While there has been much study into the effects of a Mediterranean diet on various facets of health, a recent study has now found an association between a Mediterranean diet and telomere length, a biomarker for longevity.
A Mediterranean diet is typically comprised of higher amounts of fruit and vegetables, nuts, legumes, fish, unrefined grains, and olive oil. A Mediterranean diet is also typically lower in saturated fats, dairy products, meat, and poultry. It is typically well-known that a Mediterranean diet is associated with a healthier lifestyle, and studies have consistently demonstrated reduction in mortality, chronic diseases, and cardiovascular diseases linked with a Mediterranean diet.
Some of the current studies that are assessing the health benefits of a Mediterranean diet include:
- Cardiovascular Prevention (Walter Reed National Military Medical Center, Maryland, US)
- Non-Alcoholic Fatty Liver Disease (Harokopio University, Greece)
- Breast Cancer Prevention (TechnischeUniversitaetMuenchen, Germany)
- Cardiovascular Risk Factors (Sapienza University of Rome, Italy)
A recent study reported in the British Medical Journal, however, has assessed the association between a Mediterranean diet and telomere length. Telomeres are, in essence, protective barriers present as repetitive DNA sequences at the ends of chromosomes. Over time, telomeres become shorter, a process that is enhanced by inflammation and oxidative stress. Studies have demonstrated links between telomere length and aging, with a shorter telomere length being linked with a reduction in life expectancy. Telomeres, therefore, are regarded as a biomarker of aging.
The study was based on the notion that telomere deterioration may be modifiable, likely by lifestyle and dietary factors. The study set out to assess the effect of consuming a Mediterranean diet on telomere length. The hypothesis was based on the knowledge that components of the Mediterranean diet (such as fruits, vegetables, and nuts) have demonstrated anti-oxidant and anti-inflammatory activities. Since these factors both have a negative effect on telomere length, the group hypothesised that consuming a diet that reduced these processes would be associated with a longer telomere length.
The study assessed the association between the Mediterranean diet and telomere length in women from the Nurses’ Health Study Cohort in the United States. As a subset of the original cohort, 4676 female registered nurses, from 11 US states, aged between 30 and 55 years at the time of enrolment were included in the study. Dietary intake was assessed by food frequency questionnaires, which included up to 130 different foods.
The study revealed that a greater degree of consumption of foods included in the Mediterranean diet was significantly associated with longer telomere length. The greatest association was visible in women with the highest degree of adherence to a Mediterranean diet. The study reported that the differences seen would correspond to an average of 4.5 years of aging, comparable to difference of 4.6 years seen between smokers and non-smokers.
Clinicaltrials.gov “Mediterranean Lifestyle Intervention in Patients With Non-alcoholic Fatty Liver Disease”Available from: https://www.clinicaltrials.gov/ct2/show/NCT01894438?term=mediterranean+diet&recr=Open&no_unk=Y&rank=7 Last Accessed: Dec 10, 2014.
Clinicaltrials.gov “Feasibility of Lifestyle Intervention in BRCA1/2 Mutation Carriers (LIBRE)”Available from: https://www.clinicaltrials.gov/ct2/show/NCT02087592?term=mediterranean+diet&recr=Open&no_unk=Y&rank=10Last Accessed: Dec 10, 2014.
Clinicaltrials.gov “Cardiovascular Risk Factors, Lipid Metabolism and Oxidative Stress”Available from: https://www.clinicaltrials.gov/ct2/show/NCT01213303?term=mediterranean+diet&recr=Open&no_unk=Y&rank=20Last Accessed: Dec 10, 2014.
Clinicaltrials.gov “Cardiovascular Prevention Program Registry” Available from: https://www.clinicaltrials.gov/ct2/show/NCT01975181?term=mediterranean+diet&recr=Open&no_unk=Y&rank=26Last Accessed: Dec 10, 2014.
Crous-Bou, M, Fung, TT, Prescott, J, Julin, B, Du, M, Sun, Q, Rexrode, KM, Hu, FB, De Vivo, I. “Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study”BMJ 2014;349:g6674
Written by Deborah Tallarigo, PhD