Recent studies have shown that eating too much sugar can cause obesity, liver problems, and diabetes. As a result, many people grab for a zero-calorie soda instead of a normal one, in the name of health. However, a new study has shown that artificial sweeteners can cause just as many problems as plain old sugar.

“Despite the addition of these non-caloric artificial sweeteners to our everyday diets, there has still been a drastic rise in obesity and diabetes,” said lead researcher Brian Hoffmann, PhD, assistant professor in the department of biomedical engineering at the Medical College of Wisconsin and Marquette University. “In our studies, both sugar and artificial sweeteners seem to exhibit negative effects linked to obesity and diabetes, albeit through very different mechanisms from each other.”

Artificial sweeteners are often added to food, especially in diet and low-sugar products. Previous studies have not been able to definitively connect them to negative health consequences. To fill this knowledge gap, researchers tracked the effects of sugar and artificial sweeteners (aspartame and acesulfame potassium) on rats and cell cultures. They looked at the biochemical changes that went on in the rats’ bodies with unbiased high-throughput metabolomics. They also looked at the lining of blood vessels to keep tabs on vascular health.

A popular zero calorie sweetener. Image credits: Raysonho @ Open Grid Scheduler / Grid Engine.

“After analyzing the metabolites in the plasma, we found that glucose did not exhibit many significant changes in metabolites versus the rats on control diet, which we hypothesize was due to the shorter duration of the study or we could increase the dosing of glucose (these studies are underway). Another sugar, fructose, did significantly alter metabolism in this rat model, including lipid (fat) metabolism. In this same study, we saw that aspartame and acesulfame potassium altered energy and lipid metabolism negatively. Acesulfame potassium is also metabolically stable (not degraded) and is absorbed into the bloodstream and excreted through the urine,” said Hoffmann to ZME Science.

After three weeks of feeding the rats either the glucose/fructose or artificial sweetener rich diet, the amount of biochemicals, fats, and amino acids in their blood differed. Artificial sweeteners changed fat and energy metabolism. In particular, acesulfame potassium accumulated in the blood and harmed blood vessel lining cells. When tested on vascular endothelial cells, the researchers observed that it inhibited homeostatic signalling pathways, which can damage the cardiovascular system, as Hoffman informed ZME Science.

Zero calorie soda. Image credits: Mike Mozart.

“Additionally, it is important to note that all sugars and sweeteners are not created equal. They have different chemical makeups and thus mechanisms of action so it will be important not to generalize them all in one category but test specific mechanisms of action for each. For instance, our results have shown the acesulfame potassium has a greater effect on metabolic changes than aspartame and it builds up in the bloodstream, which could be very detrimental,” said Hoffmann to ZME Science.

It is not possible to say from the study whether sugar or artificial sweeteners are worse for you in the long run. The key to being healthy is to cut down on sweeteners in general, because the body can only process so much. The daily recommended allowance is 25 g a day, though the average person eats almost five times that amount. It is important to recognize the not-so-obvious places in our diets where sugar lurks, such as in drinks, yogurts, and pasta sauces. Instead of taking a zero-calorie product, choose something naturally low in sugar.

The lead researcher, Hoffmann, presented the research at the American Physiological Society annual meeting during the 2018 Experimental Biology meeting on April 22 in San Diego.