skills, bone strength, and the body's "feel good" chemicals.


The goal is to get at least 150 minutes per week of moderate-intensity activity, like brisk walking. "But any amount of exercise that gets your heart and lungs working overtime will help, even just a few minutes per day. If you're stuck inside, you can walk around, dance to music, or step or jump in place while you're watching TV or talking on the phone," suggests Dr. Suzanne Salamon, associate chief of gerontology at Harvard-affiliated Beth Israel Deaconess Medical Center.


Chronic stress has many negative effects on health, and a suppressed immune system appears to be one of them. This could be because of the chemicals, such as cortisol, that the body releases in the "fight or flight" mode. "High cortisol levels lower the immune response, specifically inhibiting white blood cells called lymphocytes, which help you fight infection," Dr. Frates says.


She advises practicing deep breathing as a way to lower your stress and your cortisol levels.


"Deep breathing helps to stop the fight-or-flight response and allows the opposite 'rest and digest' response to take over and create a sense of calm," she notes.



Good nutrition plays an important role in maintaining a healthy immune system. For example: "Fiber will positively affect the gut microbes that aid immunity. Nutrients from fruit and vegetables provide vitamins, minerals, and antioxidants that also support immune function," says Debbie Krivitsky, a registered dietitian at Harvard-affiliated Massachusetts General Hospital. "Vary the colors of fruit and vegetables so that you include many different antioxidants that are protective against disease."


In addition to eating lots of fruit and vegetables, you should eat a diet rich in legumes, whole grains, fish, nuts, and seeds, Krivitsky advises.


Other steps to support your immune system: Stay up to date with immunizations, don't smoke, drink alcohol only in moderation, maintain a healthy weight, and try to get underlying health conditions under control. The sum total will be better overall health and a better chance of protecting it.