March 26, 2009

Women: Stress, weight may shorten life

U.S. researchers suggest low perceived stress and healthy weight may help lengthen women's lives.

Two studies -- both published in Cancer Epidemiology Biomarkers & Prevention and conducted by researchers at the National Institute of Environmental Health Sciences -- examined 647 women enrolled in the long-term Sister Study of 50,000 women ages 34-74 who had sisters with breast cancer.

Both studies looked at telomeres -- DNA sequences that buffer chromosomes against the loss of genes during cell replication -- which shorten with age.

In the first study, women who were overweight before or during their 30s, and maintained that status since those years, had shorter telomeres.

Our results support the hypothesis that obesity accelerates the aging process, study lead author Sangmi Kim said.

In the other study, women who reported stress had somewhat shorter telomeres, but for those who perceived stress and also had elevated stress hormone levels in their urine, the difference was striking.

The difference in telomere length was equivalent to or greater than the effects of being obese, smoking or 10 years of aging, study lead author Christine Parks said in a statement.