The study reported in the American Journal of Public Health reveals that the protective units of DNA that cap the ends of chromosomes in cells known also as telomeres were shorter in the white blood cells of survey participants who reported drinking more soda.
The authors only compared telomere length and sugar-sweetened soda consumption for each participant at a single time point and pointed out that an association does not demonstrate causation. Telomere shortening had previously been associated with oxidative damage to tissue, to inflammation and to insulin resistance.
This is the first demonstration that soda is associated with telomere shortness, said senior study author Elissa Epel, PhD., professor of psychiatry at UCSF. 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. Regular consumption of sugar-sweetened sodas might influence disease development not only by straining the bodys metabolic control of sugars, but also through accelerated cellular aging of tissues.
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 aging including diabetes, heart disease, and some types of cancer.
- The average sugar-sweetened soda consumption for all survey participants was 12 ounces.
- About 21 percent reported drinking at least 20 ounces of sugar-sweetened soda a day.
Based on the way telomere length shortens on average with chronological age, the researchers also calculated that consumption of a 20-ounce soda was associated with four to six years of additional biological aging. This effect of telomere length is comparable to the effect of smoking or to the effect of regular exercise in the opposite, anti-aging direction. The finding adds a new consideration to the list of links that has tied sugary beverages to obesity, metabolic syndrome, type 2 diabetes and cardiovascular disease.
It is critical to understand both dietary factors that may shorten telomeres, as well as dietary factors that may lengthen telomeres, added study lead author Cindy Leung, ScD from the UCSF Center for Health and Community. Here it appeared that the only beverage consumption that had a measurable negative association with telomere length was consumption of sugared soda.