While the influenza vaccine has never been 100 percent perfect at preventing the flu, according to two new studies, the flu shot may not be quite as effective as doctors previously thought, especially for certain populations such as obese people.
A study published in The Lancet found in a review of 31 published studies that trivalent inactivated vaccine — the most widely used influenza vaccine in the United States — is about 60 percent effective in healthy adults. That particular vaccine accounts for about 90 percent of flu shots in America and was once thought to be about 70 percent effective.
Another study found that the influenza vaccine may not be as effective for those who are obese. Published in the International Journal of Obesity, researchers found that obesity was associated with an impaired immune response to the influenza vaccination in humans, thereby making obese people more susceptible to the flu.
Jennipher Walters is the CEO and co-founder of the healthy living websites FitBottomedGirls.com and FitBottomedMamas.com. A certified personal trainer, lifestyle and weight management coach and group exercise instructor, she also holds an MA in health journalism and regularly writes about all things fitness and wellness for various online publications.