Neva Cochran, MS, RDN, LD
Aspartame has been approved for use as a sweetener in foods and beverages in the U.S. for over three decades. A primary reason for use of low calorie sweeteners (LCS) like aspartame is to reduce calorie intake from sugar to promote weight loss and help manage blood glucose levels in individuals with diabetes. Recent reports estimate that 25% of children and 41% of adults consume products with LCS.
In a new study published in the April 2018 Journal of Nutrition (1) researchers at Purdue University and Indiana University School of Medicine evaluated the effect of daily aspartame consumption by healthy adults on glycemic responses, appetite, body weight and body composition. The study was prompted by the continuing controversy related to aspartame use among some individuals and groups even though the U.S Food and Drug Administration (FDA) and numerous international organizations have long recognized it as safe for human consumption. Research has also documented its effectiveness in lowering calorie intake to aid in weight loss.
The authors note that recent large meta-analyses demonstrated that LCS use is associated with lower body mass index (BMI). Individuals in the National Weight Control Registry who have maintained a significant weight loss for several years commonly use LCS as well. In addition, the American Heart Association, the Academy of Nutrition and Dietetics and the Canadian Diabetes Association have stated that LCS either moderate or have no effect on postprandial glycemia. Their use has also been associated with a higher Healthy Eating Index.
While claims have been made to the contrary, aspartame and other LCS do not stimulate greater perceived sweetness than sucrose according to prior studies. Nor has research shown that aspartame stimulates insulin release or that consuming LCS increases blood glucose afterward. In fact, it has actually been shown to lower blood glucose.
About the Study
One hundred subjects were randomly assigned to one of three groups: no aspartame, 350 mg aspartame/day (equivalent to one diet soda/day or the mean intake for aspartame consumers) or 1050 mg aspartame/day (equivalent to three diet sodas/day or amount approximating the 95th percentile for aspartame consumers). Participants were 18–60 years old, with normal BMI, not taking medications that affect metabolism or appetite, normal fasting serum glucose levels, no aspartame sensitivity and no or low use of LCS, including aspartame. Participants consumed the aspartame through fruit-flavored beverages and capsules containing the sweetener.
The glycemic response to each treatment was measured at the beginning of the study and after 12 weeks of daily beverage and capsule intake. Blood glucose levels were not significantly higher in the 350- or 1050-mg/day aspartame consumption groups compared to the no-aspartame group, either at the onset or after 12 weeks. In addition, there were no significant differences in hunger, desire to eat, fullness or thirst. And there was no effect of the treatments on body weight, percent body fat or percent fat-free mass.
This study confirms and strengthens the current understanding of the effects of aspartame on glycemia: that daily ingestion of aspartame for 12 weeks, in amounts equivalent to one or three cans of diet soda/day, did not produce any changes in glycemia, insulin release, appetite, body weight or body composition in healthy, lean adults. While the study was not intended to evaluate aspartame’s usefulness for weight loss, it did not indicate that its use as a replacement for caloric sweeteners would be counterproductive.
Applications for Practice
These results can assure registered dietitians and other health professionals that patients and clients can consume aspartame in concentrations realistic for healthy free-living adults without adverse effects on blood sugar. Although the data from this study cannot be used to draw comparisons for those with diabetes, previous studies have shown benefits of LCS in diabetes management.
Study researcher, Richard Mattes, PhD, RD, emphasizes these key points:
- Work around the world continues to confirm the safety of aspartame and LCS.
- The preponderance of evidence indicates that there are no negative impacts with amounts commonly consumed.
- Studies with the strongest scientific designs indicate the use of LCS is associated with lower body weight.
- There are few tools available for individuals to moderate energy intake. For some individuals, certain sweeteners, including LCS, may be useful, for others they may not be.
(1) “Aspartame Consumption for 12 Weeks Does Not Affect Glycemia, Appetite, or Body Weight of Healthy, Lean Adults in a Randomized Controlled Trial” J Nutr 2018; 148:650–657
Neva Cochran, MS, RDN, LD is a registered dietitian nutritionist based in Dallas. She serves as a nutrition communications consultant to a variety of food and nutrition organizations, including the Calorie Control Council. She is passionate about promoting fact-based food and nutrition information to help people enjoy nutritious eating. Follow her on Twitter @NevaRDLD and check out her blog at www.NevaCochranRD.com.