Soda and Cell Aging: Associations Between Sugar-Sweetened Beverage Consumption and Leukocyte Telomere Length in Healthy Adults From the National Health and Nutrition Examination Surveys

摘要

Objectives. We tested whether leukocyte telomere length maintenance, which underlies healthy cellular aging, provides a link between sugar-sweetened beverage (SSB) consumption and the risk of cardiometabolic disease. Methods. We examined cross-sectional associations between the consumption of SSBs, diet soda, and fruit juice and telomere length in a nationally representative sample of healthy adults. The study population included 5309 US adults, aged 20 to 65 years, with no history of diabetes or cardiovascular disease, from the 1999 to 2002 National Health and Nutrition Examination Surveys. Leukocyte telomere length was assayed from DNA specimens. Diet was assessed using 24-hour dietary recalls. Associations were examined using multivariate linear regression for the outcome of log-transformed telomere length. Results. After adjustment for sociodemographic and health-related characteristics, sugar-sweetened soda consumption was associated with shorter telomeres (b?=?–0.010; 95% confidence interval [CI]?=??0.020, ?0.001; P =?.04). Consumption of 100% fruit juice was marginally associated with longer telomeres (b?=?0.016; 95% CI?=??0.000, 0.033; P =?.05). No significant associations were observed between consumption of diet sodas or noncarbonated SSBs and telomere length. Conclusions. Regular consumption of sugar-sweetened sodas might influence metabolic disease development through accelerated cell aging. Sugar-sweetened beverages (SSBs), including soft drinks or sodas, fruit-flavored drinks, sports drinks, and energy drinks, are the largest source of added sugar in the US diet. 1,2 Between 1999 and 2008, it was estimated that adults aged 20 to 34 years consumed an average of 333 to 421 calories per day, and adults aged 35 years or older consumed an average of 236 to 260 calories per day from SSBs. 3 Because of these strikingly high levels of consumption, SSBs have emerged as an important target of public health efforts and policies. 4,5 In parallel to trends in SSB intake, the prevalences of obesity and type 2 diabetes have also increased in recent years. 6,7 Epidemiological studies have shown that regular consumption of SSBs is associated with increased risks of obesity, metabolic syndrome, type 2 diabetes, and cardiovascular disease. 8–11 However, the mechanisms for these associations are complex and not yet fully understood. There is evidence to suggest that excess calories (via lowered satiety) and high levels of insulin resistance, oxidative stress, and inflammation, may mediate these associations. 9 Because oxidative stress, inflammation, and insulin resistance are also associated with telomere shortening, impaired telomere length maintenance is a potential mechanism that may help to explain the association between SSB consumption and accelerated metabolic disease. 12–14 Telomeres are the DNA-protein caps at the end of chromosomes that promote chromosomal stability and protect the genomic DNA from damage. Telomere length naturally shortens with each cell cycle, and if it falls to a critical short length, the cell is no longer able to divide and often malfunctions. 15 In addition to biological age, telomere shortness has been linked to lifestyle behaviors and psychological stress. 16–22 In turn, shorter telomeres have been associated with increased risks of chronic diseases, including cardiovascular disease, diabetes, and some cancers. 17,23–27 In population studies, evidence exists for a causal role of impaired telomere maintenance in raising risks of pulmonary and cardiovascular disease. 28 To date, the associations between dietary intake and telomere length have been examined in only a few studies; results for most food groups and nutrients have been mixed. 13,29,30 Because of the known effects of SSBs on oxidative stress and insulin resistance, our objective in this study was to examine the associations between SSBs, diet soda, and 100% fruit juice consumption and telomere length in a large, nationally representative sample of healthy adults in the United States. We hypothesized that beverages with high sugar content would be the most detrimental to cellular aging, such that sugar-sweetened sodas and noncarbonated SSBs would show the strongest associations with telomere shortness.