New York, Sep 16 (IANS): Heavy smoking, poor diet and lack of exercise can put you at increased risk of age-related macular degeneration (AMD), especially if you have a family history of the blinding eye disorder, says a new study.

The findings suggest that genetic and lifestyle factors may contribute to AMD in a synergistic way.

"If you have a family history of AMD, the good news is that the study findings suggest that there are things you can do to potentially lower your risk of developing AMD yourself," said one of the lead researchers Julie A Mares from University of Wisconsin-Madison in the US.

The researchers studied the risk among women aged 50 to 79 years. The researchers evaluated the diet and exercise patterns of 1663 women and categorised them into lowest, moderate and highest-risk groups.

They also evaluated whether the women smoked and, if so, how many years they smoked a pack of cigarettes or more each day.

They also assessed genetic data from the women to determine whether they carried known genetic risk factors for AMD.

A total of 337 women in the study developed AMD, of whom 91 percent had early-stage disease.

Among women with stable diets, those who had genetic risk, smoked at least seven pack-years, and were in the highest-risk diet and exercise categories were more than four times more likely to have AMD compared to those women who did not have genetic risk factors and who ate a healthy diet and got at least 10 hours/week of light exercise or at least eight hours of moderate activity such as brisk walking.

The findings were published online in the journal Ophthalmology.