MedWire News: People who consume diet soft drinks on a daily basis have an increased risk for cardiovascular events such as stroke and myocardial infarction compared with nonconsumers, say US researchers.
"Artificially sweetened 'diet' soft drinks have been marketed as healthier alternatives due to their lack of calories," explain Hannah Gardener (University of Miami Miller School of Medicine, Florida) and colleagues.
"However, recent studies suggested that diet soft drink consumption may also be associated with health consequences, particularly Type 2 diabetes and the metabolic syndrome, risk factors for cardiovascular disease (CVD), ischemic stroke, and all-cause mortality," they add.
To assess the effects of soft drink consumption on combined cardiovascular events (stroke, myocardial infarction, vascular death), the researchers recruited 2564 men and women (36% men) from the Northern Manhattan Study. They were aged 69 years on average and were 20% White, 23% Black, and 53% Hispanic.
The study participants filled out a food frequency questionnaire at baseline to evaluate both normal and diet soft drink consumption. Consumption of either type of drink was classified as none (less than 1 drink/month), light (1 drink/month to 6 drinks/week), and daily (1 drink/day). The cohort was then followed-up for incident cardiovascular events.
Over 10 years of follow-up, 591 combined cardiovascular events occurred in the cohort. Gardener and team found that after controlling for a variety of factors including age, gender, ethnicity, education, body mass index, smoking, and physical activity, as well as dietary factors such as fat and protein intake, people who consumed diet soft drinks on a daily basis were significantly more likely to experience cardiovascular events over the follow-up period than nonconsumers (hazard ratio [HR]=1.46).
Further adjustment for comorbidities such as presence of the metabolic syndrome, peripheral vascular disease, hypertension, and hypercholesterolemia, did not invalidate the association (HR=1.43).
Of note, the team found no association between consumption of normal soft drinks and cardiovascular events after adjusting for the same risk factors.
"Our results suggest a potential association between daily diet soft drink consumption and vascular outcomes. However, the mechanisms by which soft drinks may affect vascular events are unclear," said Gardener in a press statement.
"There is a need for further research before any conclusions can be drawn regarding the potential health consequences of diet soft drink consumption," she added.
The results of this study are published in the Journal of General Internal Medicine.
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