Many people try to cut back their sugar intake by replacing sugar with artificial sweeteners such as aspartame (NutraSweet®) and sucralose (Splenda®), sweet-flavored chemicals that do not introduce sugar into the blood stream (and thus, should not raise blood sugar levels). Doctors widely recommend these sweeteners as a way to help control calorie intake and reduce sugar intake. You may be surprised—and taken aback—to learn that sucralose actually raises blood sugar.

A recent study published in the journal Diabetes Care calls into question the use of sucralose as a sugar substitute in people concerned about blood sugar levels. In the study, 17 severely obese participants were given either water or sucralose to drink before consuming a glucose challenge test—about 75 grams of glucose—to mimic a sugar-containing meal. Blood sugar levels of those participants drinking sucralose rose higher than those drinking only water.

“Insulin levels also rose about 20 percent higher. So the artificial sweetener was related to an enhanced blood insulin and glucose response,” stated M. Yanina Pepino, PhD, lead researcher of the study. “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.”

She went on to explain that most studies on artificial sweeteners involved healthy, lean individuals, with the artificial sweetener given alone. But the reality is that many people consuming these sweeteners are not healthy, and they are eating the sweeteners along with others foods, often sugar-containing foods. “In obese people without diabetes, we have shown sucralose is more than just something sweet that you put into your mouth with no other consequences.”

More studies are needed to determine whether the blood sugar insulin effects contribute to long-term blood sugar control. Certainly this study is an eye-opener. I don’t recommend artificial sweeteners because they are man-made chemicals that we simply don’t know enough about. There are many natural sugar alternatives available. Choose lo han, stevia, erythritol, xylitol, or any of the natural options you prefer.