A new study finds that measuring the nicotine content in toenail clipping can help predict a woman's risk for heart disease.
Researchers from the University of California, San Diego analyzed the clippings of toenails from more than 62,500 women.
The women in the top fifth for toenail nicotine content were thinner, less active, heavier drinkers, and more likely to have high blood pressure or diabetes, as well as a family history of heart attack, compared to those with less nicotine in their toenails, the study found.
The researchers said the test may be more accurate than asking a person about their smoking history, according to the study, which was published in the American Journal of Epidemiology.
Over the course of the study period, from 1984 to 1998, 905 women were diagnosed with heart disease. On average, the women diagnosed with heart disease had double the nicotine content in their toenails than the women without heart disease.