Q. Should I get a flu shot?

A. If you are in a high-risk group for the flu—small children, the elderly, and those with weakened immune systems—getting an annual flu shot may help protect you from becoming sick. But if you are generally healthy, you may want to take a more natural approach.

The flu vaccine traditionally contains two or three inactive or “dead” flu virus strains that were prevalent the year before. Because these strains are constantly changing, medical science is always playing catch-up, hoping that last year’s strains match those in circulation this year. If they are a match, the vaccine can prevent 70 percent to 90 percent of flu cases in people younger than 65. But there are no guarantees. The winter 2003 vaccine missed the mark for preventing the most prevalent strain of influenza.

Even if the vaccine is successful, there are risks. If you’re allergic to eggs, you should be aware that the flu vaccine contains egg protein, and thus getting a flu shot could cause a drop in blood pressure, wheezing, breathing difficulty, and hives in people with this allergy. Your flu shot may also contain a combination of additives, including thimerosal, a mercury derivative that can cause allergic reactions and, according to some experts, such as the Virginia-based National Vaccine Information Center, may be linked to autism in children. Many childhood vaccines no longer have thimerosal, but to remove any doubt, U.S. Reps. Dave Weldon, MD (R-Fla.), and Carolyn Maloney (D-N.Y.) have introduced legislation that would remove mercury-based preservatives from all childhood vaccines.

Some studies also show a connection between the flu vaccine and serious neurological side effects, particularly Guillain-Barre Syndrome (GBS). GBS is a disorder in which the body’s immune system attacks part of the peripheral nervous system. Symptoms include varying degrees of weakness or tingling sensations in the legs. In many instances, the weakness and abnormal sensations spread to the arms and upper body, eventually resulting in paralysis. Although the Centers for Disease Control and Prevention in Atlanta maintains that the risk of developing GBS is small (1 in 100,000), that wasn’t the case in 1976. Of the 46 million people vaccinated against swine flu, a type of the virus normally seen only in pigs, 532 developed GBS and 32 of those died that year. Still, more than 28 years have passed since then, and no other major outbreaks of GBS have occurred.

Unless you are at high risk for the flu, it’s relatively easy to guard against becoming ill. Along with eating a healthy diet, getting enough sleep, and exercising, you can find effective, natural ways to ward off the flu this winter.

This Ask the Expert is written by Kim Erickson, an herbalist, beauty and health writer, and book author based in Las Vegas.