Green tea contains certain antioxidant chemicals that may help ward off the body-cell damage that can lead to disease. Now a large study of Japanese adults suggests older people who regularly drink the beverage may stay more agile and independent than their peers over time.

While many researchers in recent years have studied green tea’s effects on everything from cholesterol to the risk of certain cancers, results have so far been mixed. But in a new study published in the American Journal of Clinical Nutrition, Japanese researchers focused on whether or not green-tea drinkers have any lower risk of frailty and disability as they grow old.

They followed nearly 14,000 adults age 65 and older and found that in the three years that followed, people who drank the most green tea were the least likely to develop “functional disability” — defined as problems with daily activities like shopping or doing housework, or difficulty with more basic needs like dressing and bathing themselves.

Almost 13 percent of adults in the study who drank less than a cup of green tea per day became functionally disabled, compared with just over 7 percent of people who drank at least five cups per day.

Researchers point out green-tea lovers tend to have healthier diets overall, more education, lower smoking rates, fewer heart attacks and strokes and greater mental sharpness. In addition, they were more socially active, and since studies have found older adults with more “social support” are less likely to become disabled, that could be an important factor.

But according to the researchers, led by Yasutake Tomata of Tohoku University Graduate School of Medicine, even with those factors considered, green tea itself was tied to a lower disability risk.

In particular, people who drank at least five cups a day were one-third less likely to develop disabilities than those who had less than a cup a day. Those who averaged three or four cups a day had a 25 percent lower risk, which could very well mean green tea has a real effect.

But ultimately, Tomata’s team writes, definitive proof can come only from clinical trials testing the effects of green tea, or green tea extracts, on disability risk. And before you start downing gallons of the stuff, keep in mind green tea contains small amounts of caffeine and vitamin K, meaning it could interfere with drugs — so if you’re on medications, talk to your doctor first.