Sugared soda consumption, cell ageing associated in new study

Sugar-sweetened soda consumption might promote disease independently from its role in obesity, according to University of California San Francisco (UCSF) researchers who found in a new study that drinking sugary drinks was associated with cell ageing.

The study revealed that telomeres – the protective units of DNA that cap the ends of chromosomes in cells – were shorter in the white blood cells of survey participants who reported drinking more soda. The findings have been reported online the American Journal of Public Health.

The length of telomeres within white blood cells – where it can most easily be measured – has previously been associated with human lifespan. Short telomeres also have been associated with the development of chronic diseases of ageing, including heart disease, diabetes and some types of cancer.

''Regular consumption of sugar-sweetened sodas might influence disease development, not only by straining the body's metabolic control of sugars, but also through accelerated cellular aging of tissues,'' said Elissa Epel, PhD, professor of psychiatry at UCSF and senior author of the study.

''This is the first demonstration that soda is associated with telomere shortness,'' Epel said. ''This finding held regardless of age, race, income and education level. Telomere shortening starts long before disease onset.  Further, although we only studied adults here, it is possible that soda consumption is associated with telomere shortening in children, as well.''

The authors cautioned that they only compared telomere length and sugar-sweetened soda consumption for each participant at a single time point, and that an association does not demonstrate causation. Epel is co-leading a new study in which participants will be tracked for weeks in real time to look for effects of sugar-sweetened soda consumption on aspects of cellular aging. Telomere shortening has previously been associated with oxidative damage to tissue, to inflammation, and to insulin resistance.

Based on the way telomere length shortens on average with chronological age, the UCSF researchers calculated that daily consumption of a 20-ounce soda was equivalent to an average of 4.6 years of telomere shortening. This effect on telomere length is comparable to the effect of smoking, or to the effect of regular exercise in the opposite, anti-aging direction, according to UCSF postdoctoral fellow Cindy Leung, ScD, from the UCSF Center for Health and Community and the lead author of the newly published study.