High-intensity sweeteners often are recommended by health and nutrition experts, not just for calorie reduction, but to control blood sugar. However a recent study (“Sucralose affects glycemic and hormonal response to an oral glucose load," Diabetes Care, doi: 10.2337/dc12-2221) questions whether this is actually helpful when the sweetener is sucralose.
Researchers at Washington University School of Medicine, St. Louis found that sucralose, a sweetene sold under the brand name Splenda®, might modify how the human body deals with sugar. The small study used 17 severely obese people (an average body mass index of just over 42). Subjects did not have diabetes nor regularly used artificial sweeteners. “We wanted to study this population because these sweeteners frequently are recommended to them as a way to make their diets healthier by limiting calorie intake," says one of the study’s author M. Yanina Pepino, PhD, research assistant professor of medicine .
The test subjects drank either plain water or sucralose before they took a glucose challenge test. “When study participants drank sucralose, their blood sugar peaked at a higher level than when they drank only water before consuming glucose," Pepino explained. “Insulin levels also rose about 20% higher. So the artificial sweetener was related to an enhanced blood insulin and glucose response."
The researchers don’t actually know if this is harmful. The elevated insulin response from sucralose means the person makes sufficient insulin to deal with spiking glucose levels, which is good. But excess insulin secretion can promote insulin resistance, which can lead to type 2 diabetes.
Researchers theorize that this effect may occur because studies found the gastrointestinal tract and pancreas can detect sweet foods and drinks, including those with artificial sweeteners like sucralose, with receptors similar to those in the mouth. This causes an increased insulin release and also can increase glucose absorption.
Pepino said further studies are needed to examine the potential mechanism that would cause sucralose to influence glucose and insulin levels, as well as if those changes are harmful. She noted that a 20% increase in insulin may or may not be clinically significant.
