Can Artificial Sweeteners Harm Your Health?

Q. I hear artificial sweeteners can cause mild to serious side effects ranging from headaches to cancer. Is this true?

A. Food-safety experts generally agree that there is no convincing evidence of cause-and-effect relationships between these sweeteners and negative health effects in humans, says Mike Herndon, a U.S. Food and Drug Administration spokesperson.

But what about anecdotal complaints from consumers, such as those who say aspartame gives them headaches? "There are likely genetic differences in our bodies' ability to break down artificial sweeteners," says researcher Linda McCauley, Ph.D., R.N., at the University of Pennsylvania in Philadelphia. "What bothers a few people may cause no issues for the majority."

Others fear the sweeteners could be fueling the obesity epidemic by increasing appetite. However, researchers lack the long-term studies needed to determine if this concern is valid. Most experts believe low-calorie sweeteners can be a helpful part of a reduced-calorie diet.