It is well known that diet and exercise affect health, and research suggestsTrusted Source that it can also affect the speed and progression of aging. Primary aging is the innate process that all people experience; secondary aging is the acceleration of the aging process by excess food intake, lack of exercise, and disease.
It is this secondary aging that may be affected by diet, and studies in animalsTrusted Source have found that restricting calorie intake can slow the process, reduce disease, and prolong life. Although several mechanisms have been proposed to explain this effect, there is no firm evidence showing why caloric restriction might prolong life. Telomeres, aging, and caloric restriction As cells age, telomeresTrusted Source — the protective lengths of DNATrusted Source at the ends of chromosomesTrusted Source — shorten until, eventually, the cell dies. Cell death is a feature of aging so, if cell death was delayed by decreasing the rate at which telomeres shorten, might this delay aging? One studyTrusted Source, in mice, has demonstrated this, showing that caloric restriction slows the shortening of telomeres and prolongs lifespan. Now, researchers from Penn State University have analyzed data from the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIETrusted Source) trial to investigate whether a similar effect might be seen in people. They found that, initially, caloric restriction accelerated telomere shortening, but after a year, it began to slow the process. At the end of 2 years, the calorie restricted and control group had lost similar telomere length. Sebnem Unluisler, chief longevity officer and genetic engineer at the London Regenerative Institute in the United Kingdom, not involved in this research, told Medical News Today: “The study used a method to track changes in telomere length over time with caloric restriction. Initially, those eating less saw faster telomere shortening, but this slowed down later. Surprisingly, after 2 years, both groups showed minimal difference, suggesting a possible plateau effect. This highlights why long-term studies are vital to understand aging-related processes fully.”
Restricting calorie intake in healthy adults