Newest Study Confirms a Soda a Day Ups Diabetes Risk by 20%

Megan Brooks

April 25, 2013

April 25, 2013 — Drinking one 12-ounce sugar-sweetened soft drink a day can increase the risk of type 2 diabetes by 22%, a new study from Europe suggests.

The results corroborate research conducted in North American populations.

Collectively, the findings suggest that "clear" population-based messages on the deleterious effect of these beverages on health "should be given," the study team says.

Mounting Evidence That 1 Can a Day Ups Diabetes Risk by a Fifth

The findings, from a study by Dora Romaguera, PhD, from the School of Public Health, Imperial College London, United Kingdom, and colleagues, are published online in Diabetologia April 24.

They used the longitudinal European Prospective Investigation into Cancer and Nutrition (EPIC) study to evaluate ties between intake of sweet beverages (juices and nectars, sugar-sweetened soft drinks, and artificially sweetened soft drinks) and type 2 diabetes. They established a case-cohort design comprising 12,403 incident type 2 diabetes cases and a random subcohort of 16,154 individuals.

One 12-oz daily increment in sugar-sweetened or artificially sweetened soft-drink consumption was associated with the development of type 2 diabetes (hazard ratios [HRs]), 1.22 and 1.52, respectively).

After adjustment for energy intake and body mass index (BMI), which are thought to mediate the association between sugar-sweetened soft-drink consumption and diabetes, the association of sugar-sweetened soft drinks with type 2 diabetes was attenuated somewhat but persisted nonetheless (HR, 1.18, 95% CI 1.06 — 1.32).

However, the association of artificially sweetened soft drinks became statistically nonsignificant (HR, 1.11) following similar adjustment. Juice and nectar consumption was not associated with type 2 diabetes incidence.

As reported by Medscape Medical News, a recent study from France found a link between drinking diet soda (and regular soda) and increased risk for type 2 diabetes in women.

The researchers say the increased risk of diabetes among sugar-sweetened soft-drink consumers in Europe mirrors that seen in a meta-analysis conducted in North America, which found a 25% increased risk of type 2 diabetes associated with a 12-oz daily increment of sugar-sweetened beverage consumption.

Dr. Romaguera and colleagues say the strengths of their analysis include its "power, the prospective design, and the European population drawn from different centers." But the fact that dietary exposures and anthropometry were assessed only once at baseline, without their taking into account possible modifications of diet and weight change during follow-up, is 1 possible limitation, they note.

Another Nail in the Coffin for Sodas

Asked for comment, Rachel K. Johnson, PhD, professor of nutrition at the University of Vermont, Burlington, said the findings of this paper are "important because they come from a well-designed, prospective research trial conducted in a large sample of Europeans who were healthy at the beginning of the study. [This] enabled the researchers to determine the association between…different types of sweet beverages and the incidence of diabetes in a European population with a wide range of consumption.

"This study is yet another nail in the coffin for sugar-sweetened beverages. The American Heart Association recommends that you consume no more than 450 calories (36 ounces) of sugar-sweetened beverages a week," Dr. Johnson noted.

What the EPIC study shows is "absolutely consistent with what we have seen in studies in the US," Robert Ratner, MD, chief scientific and medical officer for the American Diabetes Association, told Medscape Medical News.

He said studies to date "give us a public-health message that we really need to listen to. In our minds, the data are overwhelming and convincing. We believe that reducing the consumption of sugar-sweetened beverages through public information, education, and public-health policy is a critical piece to reducing the development of diabetes."

In the United States, the watchdog group Centers for Science in the Public Interest (CSPI) has petitioned authorities to regulate sugar-sweetened beverages, saying they are hazardous to human health and need to be regulated.

However, in New York City, Mayor Michael Bloomberg's proposal to ban supersized sugary drinks from restaurants, movie theaters, and other establishments was invalidated by a judge in March before it took effect.

Funding for the study by Dr. Romaguera and colleagues was provided by the European Commission Sixth Framework Programme. The authors and Dr. Johnson have reported no relevant financial relationships.

Diabetologia. Published online April 24, 2013. Article (zip file)