Mediterranean diet and longevity


An analysis of the Nurses' Health Study found that those who ate more of a Mediterranean diet had longer telomeres, supporting the health and longevity results from this diet found in other trials (see Mediterranean diet and longevity BMJ 2014 in dropbox, or BMJ 2014;349:g6674). Telomeres undergo attrition with somatic cell division, affecting their ability to prevent loss of genomic DNA at the ends of linear chromosomes, with shorter telomere length considered a biomarker of aging. This attrition is increased with oxidative stress and inflammation, so that age-related attrition rates varies considerably from individual to individual. The interest in this study is that the Mediterranean diet (one rich in vegetables, fruits, nuts, legumes, and unrefined grains; lots of olive oil but low intake of saturated lipids; lots of fish with less meat; and of course moderate intake of alcohol, esp wine at meals) is particularly antioxidant and anti-inflammatory. in brief:

--Nurses' Health Study is prospective cohort study of 121,700 female registered nurses aged 30-55yo, completing biennial questionnaires, including up to 130 food items, beginning in 1976. 32,825 provided blood samples. A Mediterranean diet score was assessed based on the self-assessed dietary questionnaire over time.
--in this nested case-controlled study, 4676 women were selected as healthy controls (free of major diseases). mean age was 59.
--results:
        --they found the expected inverse relationship between age and telomere length (p <0.001). smokers also had shorter telomeres (p=0.02)
        --there was a statistically significant relationship between Mediterranean diet score and telomere length, controlling for BMI, pack years of smoking, physical activity, total caloric intake, postmenopausal hormone therapy, age at menopause, history of hypertension, socioeconomic status.
        ​--the difference in those with high adherence to a Mediterranean diet translated to an average 4.5 years of aging, similar to the difference between smokers and non-smokers (4.6 years) and highly active vs less active women (4.4 years).

so, this result confirms other studies that the Mediterranean diet is a healthy one: in observational and some interventional studies this diet seems to reduce mortality, chronic diseases (especially cardiovascular), and increases the likelihood of healthy aging. in addition, it confirms other studies finding that the rate of attrition of telomeres is modifiable. this study, however, is observational and does not have the rigor of a randomized intervention study. also, they only controlled for certain variables, not including assessments of life stressors (socioeconomic status being a not-so-great surrogate for this), which have been shown to be associated with accelerated telomere shortening. in addition there was only one measurement of telomere length -- the results would have been more impressive if they assessed changes in individual's  telomere length over time and assessed the association with their diet, controlling for the other variables. but, overall, this study is concordant with many others showing the importance of the Mediterranean diet.

Comments

Post a Comment

if you would like to receive the near-daily emails regularly, please email me at gmodest@uphams.org

Popular posts from this blog

cystatin c: better predictor of bad outcomes than creatinine

  another article found significant discordance between creatinine and cystatin C in assessing renal function,  finding that the latter correlated most strongly with both renal and non-renal adverse clinical outcomes (see   ckd cystatin c better than creat AJKD2023  in  dropbox or doi: 10.1053/ j.ajkd.2023.04.002)   Details: -- 158,601 adults who were in the Stockholm Creatinine Measurements (SCREAM) project and had testing of creatinine and cystatin C on the same day during a healthcare encounter, from 2010-2018     -- >400,000 outpatient tests were done for both creatinine and cystatin C levels -- mean age 62, 48% female -- mean eGFR by creatinine (   eGFR cr ) 80; mean eGFR by cystatin C ( eGFR cys  ) 73 -- mean stage of renal insufficiency: 39%  eGFR cr   90+; 38%  eGFR cr  60-89; 12%  eGFR cr  45-59; 7.1%  eGFR cr  30-44; 3.2%  eGFR cr  15-29, 0.7%  eGFR cr ...
Read more

diabetes DPP-4 inhibitors and the risk of heart failure

the FDA just came out with a safety alert about 2 DPP-4 inhibitors and the increased risk of heart failure (released 04/05/2016)(see  http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm494252.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery ​ ). details: --saxagliptin and alogliptin were singled out because of 2 clinical trials in diabetic patients with heart disease. in each trial more patients taking these meds were hospitalized for heart failure vs those on placebo     --in the saxagliptin trial: 3.5% were hospitalized for heart failure (vs 2.8% on placebo). risk factors included prior heart failure or kidney disease     --in the alogliptin trial: 3.9% were hospitalized for heart failure (vs 3.3% on placebo) --recommendation by the FDA:     -- we should consider stopping these drugs if the patient develops heart failure ...
Read more

UPDATE: ASCVD risk factor critique

I decided to do an extensive update of my prior ASCVD (atherosclerotic cardiovascular disease) risk analysis and critique of risk calculators, with much more information about the “non-traditional” risk factors. I felt that there should be more data/clarification, since I think we are really undertreating/not preventing the most common cause of death by relying on the current ASCVD risk calculators   -- Cardiovascular risk models:      -- many of us rely on the various cardiovascular risk models to determine the appropriate approach to patients, and these are often integrated into the electronic medical records      -- these risk models have several very important limitations:          -- they are typically based on community data, eg from the Framingham study etc. But, in clinical practice, we are dealing with the individual and not the community:          ...
Read more