How calorie restriction can extend lifespan -- even If adopted later in life: new study
ScienceDaily — Research is giving scientists new insight into why a restricted diet can lead to a longer lifespan and reduced incidence of age-related diseases for a wide variety of animals. Scientists have known for some time that a restricted diet can extend the lifespan of certain animals but this work shows how it affects ageing mechanisms -- and significantly has also shown that the effects occur even if the restricted diet is adopted later in life. The work could help scientists to better understand, and ultimately, prevent a range of age-related diseases in humans.
The research is being presented at the conference of the British Society for Research on Ageing (BSRA) in Newcastle. It was conducted by scientists at the BBSRC Centre for Integrated Systems Biology of Ageing and Nutrition (CISBAN) at Newcastle University.
Working with the theory that cell senescence -- the point at which a cell can no longer replicate -- is a major cause of ageing the researchers set out to investigate what effect a restricted diet had on this process. By looking at mice fed a restricted diet the team found that they had a reduced accumulation of senescent cells in their livers and intestines. Both organs are known to accumulate large numbers of these cells as animals age.
Alongside this the CISBAN scientists also found that the telomeres of the chromosomes of the mice on restricted diets were better maintained despite their ageing. Telomeres are the protective 'ends' of chromosomes that prevent errors, and therefore diseases, occurring as DNA replicates throughout an organisms lifetime but they are known to become 'eroded' over time.
The adult mice were fed a restricted diet for a short period of time demonstrating that it may not be necessary to follow a very low calorie diet for a lifetime to gain the benefits the scientists found.
Chunfang Wang, the lead researcher on this project at CISBAN, said: "Many people will have heard of the theory that eating a very low calorie diet can help to extend lifespan and there is a lot of evidence that this is true. However, we need a better understanding of what is actually happening in an organism on a restricted diet. Our research, which looked at parts of the body that easily show biological signs of ageing, suggests that a restricted diet can help to reduce the amount of cell senescence occurring and can reduce damage to protective telomeres. In turn this prevents the accumulation of damaging tissue oxidation which would normally lead to age-related disease." Source.