The flu is nothing to sneeze at, particularly if you’re “of a certain age.” Seniors age 65 and older account for 90 percent of the deaths from the flu each year, according to the Centers for Disease Control and Prevention. That’s why the agency recommends that older adults and anyone who has an immune system that is suppressed by medication receive an annual flu shot.    

But not everyone gets equal protection from the shot. Vaccines work by giving the immune system a sneak preview of incoming germs so infection-fighting cells can respond more quickly when the real threat strikes. As we age, immune cells lose their ability to “remember” vaccines, making them less effective. In fact, new studies show that the influenza vaccine is only 30 to 50 percent as effective in the elderly as it is in younger adults.

Until better vaccines are available, however, don’t skip your shot. “Thirty percent protection is still better than zero percent,” says Lone Simonsen, PhD, a professor of global health at George Washington University in Washington, D.C.

To get the most out of your shot – elderly or not – try these proven strategies to improve immune response.

Reduce stress  
Why:
Even modest stress reduces the body’s response to vaccines. The worst kind of stress is bereavement, which lowered the effectiveness of the flu vaccine by 70 percent, according to a 2006 study published in the journal Brain, Behavior and Immunity.
What to try: Grief counseling may help you stay healthy if you’ve recently lost a loved one, says study author Anna C. Phillips, PhD, of the University of Birmingham in the United Kingdom.  

Exercise
Why: Staying active keeps your immune system young.
What to try: Working up a sweat for twenty minutes three times a week can boost your response, says Marian L. Kohut, PhD, at Iowa State University. If you need to take it slower, a separate study from the University of Illinois in Champaign found that seniors who practiced 20 weeks of tai chi, a combination of meditation and movement, had a greater immune response than those who got the flu shot but didn’t practice tai chi.

Improve your diet
Why:
Good nutrition, including a diet high in antioxidants, can erase the effects of age on the immune system.
What to try: Eat plenty of fruits and vegetables in your daily diet. A study published in the Journal of Gerontology in 2002 found that seniors who drank a nutritional supplement with extra antioxidants for five months prior to their flu shot had only a small decline in immune function compared to a control group of healthy younger adults.

Get up early, if you’re a man
Why:
Hormonal fluctuations through the day may affect how well men respond.
What to try: A 2008 study published in the journal Psycho-physiology found that men who got their vaccines before 11 a.m. made twice as many antibodies to the flu as men who were vaccinated in the afternoon. Time of day seemed to make no difference for women.