Part 3: Lifestyle and Immunity

exerciseIn the last two parts of this series, we addressed how nutrition and specific supplements can help boost your immune system and keep you healthy throughout the cold and flu season. In the third and final part of this series, we wanted to look at lifestyle and immunity. A healthy diet will only go so far if you don’t have these other lifestyle factors in place also.

Manage Stress

Being under too much stress is probably the first thing that lowers our ability to fight off disease. Many of us are under chronic-low grade stress the majority of the time. We have a lot of demands between work, family, and other day-to-day challenges. Although the relationship between stress and immunity in humans is complex, animal studies can give us many clues as to how our immune system reacts to stressful situations. When mice infected with the flu virus were placed in a stressful situation, the rate of the production of antibodies and other immune cells was reduced.

In human studies, it has been found that short-term stress like taking an exam doesn’t have as significant an effect on the immune system as chronic daily stress does.  Stress increases the presence of the hormones, cortisol and adrenalin, both of which suppress the immune system.

If you are under chronic stress, try to come up with a plan to help manage stress better. Laugh with some friends, take time off work, or unwind with a hot bath. Stress management should be a part of your daily life, especially to help keep your immune system healthy and strong.


The connection between exercise and immune function is complex. After very strenuous exertion like running a marathon, the immune function actually decreases for a short period of time (72 hours).  But, it has also been found that daily brisk walking (30-60 minutes) actually decreases the number of sick days overall.  It is believed that exercise helps remove bacteria from the lungs, reducing infections. Exercise also decreases stress, therefore it helps maintain a healthy immune system overall. The relationship between exercise and immunity is complex and more research is needed to determine exactly how exercise helps the immune system.


Adequate sleep is critical for optimal immune function. During sleep is the time when our immune system regenerates, creating new antibodies and immune cells to fight off illnesses during the day. It also helps decrease inflammation, reducing our risk of chronic diseases. Most adults need between 8-10 hours of restful sleep in a dark, cool room. However, many of us have a hard time getting that much with so many other demands on our time. If you have difficulty sleeping, make sure you go to bed and wake up at the same time every day. Start to unwind and relax about an hour before bed to tell your body it is time sleep. Turn off all cell phones, the television, and any other bright lights for restful sleep. You can also try some sleep boosting foods, like cherries, almonds, and decaf herbal tea.

Other Habits

Other lifestyle habits are also important for staying healthy. The first is to try to not put toxic substances into your body by drinking alcohol excessively or smoking. Both alcohol and smoking cause inflammation which weakens the immune system.

Be sure to wash your hands frequently during cold and flu season to prevent infection. Using an alcohol-based gel is just as effective if your hands are not visibly soiled.

If you maintain these lifestyle habits, along with the healthy diet and supplements discussed in parts 1 and 2, you will stay healthy all winter long!