Obesity Reduces Effectiveness Of Flu Shots

Overweight and obese people are more likely that healthy weight people to experience flu illness after receiving a flu shot, new U.S. research has found. Scientists had earlier found that obesity impairs the ability of the human immune system to fight the influenza virus. This study found that obesity actually reduces the effectiveness of the annual flu shot: influenza vaccine antibody levels declined much faster in obese people compared to healthy weight individuals. They also found that responses of white blood cells that play a key role in the body's immune system were defective in heavier people. Approximately half of obese participants in the study had a four-fold drop in antibody levels 12 months after the shot, compared to only a quarter of healthy weight participants.