The Surprising Finding Every Diet Soda Drinker Should Know

If you have ears, you've probably heard that diet soda is bad for you. While it might seem relatively better for you than regular soda because it's lower in calories, the diet stuff is loaded with artificial sweeteners that worry medical experts concerned about the long-term effects of consuming these man-made ingredients found in reduced-calorie drinks and food.

Some studies suggest that certain artificial sweeteners can cause cancer, but because many are done on mice, not humans; infer associations from observational studies instead of clinical experiments; or test unrealistically large amounts of sweeteners, they're not sufficient proof to pull soda or straight-up artificial sweeteners off the shelves.

A series of new studies just published in Nature examined how these sweeteners affect your metabolic system: The results suggest that eating artificial sweeteners may lead to glucose intolerance, which is the first sign of type 2 diabetes and is associated with obesity and an increased risk of death. (In other words, you don't want it.)

The details: Scientists first fed mice water laced with FDA-approved amounts of common artificial sweeteners scaled down to mouse size. The mice developed glucose intolerance. Then researchers took gut bacteria of people who consumed artificial sweeteners and put it into sterile guts of mice. Those mice developed bacteria that's already known to increase the risk of diabetes and obesity in mice and humans, and the mice developed the same kind of glucose issues.

In a teeny human study conducted by the same researchers, seven volunteers who didn't normally drink artificially sweetened foods consumed 10 to 12 packets of artificial sweetener every day for a week. (A 12-ounce can of diet soda contains a little more than five packets, according to Cancer.org.) Even though the study was short and the exposure to chemical sweeteners was relatively brief, more than half of the people developed the gut bacteria related to glucose intolerance and showed signs of glucose intolerance in blood tests. Researchers think that because the body doesn't absorb artificial sweeteners, they encounter and affect more gut bacteria as they pass through your body. Ultimately, they trick your body into thinking you've overdosed on sugar, which compromises your body's ability to regulate sugar in the bloodstream and leads to metabolic disease that's potentially fatal.

It's no wonder that another part of this new research involving a sample of almost 400 people linked heavy consumption of artificial sweeteners to high blood sugar.

The bottom line: While the results seem to paint a pretty bleak picture for people who drink diet soda or eat artificially sweetened foods (like reduced-calorie yogurts and sugar-free sweets), experts still say the findings are inconclusive and that more research is definitively needed before you overhaul your diet.

That said, it probably wouldn't hurt to preemptively limit artificial sweeteners in your diet by switching from diet soda to water, or eating foods flavored with natural sweeteners, like agave, honey, or stevia, in moderation.