Telomeres – the protective DNA caps on every chromosome which shorten over time as a cell ages – have been correlated with chronic diseases in hundreds of studies. A shorter telomere equates to an aging cell, and the cumulative effect of this may manifest as the degenerative diseases commonly associated with aging, including heart disease, cancer and dementia. Low vitamin D has also been linked to several chronic diseases. In this study, researchers sought to link the two – low vitamin D and shorter telomeres. Telomere length was measured via PCR (polymerase chain reaction) on 4260 American adults ranging in age from 20 years old to over 60. In the age group of 40-59 years, blood levels of vitamin D were correlated to telomere length. In other words, higher vitamin D = longer telomeres.
In a different study on participants from the same government-sponsored survey (NHANES, National Health and Nutrition Examination Survey), 4347 American adults were evaluated for vitamin D levels and telomere length. After adjusting for common demographic factors (age, race, education), higher vitamin D was linked to longer telomeres. However, after adjusting for common physical factors (smoking, BMI, activity levels), no correlation was seen. This suggests that vitamin D may very well be correlated with telomere length, but other factors play such a big role in healthy aging (such as not smoking or getting regular exercise) that these factors make the vitamin D-telomere connection less clear.
Serum 25-Hydroxyvitamin D Has a Modest Positive Association with Leukocyte Telomere Length in Middle-Aged US Adults. Link to ABSTRACT.