An international team of researchers has concluded that obesity helps make people age.  But some experts caution more data are needed before a connection can be drawn between overweight and accelerated aging.

The British and American authors of the study report that obesity accelerates the aging process significantly. 

Researchers at St. Thomas Hospital in London and the University of Medicine and Dentistry of New Jersey based their conclusion on a study of over 1,100 women between the ages of 18 and 76, dividing the participants into a lean group and a heavy group.  Researchers analyzed the cells of both groups, and women whose weight fell in between.

The investigators found that the protective tips on the women's DNA strands or chromosomes known as telomeres were significantly shorter in the heaviest women compared to the lightest women by 8.8 years.  They hope telomeres can serve as a sort of yardstick for measuring biological aging.

Toby Andrew is one of the study's co-authors.

"The reason researchers are interested in telomere length is that we're hoping that it will provide a good measure of biological aging,? he said.  ?And we certainly know that it's negatively correlated with age and various age related diseases and risk factors and so on that are associated with poor health.  But it's not at the moment known that it's related to genetics at all. This is just a biological study."

Evan Hadley with the U.S. National Institute on Aging calls the findings interesting, but he says they are by no means conclusive.

"It's analogous to blood pressure,? he said.  ?That is, blood pressure also tends to go up.  It's a reasonable correlation with age.  But you don't usually say somebody with higher blood pressure is older or has aged more than someone without it, although they have more risk for age-related diseases.  And similarly you don't say someone who has gone on hypertensive treatment and gets their blood pressure under control is made younger.  The statements about obesity and telomere length are similar to that.  They have to be taken with a considerable amount of caution and interpretation of that."

The study on obesity and aging is reported in the June 14 issue of the journal The Lancet.