Among post-menopausal women, drinking multiple diet drinks
daily was associated with an increase in the risk of having a stroke
caused by a blocked artery, especially small arteries, according to research
published in Stroke, a journal of the American Heart Association.

This is one of the first studies to look at the association
between drinking artificially sweetened beverages and the risk of specific types
of stroke in a large, racially diverse group of post-menopausal women. While
this study identifies an association between diet drinks and stroke, it does
not prove cause and effect because it was an observational study based on
self-reported information about diet drink consumption.

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% more likely to have a stroke;
  • 31% more likely to have a clot-caused (ischaemic) stroke;
  • 29% more likely to develop heart disease (fatal or
    non-fatal heart attack); and
  • 16% more likely to die from any cause.

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

“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,” said Yasmin
Mossavar-Rahmani, PhD, lead author of the study and associate professor of
clinical epidemiology and population health at the Albert Einstein College of
Medicine in the Bronx, New York.

Researchers analyzed 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

“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.

The American Heart Association recently published a science
advisory that found there was inadequate scientific research to conclude
that low-calorie sweetened beverages do – or do not – alter risk factors for
heart disease and stroke in young children, teens or adults. The Association
recognises diet drinks may help replace high calorie, sugary beverages, but
recommends water (plain, carbonated and unsweetened flavored) as the best
choice for a no calorie drink.

“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, PhD, RD, 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. 

“The American Heart Association suggests water as the best
choice for a no-calorie beverage. However, for some adults, diet drinks with
low calorie sweeteners may be helpful as they transition to adopting water as
their primary drink. Since long-term clinical trial data are not available on
the effects of low-calorie sweetened drinks and cardiovascular health, given
their lack of nutritional value.


Reference: Mossavar-Rahmani
Y, et al.  Artificially Sweetened
Beverages and Stroke, Coronary Heart Disease, and All-Cause Mortality in the
Women’s Health Initiative. Stroke. Published 4 February 2019.