I love telomeres! And just what are they? They are repetitive DNA sequences at the ends of chromosomes that undergo attrition (shortening) with division of somatic cells. Why is this important? Well, telomeres protect the integrity of the DNA and shortening of telomeres has been associated with the development of chronic diseases and a decreased life expectancy. And so? So telomere length may be our best overall marker for aging. Think of it. How can you measure the “age” of a person? The most obvious is chronologic age but we all know of individuals of the same chronologic age who have aged markedly differently. People of the same chronologic age can look different ages, be of different physical fitness, think with differing clarity, and be of different health. So purely chronologic age is only a relative marker of age. Enter the telomere length. Most obviously telomere length is inversely proportional to chronologic age. But can the attrition of telomeres be otherwise modified and, by inference, lead to a longer, healthier lifespan?
Marta Crous-Bou, a postdoctoral research fellow at the Brigham, published findings in the BMJ examining whether adherence to the Mediterranean diet was associated with longer telomere length. This diet is characterized by a high intake of vegies, fruits, nuts, legumes, grains, and olive oil; a low intake of saturated fats, dairy, meats, and poultry; a moderately high intake of fish; and a regular moderate intake of alcohol (wine with meals). The study was a population-based cohort study consisting of 121,700 women registered in the Nurses’ Health Study prospective cohort established in 1976. There have been biennial health questionnaires, blood sampling of a portion (32,825), and dietary assessments made on a regular basis. Healthy controls consisted of 4,676 members not reporting major chronic diseases.
Not surprisingly, telomere length was inversely related to chronologic age. The key point is that adherence to a Mediterranean-like diet was associated with longer (age-adjusted) telomere length. This association remained after corrections for BMI, smoking, physical activity, and total caloric intake. Additional adjustment for post-menopausal hormone therapy, age at menopause, history of hypertension, socioeconomic status, and case control study batch did not change the estimates. None of the individual components of a Mediterranean diet reached statistical significance.
So there you go. Long live telomeres! Or, is it the other way around?
Marshall Kubota, MD
BMJ 2014, 349.g6674 doi.10.1136/bmj.g6674