Do Artificial Sweeteners Really Cause Weight Gain?

Once again, artificial sweeteners dominated the medical news this week.  This time it was from a study suggesting that artificial sweeteners might cause weight gain and heart disease.  In this article, I'll dissect the latest research and offer a practical approach to artificial sweeteners.

The Latest Artificial Sweetener Study

I really liked the quality of this latest study.  The researchers did a great job of trying to make sense of every study that has ever been published about artificial sweeteners.

While most health conscientious people consider artificial sweeteners as harmful, the health food industry has gravitated to stevia as a "healthy" alternative.  Fortunately, this study also included stevia.

To make sense of every credible artificial sweetener study that has ever been published, researchers divided these studies into two groups.  The first group consisted of randomized controlled trials or RCTs.

RCTs are considered the very most accurate type of a medical study you can do.  In RCTs, researchers randomly divide the participants into two groups.  This way, you can minimize confounding factors that might give you the wrong results.  In this study, researchers included 7 RCTs involving a total of 1,003 people who were then followed closely for an average of six months.

In contrast, this study also reported the results of 30 observational studies involving 405,907 people who were followed for an average of 10 years.  While these observational studies aren't very accurate, they can raise questions about the long-term safety of artificial sweeteners.

What Do RCTs Tell Us About Artificial Sweeteners

From the 1,003 people included from seven randomized controlled trials (RCTs), this study reported that when it comes to weight gain, artificial sweeteners are neutral.  In other words, they don't cause people to gain or lose weight.

Interestingly, when you look at all the studies published from the artificial sweetener companies, these studies almost always show that people lose weight.  However, when you look at studies that are not sponsored by artificial sweetener companies, there generally is no weight loss from artificial sweeteners.

Thus, if you can't give up your daily Diet Coke habit, then you can hold fast to the results from RCTs.  At least when you look at the health effects of artificial sweeteners out to six months, they don't appear to cause weight gain.

However, because RCTs are very costly to do, follow up periods tend to be very short.  Thus, with this average follow up of just six months, it is impossible to know if artificial sweeteners put you at risk for other diseases, like diabetes or heart disease.

As you know, most people don't just drink Diet Coke for six months.  Rather, they tend to drink it over a lifetime.  This is where the less accurate but long-term observational studies can be helpful.

What Do Observational Studies Tell Us About Artificial Sweeteners?

While artificial sweeteners, including stevia, looked relatively harmless in the six month long randomized controlled trials (RCTs), the results were quite frightening when you look at the 10 year observational studies.  Indeed, the 30 observational studies involving 405,907 people paint a completely different picture of artificial sweeteners.

The observational studies clearly linked artificial sweeteners to weight gain over time. Not only do these studies report weight gain but they also show that artificial sweeteners may increase your risk of diabetes by 30%!

If diabetes wasn't frightening enough, these observational studies also report a 13% increased risk of high blood pressure, a 26% increased risk of a stroke, and a 32% increased risk of heart disease!  Clearly,