Chalk up two more losses for artificial sweeteners in the realms of obesity and diabetes research.
Now, the results of a population study and a mouse trial further undermine the presumed but unproven weight-control and diabetes-deterrence value of diet drinks and a common non-caloric sweetener.
In the constant battle of the bulge, many reach for artificially sweetened diet sodas as substitutes for sugary beverages, which contribute a whopping 20 percent of the calories in the average American's diet (see “The Calories We Quaff”).
But two studies presented last month at the American Diabetes Association's Scientific Sessions in San Diego suggest this might be a self-defeating strategy.
Scientists from The University of Texas Health Science Center San Antonio linked diet soft drinks to bigger waistlines in people … and a second study found that aspartame raised fasting glucose (blood sugar) levels in diabetes-prone mice.
According to co-author Helen P. Hazuda, Ph.D., “Data from this and other prospective studies suggest that the promotion of diet sodas and artificial sweeteners as healthy alternatives may be ill-advised. They may be free of calories but not of consequences.” (UT 2011)
Human study disses diet sodas
The Health Science Center team analyzed data from 474 participants in the San Antonio Longitudinal Study of Aging, or SALSA … a large, 20-year-long study among elderly Mexican Americans and European Americans (Fowler SP, Williams K, Hazuda HP 2011).
Measures of height, weight, waist circumference, and diet soda intake were recorded when people enrolled in the SALSA study, and at three follow-up exams that took place over the next decade.
The researchers compared long-term changes in waist circumference for diet soda users versus non-users, and adjusted the results for diet and lifestyle factors affecting weight gain or loss.
Overall, the diet soft drink users experienced 70 percent greater increases in waist circumference compared with non-users.
Frequent users, who said they consumed two or more diet sodas a day, experienced waist circumference increases that were 500 percent greater than those of non-users.
Abdominal fat is a major risk factor for diabetes, cardiovascular disease, cancer, and other chronic conditions.
As the authors wrote, “These results suggest that, amidst the national drive to reduce consumption of sugar-sweetened drinks, policies that would promote the consumption of diet soft drinks may have unintended deleterious effects.” (UT 2011)
Aspartame consumption raises blood sugar in diabetes-prone mice
In a related study, University of Texas researchers studied the relationship between aspartame intake and blood levels of fasting glucose and insulin in 40 diabetes-prone mice (Fowler SP, Halada GV, Fernandes G. 2011).
Aspartame is the common artificial sweetener widely used in diet sodas and other products.
One group of the mice ate chow to which both aspartame and corn oil were added; the other group ate chow with the corn oil added but not the aspartame.
After three months on this high-fat diet, the mice in the aspartame group showed elevated fasting glucose levels but equal or diminished insulin levels.
These twin changes are associated with early declines in the functioning of pancreatic beta cells, which produce insulin to get blood sugar into cells, which also lowers blood sugar levels after a meal.
Senior author Gabriel Fernandes, Ph.D., made a key point:
“These results suggest that heavy aspartame exposure might potentially directly contribute to increased blood glucose levels, and thus contribute to the associations observed between diet soda consumption and the risk of diabetes in humans.” (UT 2011)
Both studies were funded by the Institute for the Integration of Medicine and Science (IIMS), which oversees the university's Clinical and Translational Science Award (CTSA).
This National Institutes of Health-funded program encourages the rapid translation of scientific discoveries from the laboratory to policies and practical applications for public health.
- University of Texas Health Science Center at San Antonio (UT). Related studies point to the illusion of the artificial. June 27, 2011. Accessed at http://www.eurekalert.org/pub_releases/2011-06/uoth-rsp062711.php
- Fowler SP, Williams K, Hazuda HP. Diet Soft Drink Consumption Is Associated with Increased Waist Circumference in the San Antonio Longitudinal Study of Aging. Abstract No. 0062-OR. Accessed at http://ww2.aievolution.com/ada1101/index.cfm?do=abs.viewAbs&abs=10061. American Diabetes Association 71st Scientific Sessions, June 24 - 28, 2011, San Diego Convention Center - San Diego, California
- Fowler SP, Halada GV, Fernandes G. Aspartame Consumption Is Associated with Elevated Fasting Glucose in Diabetes-Prone Mice. Abstract No. 0788-P. Accessed at http://ww2.aievolution.com/ada1101/index.cfm?do=abs.viewAbs&abs=10845. American Diabetes Association 71st Scientific Sessions, June 24 - 28, 2011, San Diego Convention Center - San Diego, California