Copyright © 2009
by Daniel Matthew Korn

All Rights Reserved

Recent studies have demonstrated that soda consumption is a risk factor for weight gain. This does not surprise people, because conventional wisdom holds that sugar causes weight gain. Since most soda is filled with sugar, this theory would predict that soda would cause weight gain. However, what it would not predict is that diet soda, which contains almost no calories, would also cause weight gain. In fact, diet soda consumption is an even stronger predictor of weight gain than is consumption of regular soda. In an eight-year study of 1,550 Americans at the University of Texas Health Science Center, 622 started at a normal weight. About one-third of these 622 participants became obese or overweight over the course of the study, and the amount of soda they drank was a strong predictor of whether they would become overweight. Here are the percentages of the normal weight participants who became overweight or obese, according to their soda consumption:¹

To most people, the mystery here is why diet soda causes weight gain, while they readily accept that soda made with refined sugar causes weight gain. Remember, we have already seen that sugar in 100% fruit juice does not cause weight gain. People have been cultivating fruit and making fruit juices for thousands of years without obesity resulting. Of course, this study does not necessarily mean that soda causes weight gain. Perhaps people who eat fast food are more likely to drink soda, and something in fast food causes weight gain. This would explain why soda consumption seems to cause weight gain, but it would not explain why diet soda is about 36% more likely to be associated with weight gain than is regular soda.

We have to look at every theory no matter how improbable, so let us see if diet soda can be responsible for the increasing levels of obesity since the start of the twentieth century. The answer, of course, is a resounding “No,” because the first diet soda was introduced to the United States in the 1960s, long after the obesity epidemic was underway. This means that, even if diet soda has contributed to increased obesity, it does not explain the weight gain seen over the prior 60 years. Then there is the theory that artificial sweeteners, which became popular in the 1950s, cause weight gain, but this does not explain why regular soda causes weight gain. Why should sugar in regular soda cause weight gain when the sugar in 100% fruit juice does not?

  Last Chapter       Next Chapter 

Citations: