28 June 2011
Artificial sweeteners contributing directly to diabetes risk
by Kate Melville
The findings from two new studies have prompted US health scientists to state that the promotion of diet sodas and aspartame sweeteners as healthy alternatives may be "ill-advised." Their findings were presented last weekend at the American Diabetes Association's Scientific Sessions.
Both studies were conducted by researchers from The University of Texas Health Science Center San Antonio. In the first, participants had their height, weight, waist circumference and diet soda intake recorded over a 10-year period. The results were adjusted for waist circumference, diabetes status, leisure-time physical activity level, neighborhood of residence, age and smoking status at the beginning of each interval, as well as sex, ethnicity and years of education.
The findings showed that diet soft drink users, as a group, 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.
"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," the researchers noted.
In the second study, the research group examined the relationship between oral exposure to aspartame (an artificial sweetener widely used in diet sodas) and fasting glucose and insulin levels in mice.
One group of the mice ate food to which both aspartame and corn oil were added; the other group ate food 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, consistent with early declines in pancreatic function. "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," commented study author Dr. Gabriel Fernandes.
Summarizing the findings from the two studies, Helen P. Hazuda, chief of the institute's Division of Clinical Epidemiology, said; "[the data] 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."