Courtesy trayThis is wonderful news! Not for you, obviously, but it is for me. You see, I don't drink diet soda, and I love to shame people for their diet choices, so this news is just perfect for me:
Shame on you. Shame on you for drinking diet soda, shame on you for believing so foolishly that it would be part of a healthy diet plan, and shame on you for even trying to control your weight.
Why don't you just drink cool spring water, seasoned with a sprig of mint and a squeeze of lemon, like I do? That's nature's soda. Or are you too good for nature? No, you're not. Nature is too good for you. You know how I know? Because you drink diet soda, you shameful little shame shame.
It was good to get that out of the way. Didn't it feel nice? For me, I mean? It did.
As far as the research goes, it's one of those things where, despite the black and white, "Diet soda makes you fat" headlines (which I pretty much used here), the actual link between consuming pop with artificial sweeteners and human weight gain is pretty unclear. Researchers followed 474 subjects for ten years, and found that the people who consumed diet soda gained significantly more belly fat than those who did not drink diet soda. (The drinkers' waistlines grew about five times more than the non-drinkers' waistlines did.)
10 years seems like a decent length for the study, although I'm not sure if 474 is a very large number of participants. The main thing, however, is that this study doesn't show any actual mechanism behind the extra weight gain of diet soda drinkers. While there could be something in the artificial sweeteners themselves that encourages weight gain, it's also likely that the link is based more in behavior/psychology. Diet soda-drinkers could be substituting extra calories from other sources, because they avoided them in the soda. Or maybe they exercise less. Or perhaps they crave other sweet things, because of the sweetness of the soda.
As far as I can tell, too, the study compared diet soda drinkers to people who don't drink diet soda, not to people who drink soda sweetened with sugar or corn syrup, so it's not necessarily stating that diet sodas are a less healthy alternative to regular pop.
It could be that there's a causal link (that is to say, that artificial sweeteners are directly responsible for weight gain, as opposed to simply being associated with other behavior that causes weight gain). Artificial sweeteners do seem to have physiological effects on us, altering insulin secretion, gut pH, and appetite, and mice exposed to the artificial sweetener aspartame for three months were found to have higher blood sugar levels. But that doesn't mean that the diet sodas are for sure responsible for the weight gain in this study's participants. So, for now, take the research seriously to the extent that helps you be more conscious about the things you eat and drink I guess.
That's not the important thing, though. The important thing, of course, is that the study provides you with something to worry and feel bad about, and me with something to dangle over your head as I encourage those feelings in you.