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One Major Effect of Drinking Diet Soda Every Day, Says Science

Avoid sipping on this sugar-free alternative daily to dodge one of these side effects.
FACT CHECKED BY Olivia Tarantino
pouring coke soda into glass

In many ways, diet soda is a healthier alternative to its sugar-filled counterpart. It's lower in added sugar and calories, both of which contribute to obesity and chronic health issues like type 2 diabetes and heart disease. However, it's still not the perfect solution. In fact, you may be better off just choosing a low-sugar soda alternative over one that's completely sugar-free.

Here's why: one of the most popular diet sodas out there, Diet Coke, uses an alternative sweetener called aspartame. The artificial sweetener has been under fire since its debut in the 1980s for its potential cancer-causing effects. While the American Cancer Society states that research around those effects is inconclusive, there may be another reason to be skeptical of the alternative sugar. (Related: 15 Underrated Weight Loss Tips That Actually Work).

According to a 2008 study published in The Canadian Journal of Gastroenterology, people who drank aspartame-sweetened Diet Coke were more likely to experience moderate to severe fatty infiltration in their livers than those who drank non-diet sodas, including Sprite and Fanta. Why is this an issue? This infiltration can lead to a condition called, nonalcoholic fatty liver disease (NAFLD) where fat builds up in the liver and causes cirrhosis, otherwise known as late-stage liver scarring. Cirrhosis can eventually lead to liver failure if not addressed early on.

There are other known health issues associated with the artificial sweetener typically found in diet soda. A 2017 Nutrition Reviews special article that reviewed nearly two decades worth of data on aspartame concluded that consuming aspartame in quantities even within recommended safe levels may "disrupt the oxidant/antioxidant balance, induce oxidative stress, and damage cell membrane integrity, potentially affecting a variety of cells and tissues and causing the deregulation of cellular function, ultimately leading to systemic inflammation."

Another reason not to reach for diet soda daily? One study suggests drinking just one of the artificially sweetened beverages daily was linked to an 8% higher risk of type 2 diabetes; however, the meta-analysis looked at observational studies, which can only show correlation, not causation. And another study indicated that consumption of artificially sweetened drinks was associated with a 21% percent higher risk of developing the condition in older women (again, the study showed a correlation, not causation).

At the end of the day, there is research that supports both sides of the argument on whether or diet soda is harmless or harmful for your body. Our advice? Cut down on your intake to play it safe. If you can't shake the craving, consider limiting yourself to three servings of diet soda a week and then try, eventually try to drop it down to just one serving a week.

For more, be sure to read 29 Most Popular Diet Sodas—Ranked!

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Cheyenne Buckingham
Cheyenne Buckingham is the news editor of Read more
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