The study included 17 severely obese people who didn’t consume artificial sweeteners often and weren’t diagnosed with diabetes .

The artificial sweetener sucralose (Splenda®) is capable of changing the body’s insulin response, researchers at Washington University School of Medicine reported in the journal Diabetes Care.

First author M. Yanina Pepino, PhD, research assistant professor of medicine, said: “Our results indicate that this artificial sweetener is not inert – it does have an effect. And we need to do more studies to determine whether this observation means long-term use could be harmful.”

Study participants had an average body mass index (BMI) of around 42, which is 12 points above the threshold of obesity.

The volunteers were given either water or sucralose to drink before a glucose challenge test, which involved consuming a similar glucose dosage to the amount given as part of glucose-tolerance test.

The researchers wanted to determine whether insulin or blood sugar levels are affected by the combination of sucralose and glucose.

Pepino said that they particularly wanted to study obese people as “these sweeteners frequently are recommended to them as a way to make their diets healthier by limiting calorie intake.”

However, it should be noted that artificial sweeteners don’t necessarily help limit calorie intake. A previous study by scientists in the US suggested that consuming artificial sweeteners could make people put on weight because experiments on laboratory rats showed that those eating food sweetened with artificial sweeteners ate more calories than their counterparts whose food was sweetened with normal sugar.

The participants were each tested twice. They were first tested after drinkin water followed by glucose, and then after drinking sucralose followed by glucose.

Pepino commented:

“When study participants drank sucralose, their blood sugar peaked at a higher level than when they drank only water before consuming glucose. Insulin levels also rose about 20 percent higher. So the artificial sweetener was related to an enhanced blood insulin and glucose response.”

Pepino said that while the elevated insulin response suggests that a person is able to adjust insulin to spiking glucose levels, it could be detrimental because when people constantly secrete high levels of insulin it can lead to type 2 diabetes.