Carbonated soft drinks account for 7% of a typical American diet. It’s more like 13% for teens. So, it should be logical that we can cut our calories by 7% by switching to diet soda. The excess weight should just melt off, right?

It turns out, no. Regular drinkers of diet soda often gain more weight! There are two reasons for this. First, the diet soda drinker can rationalize away eating more calories: I have a diet soda so I can have a candy bar or an order of fries (or both). The second reason relates to the fact that when we consume something sweet, our bodies expect lots of calories to go with it. “When the body is fooled by tasting an artificially sweetened food, a craving for high calorie food can result.”

It gets worse. Artifical sweetners appear to actually reduce the metabolic response to high calorie meals. Yes, that’s right, artificial sweetners may well suppress your metabolism. No matter what WebMD says, this is a serious reason to consider losing the artificial sweeteners in your life.

Of course, it’s OK to have something sugary, fatty, or otherwise decadent now and then — as long as it really is only occasionally, you keep portion sizes small, and you only consume things that are really “worth it”. But if things are starting to plateau on your weight loss or fitness plan, it might be time to consider eliminating the artificial sweeteners and just accept that cheating is cheating and do it the old fashioned way.