Are Diet Sodas Bad for You?

Featured Article, News and Advice, Nutrition, Weight Loss
on July 12, 2011
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What could be more refreshing than the bubbly, bitingly sweet taste of a cold glass of diet soda on a hot summer day? Just the thing for someone who wants to have their treat and stay trim, too. Or is it?

According to two studies presented recently at scientific meetings of the American Diabetes Association, diet sodas could actually have an effect exactly opposite of what we use them for. In one study of almost 500 people, researchers found that diet soda users saw 70 percent greater increases in waist circumference over time than those who didn’t drink the beverages. Those who drank two or more diet sodas a day experienced 500 percent greater increases!

Concern about our waist sizes go beyond mere vanity. Waist circumference is one measure of visceral fat, often called belly fat, which is linked to increased risk for type 2 diabetes, heart disease and some types of cancer. Indeed, the other study showed that diabetes-prone mice who were daily fed aspartame, a low-calorie sweetener found in diet sodas, had higher blood sugar levels than those who didn’t get the aspartame. 

Studies aside, however, we’ve long advised limiting the use of artificial sweeteners at Green Mountain at Fox Run, our healthy weight loss spa exclusively for women. Here’s why:

Artificial sweeteners can interfere with the appreciation of naturally sweet foods. When we drink diet soda or use artificial sweeteners in our coffee, tea or on other foods, we train our taste buds to prefer intensely sweet flavors. So a treat like a juicy fresh peach of summer just doesn’t measure up.

People seeking to manage their weight often use diet sodas and other no- or very-low-calorie foods to mask hunger. So they end up going too long without a needed meal or snack, which can set them up for out-of-control eating.  I wouldn’t doubt that this is one reason for the findings in the first study mentioned above.




So what do we encourage instead as a refreshing drink on a hot summer day—or for that matter, any day? Nothing quenches like good old water.If you need a flavor boost, try adding lemons, fresh mint or herbal teas. Or my new favorite: Slice lemons and cucumbers into a pitcher, add water and let it steep.

Love the bubbles? Stock up on seltzer, or make your own with a seltzer maker (like the SodaStream Home Soda Maker). Seltzer is just water that’s had carbon dioxide dissolved in it.  Flavor bottled or homemade seltzers with bits of fruit or splashes of fruit juice, if you’d like.

If you decide to continue using diet sodas, use them in moderation. And remember they aren’t a substitute for eating well.


Marsha Hudnall, RD, MS, CD, is a nationally known nutritionist with more than 25 years experience as a weight management specialist. She is the owner and program director of Green Mountain at Fox Run, a women’s weight loss program and spa retreat, that has helped thousands of women feel good about themselves now, regardless of their size, and in the process, helped them move towards healthier weights and lives. She serves on several boards and has authored seven books on health and healthy weight loss.