Artificial sweeteners may actually help reduce blood sugar levels instead of making you hungry

Artificial sweeteners like aspartame or saccharin have been previously reported to increase feelings of hunger and, subsequently, food intake, which has led to concerns about their impact on obesity. However, a new study suggests the opposite. It found no evidence that sugar replacements, whether artificial or natural sweeteners, increase hunger. In fact, the compounds were found to help reduce blood sugar levels, which means they actually reduce appetite, similar to how hormones react to sugary food.

These findings are especially important for people at risk of type 2 diabetes, who need a safer alternative to sugar without the risk of increased hunger or cravings.

“The use of sweeteners and sweetness enhancers has received a lot of negative attention, including high profile publications linking their consumption with impaired glycaemic response, toxicological damage to DNA and increased risk of heart attack and stroke. These reports contribute to the current befuddlement concerning the safety of sweeteners and sweetness enhancers among the general public and especially people at risk of metabolic diseases,” said lead author Graham Finlayson, who is a Professor of Psychobiology at the University of Leeds’ School of Psychology.

“Our study provides crucial evidence supporting the day-to-day use of sweeteners and sweetness enhancers for body weight and blood sugar control.” 

Zero-calorie sweet tooth

The study involved 53 overweight or obese adults. The researchers closely monitored how their bodies reacted to eating biscuits with sugar or two types of sweeteners: Stevia, a natural sugar substitute, or Neotame, an artificial sweetener. Unlike previous studies that focused on the effects of artificial sweeteners in beverages like Diet Coke, this research looked at solid food, assessed more than one sweetener, and included more male and female volunteers.

The participants underwent three two-week phases, during which they consumed biscuits filled with different sweeteners: sugar, the natural sweetener Stevia, or the artificial sweetener Neotame. There was a break of 14-21 days between each phase, and the first and last days were conducted in a lab setting.

Upon arriving at the lab after fasting overnight, researchers took blood samples from the participants to measure baseline glucose, insulin, and appetite-related hormone levels. Participants also provided ratings of their hunger and food preferences.

After eating the biscuits, participants reported on their feelings of fullness over several hours. The study also monitored changes in glucose and insulin levels, along with ghrelin (the hunger hormone), glucagon-like peptide 1, and pancreatic polypeptide levels —hormones that play roles in food intake and appetite.

The findings showed that neither type of sweetener affected appetite or hormonal responses when compared to sugar. However, insulin and blood sugar levels were notably lower two hours post-consumption, indicating a difference in how the body processes these sweeteners.

“The findings show that sweeteners are a helpful tool to reduce intake of added sugar without leading to a compensatory increase in appetite or energy intake, thereby supporting the usefulness of sweeteners for appetite, energy and weight management,” said co-author Professor Anne Raben, from the University of Copenhagen, Denmark. 

It’s still uncertain

In 2020, researchers at Boston Children’s Hospital studied what happens when soda drinkers switch to drinking water or artificially sweetened beverages. They monitored 203 adults who consumed at least one sugary beverage daily. After following the participants for a year, the researchers found no significant differences in weight gain between those who consumed artificially sweetened beverages and those who drank sugar soda. There were also no variations in metabolic health markers, including cholesterol and triglyceride levels.

“Simply restricting sugar from foods without substitution may negatively impact its taste or increase sweet cravings, resulting in difficulties sticking to a low-sugar diet. Replacing sugars with sweeteners and sweetness enhancers in food products is one of the most widely used dietary and food manufacturing strategies to reduce sugar intake and improve the nutritional profile of commercial foods and beverages,” said lead author Dr. Catherine Gibbons, Associate Professor at the University of Leeds.

Despite the results, artificial sweeteners are still causing disagreement. Despite many years of widespread use, it’s still not certain whether consuming them heavily for many years can have unintended negative health effects. One recent 2023 study, for example, connected aspartame to difficulties in learning and remembering.

“The short answer is that artificial sweeteners are probably better than sugar, but not by much,” Dr. Robert Lustig, an obesity expert and professor emeritus at the University of California, San Francisco, told the New York Times.

The results were published in The Lancet.