Skip Artificial Sweeteners

Despite the hype, artificial sweeteners, marketed to help you live a low-sugar life or lose weight, may actually contribute to your weight problem.

People usually eat food containing artificial sweeteners (primarily aspartame, sucralose, stevia, and saccharin) to lose excess pounds or to keep their weight down. Unfortunately, studies show low- or no-calorie sweeteners often don’t help.

In fact, some research suggests non-nutritive sweeteners (NNS) may even cause weight increase in some people, and the additives may be linked to an increased risk of certain health problems.

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The not-so-sweet sweet side of artificial sweeteners

In a review of 56 studies of artificial sweeteners, published in BMJ,  a team of University of Freiburg researchers concluded there was no evidence that replacing sugar with no calorie sweeteners helped overweight or obese people lose weight.

Another deep dive into the impact of artificial sweeteners on weight, published in the Canadian Medical Association Journal, analyzed multiple studies involving the diets of several hundred thousand people and came up with some more bad news about non-nutritive sweeteners. The findings showed non-nutritive sweeteners had no significant effect on weight loss.

What’s more, consuming artificial sweeteners regularly was linked with weight gain — not loss — and increases in girth around the middle. In addition, higher incidences of obesity, hypertension, metabolic syndrome, type 2 diabetes, and heart problems were associated with diets that included artificial sweeteners, although the link can’t prove a direct cause and effect.

If you are pregnant or thinking about becoming pregnant, you might want to put down your diet drink. A study of 2,200 mothers and babies, published in the International Journal of Obesity, found moms who drank artificially sweetened beverages during pregnancy increased the odds their offspring would be obese at age three.

“Typically, we think of sugar as the ‘bad guy,’ but it turns out that replacing sugar with NNS may not be such a good idea,” said Meghan Azad, MD, an associate professor of health sciences at the University of Manitoba and a research scientist at the Children’s Hospital Research Institute of Manitoba.

“Our study found that children born to mothers reporting daily consumption of artificially sweetened beverages (diet pop or NNS added to coffee or tea) during pregnancy had significantly higher body mass index (BMI) at three years of age compared to children born to mothers who did not consume NNS beverages.”

Could artificial sweeteners hold health dangers?

Interest in how non-nutritive sweeteners may impact the body has grown in recent years. Mice studies first suggested that these sweeteners can actually promote weight gain. They may boost the bacteria in our gut, with the deceptively charming name of “Firmicutes,” that seem more likely to trigger fat storage — the same bacteria abundant in the guts of obese mice. In other words, even though the sweetener in a soda doesn’t have a big calorie count, it potentially makes the soda more fattening.

In one study, 10-week-old mice ate a daily dose of aspartame, sucralose, or saccharin. Another group of mice drank water laced with either glucose or sucrose, two forms of ordinary sugar. It turned out that after only 11 weeks, the mice on the artificial sweeteners were showing signs of high blood sugar, a precursor to diabetes.

In order to test whether a change in gut bacteria was linked to the problem, the researchers gave the mice broad-spectrum antibiotics that killed their gut bacteria temporarily. This brought the mice back to ground zero. The gut bacteria eventually returned to the pre-sweetener balance and blood sugar fell in the mice. Eran Segal of the Weizmann Institute of Science in Rehovot, Israel, and co-author of the study, was impressed enough by this result to give up using artificial sweetener in his morning coffee.

Mice studies don’t translate directly to predictions about humans: People are genetically diverse and have specific eating habits that vary in their lifetime. Mice are much less individual and complex.

How artificial sweeteners affect humans may vary. In one study, when seven lean volunteers who normally didn’t eat artificial sweeteners consumed saccharin over five days, three of them didn’t experience any change in their gut bacteria or blood sugar. Four of them wound up with more Firmicutes and higher blood sugar.

Should you give up artificial sweeteners?

The US Food and Drug Administration (FDA) documents whether non-nutritive sweeteners, like all other ingredients added to food in the U.S., are safe for consumption. For now, all the NNS additives used in the U.S. are deemed safe, with a few exceptions. For example, the FDA warns that people with a rare hereditary disease known as phenylketonuria (or PKU) have a difficult time metabolizing phenylalanine, a component of aspartame. That means consuming anything with aspartame could lead to serious health problems.

The “all clear” designation to other approved artificial sweeteners may change as more research is conducted into any possible health risks associated with the food additives.

For now, researcher Azad thinks the lack of proven benefits of NNS additives — and questions about whether artificial sweeteners do carry risks for weight gain and possible health problems — should at least cause you to consider not automatically choosing the sweeteners because you think they are healthier than sugar.

Instead, consider satisfying your sweet tooth with more. Opt for black coffee and give yourself time to get used to a non-sweet brew. A high-fiber diet rich in whole grains, beans, and vegetables will likely help with weight loss more than artificial sweeteners.

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