Foods with a high glycemic index, such as sugar-sweetened soft drinks, desserts, and white bread products, contain sugars that are rapidly absorbed into the bloodstream, causing hyperglycemia (high blood glucose). Regular consumption of high glycemic foods may lead to insulin resistance, type 2 diabetes, and obesity. Low-calorie sweeteners (i.e., artificial sweeteners) such as allulose have a low glycemic index and can be used in place of sugar to reduce the intake of calories and high-glycemic carbohydrates; however, the effects of allulose in addition to sugar require further investigation. Findings published in a new report show that allulose significantly reduces glucose and insulin levels following sugar consumption.
Allulose is a rare sugar that can be found in small amounts in some fruits and grains and is sold as a low-calorie sweetener. Allulose is an epimer of fructose, meaning its chemical structure is very similar to fructose, giving it a nearly identical taste and texture; however, allulose provides only 0.4 calories per gram, compared to 4 calories per gram of fructose. A meta-analysis of previous research found that small doses of allulose improved glucose and insulin regulation; however, additional randomized controlled trials are needed, especially in Western populations and in people without type 2 diabetes.
The researchers recruited 30 participants (average age, 33 years) without type 2 diabetes and asked them to follow an individualized diet plan that provided 50 to 65 percent of calories from carbohydrates for up to eight weeks. Participants completed five study visits with one to two weeks between visits. At each visit, the researchers gave participants a beverage containing 50 grams of fructose (the amount in about 16 ounces of sugar-sweetened soda) with escalating doses of allulose (0, 2.5, 5, 7.5, or 10 grams). They measured glucose and insulin levels in the blood 0, 30, 60, 90, and 120 minutes after beverage consumption.
Allulose consumption reduced plasma glucose levels among participants in a dose-dependent manner, meaning as the dose of allulose increased from 0 to 10 grams, glucose levels at each time point decreased. The relationship between allulose and lower glucose levels was statistically significant at the 30-minute time point when either 7.5 or 10 grams of allulose was added to the fructose beverage. Compared to consuming a fructose beverage with no added allulose, the 10-gram dose of allulose also significantly decreased insulin levels 30 minutes after beverage consumption.
These findings demonstrate that allulose decreased glucose and insulin levels when added to a high-sugar beverage in healthy young people without diabetes. The authors suggested that future studies explore more of the mechanisms underlying these results.