Some 55% of consumers who use the devices believe they have gone beyond improving their fitness and also benefited their mental health, with the figure rising to 61% of 16 to 34-year-olds, the study by analysts Mintel indicates.
Meanwhile, 72% of wearable fitness tracker users say their device has helped improve their physical health and 71% say they exercise more often since buying their gadget.
Six in 10 (59%) of those who own the devices use them daily, and 18% use them three to six days a week, the survey found. Just 7% stopped using the gadgets after buying one.
Andrew Moss, technology analyst at Mintel, said: “Wrist-worn technology began with a fitness focus and an emphasis on tracking speed, distance and calories, but now the technology has moved beyond these initial functions.
“While quantifying improvements in this area is difficult, Brits feel strongly that this technology can help improve their mental health. This perception is likely to be the result of an increased focus on physical health amongst device owners, as improvements here can have a knock-on effect on mental health and overall well-being.
“However, these devices also offer more concrete benefits by allowing users to track sleep and stress levels, and by supporting participation in mindfulness and calming exercises.”
Just under one in five Britons (18%) now owns a fitness band or sports watch, up from 14% in June last year, with ownership peaking among consumers aged 25 to 34.
About 11% own a smartwatch, up from 9% in June 2017, although men are almost twice as likely as women to wear one.
Mintel forecasts that sales of wrist-worn devices will hit 4.2 million this year, up from just under four million last year.
Mintel surveyed 2,000 internet users aged 16 and over in September.