by Elizabeth A. Pector, M.D.

Bam! Pow! Zap!

They’re around every corner. They’ve even gotten to your friends. But the evil Dr. Flu and Mr. Cold are about to find out that it’ll take more than a few measly germs to get you down this fall.

Who wants a yellow sun, a magic lasso or Spidey sense when all you need is right inside your own body? Here are five super ways to boost your disease fighting powers.

1. EAT WELL.
This one may be simpler than you think. Pretty much all you have to do is eat right. 

“It’s along the lines of, ‘your chain is as strong as its weakest link,’” says Jill Weisenberger, M.S., R.D., nutrition counselor with the Hampton Roads Center for Clinical Research in Norfolk, Va. “If your diet is poor in just one area, you can suffer ill effects, including especially depressed immune function. Always, always focus on balance, with an emphasis on fruits and vegetables and whole foods versus processed foods.” Weisenberger, a regular contributor to James Hubbard’s My Family Doctor, also cautions that eating too much fat can hurt immunity.

But what about all those supplements purported to boost the immune system to help fight cold and flu? “This is one  [topic] with mixed study results,” says Weisenberger. Most studies do not show convincing benefits for many of these supplements. Even the old standbys vitamin C and echinacea may not help. And, despite popular belief, evidence is weak that vitamin C does anything to shorten a cold’s duration. (The National Center for Complementary and Alternative Medicine offers free information on some supplements.)

There is one caveat on this subject of supplements: A multivitamin may be helpful. Though a panel convened by the National Institutes of Health decided in 2006 that evidence wasn’t strong enough to recommend for or against healthy people taking multivitamins, may nutritionists do recommend them.

Finally, both overweight and underweight people are at greater risk of infections, and undernourished seniors are at particular risk. Fall is a wonderful time to treat yourself to delicious fresh fruits and vegetables. Your immune system will thank you for it! 

2. AVOID SECONDHAND SMOKE.
Stay away from smoke--on either end of the cigarette. In 2001, the well-respected Women’s Health Study found that though female smokers don’t get colds more often, their colds last longer (more than seven days, versus one to three for nonsmokers). Smokers also get the flu more often than nonsmokers and die of flu and pneumonia at a greater rate.

What's more, secondhand smoke increases the risk of colds and flu in adults and children. Each year, up to 300,000 lower-respiratory-tract infections (such as pneumonia and bronchitis) in children younger than 18 months can be blamed on smoke exposure.

“There is a lot of medical literature to support the evidence that moderate exercise does boost the immune system,” says fitness expert Rita Beckford, M.D., host of the fitness and weight-loss DVD Home With Dr. B and a member of James Hubbard’s My Family Doctor’s editorial board. A brisk walk or slow run for 30 to 60 minutes several times a week will likely do the trick.

You may have heard that intense exercise lowers your immune system. Very intense training or competition may, in fact, slightly lower resistance to colds in athletes who compete in marathons and other endurance events. But most of us don’t have to worry about that, and for those who do, the benefits of exercise (including the intense stuff) far outweigh the risk of getting a cold.