As if gray hair, brittle bones and wrinkles weren’t bad enough, scientists say that as you age the very DNA in your trillions of cells starts to fray, unravel and disintegrate.
Now there may be something you can do to slow the inevitable: exercise.
A study published Monday hints that fitness buffs appear to have “younger” DNA than the chronically sedentary. The finding could help scientists understand the effects of exercise and aging at a molecular level.
Previous research has shown that being physically active reduces the risk of heart disease, cancer and other diseases, potentially extending longevity.
The study’s authors examined just the ends of DNA strands. Called telomeres, these act something like the plastic caps on shoelaces, preventing the DNA in chromosomes from unraveling.
Previous research has shown that older people have shorter ends than younger folks. Indeed, biologists say they shrink every time a cell divides.
How does this lead to overall decrepitude? Eventually it stops your cells from dividing and replenishing themselves, said Emmanuel Skordalakes, a researcher at the Wistar Institute in Philadelphia.
“When the telomeres become short, then you start cutting into actual chromosomes where there are genes essential for our body,” he said.
To prevent the fraying DNA in all those aging cells from seeding malignant tumors, Skordalakes said, the body turns them dormant. “Your body shuts down more and more cells every day and you become old.” More here.