Opting for a diet version of your favourite soft drink may seem like the healthiest option, but new research suggests it could increase your risk of stroke, heart disease and even early death.
The large study, involving more than 80,000 women in the US, found that drinking two or more diet drinks a day – including fizzy drinks and fruit-based diet drinks – increased the risk of stroke by 23%.
Compared with women who consumed diet drinks less than once a week or not at all, women who consumed two or more artificially-sweetened drinks per day were also 29% more likely to develop heart disease and 16% more likely to die from any cause.
Further analysis showed that some groups of women were most at risk, with those drinking two or more diet drinks a day who were also obese having more than double the stroke risk than others. African-American women also had a higher risk of stroke.
The authors stressed that the study found a link but could not prove that diet drinks cause stroke and heart problems.
Dr Yasmin Mossavar-Rahmani, 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, 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.”
The research, published in the journal Stroke, included data from 81,714 post-menopausal women (who were aged 50 to 79 at the start of the study) and who were tracked for an average of 12 years. One serving of diet drink was regarded as 355ml.
Dr Mossavar-Rahmani said the study had not looked at individual artificial sweeteners, saying: “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.”
In response to the study, The International Sweeteners Association (ISA) said past reviews commissioned by the World Health Organisation found “no evidence that low calorie sweeteners could cause or increase the risk of cardiovascular disease″.
“It is important to highlight that, before being approved for use on the market, low calorie sweeteners are thoroughly tested and regulatory bodies around the world have consistently confirmed their safety and the lack of any negative health effect,” it said.