Journal of internal medicine
-
Nutrition profoundly influences the risk for many age-related diseases. Whether nutrition influences human aging biology directly is less clear. Studies in different animal species indicate that reducing food intake ("caloric restriction" [CR]) can increase lifespan and delay the onset of diseases and the biological hallmarks of aging. ⋯ Studies where animals are calorically restricted by providing free access to diluted diets have had less impact on lifespan than those studies where animals are given a reduced aliquot of food each day and are fasting between meals. This has drawn attention to the role of fasting in health and aging, and exploration of the health effects of various fasting regimes. Although definitive human clinical trials of nutrition and aging would need to be unfeasibly long and unrealistically controlled, there is good evidence from animal experiments that some nutritional interventions based on CR, manipulating dietary macronutrients, and fasting can influence aging biology and lifespan.
-
Demographers have studied the Japanese mortality pattern since Japan became the most longevous population worldwide, half a century ago. Nutrition and lifestyle were considered by epidemiologists, gerontologists and other scientists as the most important reasons explaining the Japanese superiority. In Okinawa, the mortality pattern is even more exceptional, but few demographers have pointed out this exception. ⋯ The older generations clearly experience a highly favourable mortality pattern, whereas the younger generations show mortality levels that are definitively higher compared to mainland Japan. This contribution considers which factors may explain such a situation, including the plausible invalidation of the age of some oldest in the population. We plea for in-depth demographic age validation that will enhance all scientific findings so far and boost the exceptional longevity in Okinawa.
-
The current increase in lifespan without an equivalent increase in healthspan poses a grave challenge to the healthcare system and a severe burden on society. However, some individuals seem to be able to live a long and healthy life without the occurrence of major debilitating chronic diseases, and part of this trait seems to be hidden in their genome. ⋯ By combining the results from studies using these different approaches, we conclude that only five main pathways have been consistently linked to longevity, namely (1) insulin/insulin-like growth factor 1 signalling, (2) DNA-damage response and repair, (3) immune function, (4) cholesterol metabolism and (5) telomere maintenance. As our current approaches to study the relevance of these pathways in humans are limited, we suggest that future studies on the genetics of human longevity should focus on the identification and functional characterization of rare genetic variants in genes involved in these pathways.