Cataract surgery is one of the most common operations performed in the U.S. About four million Americans had the surgery last year alone. And now a new study suggests the benefits may go beyond improving vision problems — older women with cataracts who had the surgery actually tended to live longer.

The study, published in JAMA Ophthalmology, looked at data on more than 74,000 women with cataracts, ages 65 and above, and associated the eye procedure with a 60 percent lower risk of dying from all causes. The study does not prove surgery is responsible for their longer lives, but experts see reasons why it might make a difference.

“It’s not so much that cataract surgery does anything to a heart or the brain or the cardiovascular system, but what it does do is it improves quality of life,” said Dr. Christopher Starr, an ophthalmologist at Weill Cornell Medical Center. “By improving quality of life by improving vision, you also can improve quantity of life. You’re living longer. And the theory is that because the vision has improved, you’re more agile, you’re going to trip and fall less. You might be more physically active, might exercise more, you can get to the doctor more often, you can take your medication and see what you’re taking, and more motivation really to live.”

Starr likened cataracts, which he described as “very common,” to a dirty lens on your glasses or camera.

“When we’re born, we have nice clear translucent lenses. As we get older, they get yellower, they get more opaque and less translucent, and therefore the vision gets blurred, and that’s what a cataract is,” Starr said.

Women are more prone to cataracts, according to the National Eye Institute.

“We think it’s post-menopausally, the decrease in estrogen probably leads to the increased risk of cataract. And there is some data that estrogen therapy, after menopause, can actually decrease the risk of cataract. So it’s estrogen. It’s hormonal,” Starr said.

With baby boomers aging, “lots of people need cataract surgery,” Starr said. But just because you have cataracts doesn’t mean surgery is required.

“You can have a mild cataract and still function well and therefore, you can wait on the surgery,” Starr said.

Because the study was based on data from only female patients, the study has its limits and may not be generalizable for males.