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Results of large-scale epidemiologic studies have provided evidence for a significant association between sugar-sweetened beverages (SSBs) consumption and the risk of developing obesity-associated chronic diseases such as type 2 diabetes and cardiovascular disease. Indeed, recent studies from the Harvard Medical School have shown that people who consume one or two SSB per day have an increased risk of developing diabetes by more than 25%. On the other hand, smaller intervention studies have shown that consumption of SSBs not only caused weight gain, but also contributed to the storage of fat in the liver and in the abdomen, thereby contributing to cardiometabolic risk. However, whether the risk associated with SSB consumption is the result of years of exposure to unhealthy drinking habits or can be observed in a relatively short period of time is uncertain.

In a manuscript published in the latest issue of the American Journal of Clinical Nutrition, researchers from the University of California Davis present the results of a short-term exposure to SSBs on cardiovascular risk factors in apparently healthy adults between the age of 18 and 40 (http://ajcn.nutrition.org/content/early/2015/04/22/ajcn.114.100461.abstract). The authors performed a dose-response study on 85 men and women who consumed either 0%, 10%, 17,5% or 25% of their daily energy requirements from SSBs for two weeks. After the two-week period, only the participants in the 25% of daily calories from SSBs had increased their body weight (by less than one kilo). However, the authors reported a dose-response increase in blood lipid levels such as cholesterol and triglycerides. The most striking observation was the 35% increase in postprandial triglycerides (triglyceride levels measured after a meal) in the 25% of daily calories from SSBs. A dose-dependent increase in uric acid (a biomarker of fatty liver and cardiovascular risk) was also observed. The authors have performed a series of analyses, which showed that the increases in cardiovascular risk factors were independent of changes in body weight. However, changes in liver fat or abdominal fat were not measured. Additionally, although the consumption of SSB was closely monitored during the course of the study, the other nutrients consumed by the study participants was not, which precluded the authors to determine the precise amount of sugar that was consumed. However, the fact that study participants could eat whatever they wanted during the study probably resembles more to real life condition in opposition to a controlled feeding study. It is also important to point out that the amount of SSBs consumed in the four groups was not exaggerated and was (sadly) comparable to the consumption of SSB typically observed in Western societies.

The results of this study show unequivocally that even a short term exposure to SSBs significantly increases cholesterol levels and triglycerides, two powerful risk factors for heart disease. This study clearly supports the recommendation of the World Health Organization to reduce the consumption of added sugars to less than 10% of caloric intake and reinforces the notion that improving healthy drinking habits for instance by increasing water consumption is pivotal for the management of cardiovascular risk factors.