Diet drinks may be linked with strokes among post-menopausal women

It turns out that drinking multiple diet drinks daily may not be a very good idea for post menopausal women. A new study finds that it is associated with an increased risk of having a stroke caused by a blocked artery.

The study was published in Stroke, a journal of the American Heart Association.

The study is one of the first to look at the association between drinking artificially sweetened beverage and the risk of specific types of stroke in a large, racially diverse group of post-menopausal women.

Compared with women who consumed diet drinks less than once a week or not at all, women who consumed two or more artificially sweetened beverages per day were:

23 per cent more likely to have a stroke;

31 per cent more likely to have a clot-caused (ischemic) stroke;

29 er cent more likely to develop heart disease (fatal or non-fatal heart attack); and

16 per cent more likely to die from any cause.

Furthermore, researchers found risks were higher for certain women. Heavy intake of diet drinks, defined as two or more times daily, more than doubled stroke risk in:

-women without previous heart disease or diabetes, who were 2.44 times as likely to have a common type of stroke caused by blockage of one of the very small arteries within the brain;

-obese women without previous heart disease or diabetes, who were 2.03 times as likely to have a clot-caused stroke; and

-African-American women without previous heart disease or diabetes, who were 3.93 times as likely to have a clot-caused stroke.

Speaking about the study, lead author of the study Yasmin Mossavar-Rahmani said, "Many well-meaning people, especially those who are overweight or obese, drink low-calorie sweetened drinks to cut calories in their diet. Our research and other observational studies have shown that artificially sweetened beverages may not be harmless and high consumption is associated with a higher risk of stroke and heart disease."

Researchers analysed data on 81,714 postmenopausal women (age 50-79 years at the start) participating in the Women's Health Initiative study that tracked health outcomes for an average of 11.9 years after they enrolled between 1993 and 1998.

At their three-year evaluation, the women reported how often in the previous three months they had consumed diet drinks such as low calorie, artificially sweetened colas, sodas and fruit drinks. The data collected did not include information about the specific artificial sweetener the drinks contained.

The results were obtained after adjusting for various stroke risk factors such as age, high blood pressure, and smoking. These results in postmenopausal women may not be generalisable to men or younger women. The study is also limited by having only the women's self-report of diet drink intake.

"We don't know specifically what types of artificially sweetened beverages they were consuming, so we don't know which artificial sweeteners may be harmful and which may be harmless," Mossavar-Rahmani said.

"Unfortunately, current research simply does not provide enough evidence to distinguish between the effects of different low-calorie sweeteners on heart and brain health. This study adds to the evidence that limiting use of diet beverages is the most prudent thing to do for your health," said Rachel K. Johnson, Ph.D., R.D., professor of nutrition emeritus, University of Vermont and the chair of the writing group for the American Heart Association's science advisory, Low-Calorie Sweetened Beverages and Cardiometabolic Health.