You may have heard that worrying can give you wrinkles, but a new study shows anxiety may actually accelerate aging in people on a molecular level.

Researchers at Brigham and Women's Hospital in Boston looked at blood samples from more than 5,000 women age 42 to 69, who were part of the long-running Nurses' Health Study that examines aging and disease in women.

They were looking for the length of the women's telomeres, DNA-protein molecules that protect the tips of chromosomes within cells, guarding genetic information and stopping them from deteriorating. Studies have shown telomeres may be a predictive marker for aging and longevity.

Participants in the study also answered questionnaires about any phobic symptoms, and found a common form of anxiety known as "phobic anxiety" was associated with shorter telomere length in middle-aged and older women. Phobic anxiety is essentially the feeling of distress that arises when thinking about a fear, such as anxiety felt thinking about going to a crowded place.

People with the highest levels of phobic anxiety were shown to have telomere lengths similar to people who were a full six years older. The findings are published in PLoS One.

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