A team of researchers from the United States and Britain found that the more a person weighs, the older his or her cells appear on a molecular level, with obesity adding the equivalent of nearly nine years of age to a person's body.
Telomeres are the caps at the ends of chromosomes, the molecules that carry genes. Every time a cell divides, telomeres shorten. In the natural aging process, telomeres eventually get so short that cells can no longer divide, and they then die. As more and more cells reach the end of their telomeres and die, the inexorable process produces the effects of aging.
Spector found a direct relationship between body weight and telomere length, with telomere length decreasing with increasing body weight.
The lean women had significantly longer telomeres than the heavy women, whose telomeres were significantly longer than those of the obese women.
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