SAN FRANCISCO—Heavy consumption of artificially sweetened beverages was associated with almost twice the risk of diabetes in a long-term, community-based prospective study, researchers reported here at the American Diabetes Association annual meeting.
“Our finding of increased incidence of metabolic syndrome among daily diet soda users is consistent with earlier reports from the Framingham Heart Study and the Atherosclerosis Risk in Communities Study,” said Sharon P. Fowler, MPH, faculty associate in clinical epidemiology at the University of Texas Health Science Center at San Antonio and coordinator of the current investigation.
“The results are also consistent with our own earlier report of increased weight gain and obesity incidence among frequent users of artificially sweetened beverages. Taken together, the data raise the question of whether doctors counseling their patients about diet should in fact be recommending liberal use of artificial sweeteners.”
She added that “nephrologists have a unique opportunity to work with their patients to try to forestall and/or minimize the relentless cascade of complications which too often result from diabetes.”
Fowler and colleagues examined the association between artificial sweetener use and diabetes in 3,682 Mexican Americans and non-Hispanic whites enrolled in the ongoing San Antonio Heart Study. Although widely recommended as a healthy alternative to sugar to curb increasing obesity levels, the push for artificial sweeteners is increasingly being challenged, she pointed out.
Recent studies have raised the question of whether artificially sweetened beverages, including diet sodas, may in fact have contributed to the significantly increased rate of long-term weight gain, overweight, obesity, and metabolic syndrome observed in recent years.
Seven- to eight-year follow-up data revealed a dose-response relationship between the consumption of artificially sweetened beverages at baseline and the incidence of type 2 diabetes. Heavy consumption of artificially sweetened beverages—defined as 22 or more per week—was associated with a 91% increase in diabetes incidence. The increase was even larger (125%) in individuals with a family history of diabetes. Beverages included artificially sweetened coffee, tea, and soft drinks.
The association persisted even after controlling for such potentially confounding variables as baseline BMI, change in BMI, family history of diabetes, fasting glucose and lipid values, baseline two-hour glucose values, systolic BP, and change in physical activity levels.
“If the relationship between heavy artificial sweetener consumption and diabetes is indeed a causal one,” Fowler told Renal & Urology News, “it may be that diet soda use is a marker for prior use of sugar-sweetened sodas, which set individuals on a trajectory toward obesity, metabolic syndrome, and diabetes that continued even though they switched to diet sodas. So individuals may have been on the path to diabetes before their switch to artificial sweeteners—a path that continued despite their switch.”
It is also possible, however, that individuals who use artificial sweeteners may increase their calorie intake from other sources and, in some cases, even inadvertently increase their overall calorie intake. Additionally, in the San Antonio study, consumers of artificially sweetened beverages tended to have lower exercise levels compared with non-users.
While the finding does not prove that heavy consumption of artificially sweetened beverages increases diabetes risk, it does call into question the notion that artificial sweeteners are innocuous “risk-lowering dietary components,” Fowler commented.
She added: “I hope very much that nephrologists will consider very carefully the question of whether these chemicals actually promote the health and survival of their patients, or whether these substances might actually be accelerating the severity of diabetes-related complications, and thus erode quality of life for their patients. I would challenge any doctor to look at a label on a can of diet soda and find anything good for the body [or nutritious].”