What the studies really say….
Headlines recently suggest that diet drinks may increase your risk of becoming overweight, developing diabetes and a host of other cardiometabolic issues but what is this based on? The "Dietary patterns matter: diet beverages and cardiometabolic risks in the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) Study" published in the American Journal of Clinical Nutrition in 2012 sparked a lot of this talk. However, the study was based on a one month recollection of self-reported diet patterns. Dr. Mark Pereira from the School of Public Health at the University of Minnesota, Minneapolis recently spoke at Obesity Week and reports that he believes diet drinks are not the culprit in developing cardiometabolic disorders. In fact, he said that there is not sufficient research or evidence to base this claim on. However, he does acknowledge that there is a clear link between sugar-sweetened drinks and cardiometabolic disorders.
Another study published in the American Journal of Clinical Nutrition in 2012, "Sucrose-sweetened beverages increase fat storage in the liver, muscle, and visceral fat depot: a 6-mo randomized intervention study," demonstrates that sugar-sweetened beverage intake for 6 months is associated with an increase ectopic fat accumulation and lipids as compared to milk, diet cola, and water. The results of this study also suggest ingestion of diet cola reduced systolic blood pressure by 10-15% when compared with regular cola and that otherwise, diet cola had effects similar to water.
Dr. Pereira does acknowledge that studies have shown links between diet drink intake (and sugar sweetened beverages) with incident diabetes and other metabolic disturbances but he suggests that this may be a "reverse causality." This means that people who are already overweight or obese may believe that choosing a diet drink is a healthier alternative but the link to the cardiometabolic disorder is most likely related to being overweight/obese, not the consumption of diet drinks.
Further studies assessing diet drinks need to be completed to determine if diet drinks truly do have an association with the development of cardiometabolic disorders or if confounding factors such as obesity/being overweight (and a more detailed history of diet) is the main driving factor.
- There is not enough thorough current evidence to support diet drinks causing cardiometabolic disorders.
- Sugar sweetened beverages however have been strongly associated with increased central and visceral adipose development which can lead to cardiometabolic disorders.
- The study which has shown a potential link between diet drinks and cardiometabolic disorders relied on self-reported dietary habits and many of the participants were overweight/obese which could have been a confounding factor.
Duffey, K. Dietary patterns matter: diet beverages and cardiometabolic risks in the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) Study. Am J Clin Nutr. 2012 Apr;95(4):909-15
Maersk, M. Sucrose-sweetened beverages increase fat storage in the liver, muscle, and visceral fat depot: a 6-mo randomized intervention study. Am J Clin Nutr. 2012 Feb;95(2):283-9.