Over a 61-year follow-up of middle-aged men, a Mediterranean diet was shown to decrease risk for many causes of death and reduce total mortality rates. Results of the study were published in the journal Nutrition, Metabolism & Cardiovascular Diseases.
The researchers sought to evaluate, via a posteriori approach, a dietary score obtained from individual data of middle-aged men enrolled in the Italian Rural Areas of the 7 Countries Study of Cardiovascular Diseases in 1960, as well as to examine its association with certain specific causes of mortality until the cohort’s practical extinction. Men from the rural villages of Crevalcore (a province of Bologna in Northern Italy) and Montegiorgio (a province of Ascoli Piceno in Central Italy) aged between 45 and 59 years, who were born or resided in these regions for 5 years or longer, were enrolled in the study. This yielded a total of 1738 individuals who were invited for the entry examination in 1960. Overall, 1712 men participated in the analysis and were followed using several different procedures.
All of the participants’ dietary habits were measured with the use of a dietary history, which was based on a questionnaire that was administered by experienced, supervised technicians. Data obtained were then converted into 18 food groups. Total energy was estimated with the use of local food tables. A factor score was derived from a Principal Component Analysis that was divided into 3 classes: Non-Mediterranean Diet, Intermediate Diet, and Mediterranean Diet.
Follow-up for mortality was extended for 61 years, with dietary habits found to be associated with several different causes of death. Overall, 99.8% of the men died. There were 3 men who were still alive (age range, 102-106 years) and 1 man who was lost when he was alive after 50 years of follow-up (age, 91 years).
Cox proportional hazards models, which were adjusted for 5 major risk factors, demonstrated a significant protective effect of the Mediterranean diet for coronary heart disease (hazard ratio [HR], 0.67), cancer other than that of the lung (HR, 0.74), and other causes as from an operational definition (HR, 0.71), which involved approximately 60% of all deaths. Additionally, the HR for all-cause mortality was 0.85. In contrast, stroke, heart disease of unknown etiology, lung cancer, chronic bronchitis, and unknown causes were not related to participants’ dietary habits.
A major limitation of the study is the small size of the study population and the small number of fatal events that were only partially compensated by the extremely lengthy follow-up observation period. Further, a source of bias might be the absence of women in the analysis.
“Our results might index the role of simple dietary choices that have a profound impact on outcome…and might thus stimulate experimental investigations to be eventually extremely useful for individual dietary selections,” the study authors wrote.
Disclosure: None of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies.
Menotti A, Puddu PE, Catasta G. Dietary habits, cardiovascular and other causes of death in a practically extinct cohort of middle-aged men followed-up for 61 years. Nutr Metab Cardiovasc Dis. Published online april 19, 2022. doi:10.1016/j.numecd.2022.04.010