Recent studies have indicated that adults and teenagers who regularly drink diet beverages tend to be overweight and at increased risk for metabolic syndrome, a forerunner for heart disease and diabetes. At a March 2014 meeting of the nation's cardiologists, a presentation was made that strengthens the link between consumption of diet soft drinks and increased risk for heart attack, stroke, and other cardiovascular complications in older women. Although the study did not address when the study participants started drinking diet drinks, the increased risk for cardiovascular distress likely begins earlier and builds with increased consumption.

Soda canDr. Ankur Vyas, a cardiovascular diseases fellow at the University of Iowa Hospitals and Clinics, presented the findings of his team's research on March 30 at the 63rd Annual Scientific Session of the American College of Cardiology. Vyas says interest in the topic of study was chosen because "there was a relative lack of data about diet drinks and cardiovascular outcomes and mortality."

The Vyas study was based on a questionnaire survey completed by 59,614 women already enrolled in the Women's Health Initiative Observational Study. The participants were all healthy postmenopausal women with an average age of 62.8. None had previous diagnosis of cardiovascular disease and all were still living 60 days after completion of the survey.

The survey asked women to report how many diet drinks (12-ounce diet sodas and diet fruit drinks) they consumed during a three-month period. The study followed each woman an average of 8.7 years for cardiovascular conditions that included cardiovascular death, congestive heart failure, coronary heart disease, coronary revascularization procedure, heart attack, ischemic stroke, and peripheral arterial disease.

The study data was adjusted to account for demographic and cardiovascular risk factors that included body mass index, diabetes, energy intake (calories), high cholesterol levels, hormone therapy, hypertension, physical activity, salt intake, smoking, and sugar-sweetened beverage consumption.

The women were divided into four groups based on level of consumption:

  • 2+ drinks a day
  • 5 to 7 per week
  • 1 to 4 per week
  • Zero to 3 per month

Some findings of the Vyas study include:

  • Women who drank two or more diet beverages a day tended to be younger, were more likely to be smokers, had a higher body mass index, and were more likely to be diabetic or have high blood pressure.
  • 8.5% of the women drinking 2+ diet beverages a day suffered cardiovascular events, including diagnosis, during the follow-up period.
  •  6.9% of the women in the 5-to-7-per-week group experienced cardiovascular events.
  • 6.8% did so in the 1-to-4-per-week group.
  • 7.2% in the zero-to-3-per-month group.

Vyas says, "We only found an association so we can't say that diet drinks cause these problems" but the growing body of evidence indicating health risks associated with diet drinks "could have major public health implications."

Source: "Too many diet drinks may spell heart trouble for older women (press release)." EurekAlert! EurekaAlert / American College of Cardiology. 29 Mar, 2014. Web. Apr 6, 2014.