9. Get vaccinated
Though the effectiveness of the annual flu shot varies, it’s still one of the best defenses we’ve got, says Dr. Plourde. Some fear that because the flu vaccine contains several influenza strains in one shot, it can actually tax the immune system—but don’t worry. “Your immune system has a phenomenal capacity,” he says. It is estimated that in the United States, each year on average 5 to 20 percent of the population gets the flu and more than 200,000 people are hospitalized from seasonal flu-related complications. The shot’s benefits, says Dr. Plourde, far outweigh the risks.