Researchers have found that a diet rich in vegetables, fruits, legumes, nuts, unrefined grains, olive oil and fish leads to longer telomeres, DNA sequences that act as protective caps for chromosome ends, in blood cells. Telomeres become shorter each time cell division occurs so their length is believed to be a measure of a cell's age.
Published in the journal The BMJ, the study involved data gleaned from the Nurses' Health Study, a prospective cohort study featuring 121,700 female registered nurses aged 30 to 55 years old across 11 U.S. states. The Nurses' Health Study began in 1976 but researchers for the current study only examined blood samples from 32,825 subjects given from 1989 to 1990. Alongside blood samples, the subjects' diets were also scored, with a higher score indicating closer adherence to a typical Mediterranean diet.
According to their results, women whose diets were scored higher had the tendency to have longer telomeres compared to those who scored lower. For each point that a diet scores higher, telomere length corresponded to around 1.5 years less of aging.
For instance, two subjects with a three-point difference in diet scores, on average, showed an aging difference of 4.5 years in their telomeres. This is similar to aging differences between smokers and non-smokers, active and less active individuals, and women with high and low phobic anxiety scores, which translate to 4.6 years, 4.4 years and 6 years, respectively.
"Our findings showed that healthy eating, overall, was associated with longer telomeres. However, the strongest association was observed among women who adhered to the Mediterranean diet," said Marta Crous-Bou, a postdoctoral fellow from the Channing Division of Network Medicine from the Brigham and Women's Hospital, an affiliate of the Harvard Medical School, and the study's lead author.
Researchers were not able to pinpoint which items in a Mediterranean diet was responsible for letting telomeres grow long, so further study will be needed, which will also address other limitations of the current study, like it didn't explore other influences the subjects' diets may have had and that many of the subjects were of European descent, meaning other telomere dynamics may have not been represented.
Nevertheless, the study affirms that the Mediterranean food represents the ideal diet, most especially when prevention of cardiovascular disease is a goal. Coupled with regular physical activity, eating a Mediterranean diet is key to health and longevity.
Aside from Crous-Bou, others who worked on the study include: Immaculata De Vivo (senior author); Frank B. Hu; Kathryn M. Rexrode; Qi Sun; Mengmeng Du; Bettina Julin; Jennifer Prescott; and Teresa T. Fung.
