San Francisco study associates sugar-sweetened soda with cell aging

The scientists led by senior author Elissa Epel, professor of psychiatry at University of California San Francisco, found shorter telomeres – protective DNA units that cap the ends of chromosomes in cells – in the immune cells of soda drinkers.

The team claims it study breaks new ground by showing this association, with short telomeres in white blood cells – where they are most easily measured – previously associated with the development of chronic aging diseases including heart disease, diabetes and some cancers.

Findings held regardless of age, race, income and education​

"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,"​ 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,”​ she added.

The UCSF researchers measured telomeres using stored DNA from 5,309 subjects aged 20-65, with no history of diabetes of cardiovascular disease, who took part in the US National Health and Nutrition Examination Survey from 1999-2002.

Explaining that telomere length tends to shorten as people age, the UCSF researchers calculated that drinking 20oz of soda per day was associated with 4.6 years of additional biological aging.

(Average sugar-sweetened soda consumption for all participants was 12oz; around 21% of this nationally representative sample reported drinking at least 20oz per day.)

‘Critical’ to understand dietary influence on telomere length​

Cindy Leung, a UCSF postdoctoral fellow and lead study author, said this effect on telomere length was comparable to that associated with smoking, while exercise is believed to lengthen telomeres.

"It is critical to understand both dietary factors that may shorten telomeres, as well as dietary factors that may lengthen telomeres,"​ Leung said.

"Here it appeared that the only beverage consumption that had a measurable negative association with telomere length was consumption of sugared soda,”​ she added.

But the authors admit the association does not demonstrate causation, while they only compared telomere length and sugar-sweetened soda consumption for each person at a single​ time point.

Professor 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.