The benefits are wide ranging, and what is more, members find it relatively easy to stick with this type of exercise regime, researchers said.
The findings prompt the researchers to suggest that doctors and other health-care professionals should recommend joining a walking group as a way of boosting health.
Researchers at the University of East Anglia in UK assessed the available evidence from a wide range of sources on the physical and mental health consequences of joining an outdoor walking group for adults, and published up to the end of 2013.
The studies involved participants from 14 different countries, with a wide range of long term conditions, including arthritis, dementia, diabetes, fibromyalgia, obesity/overweight, mental health issues, and Parkinson's disease.
Also Read
Analysis of the pooled data showed that walking groups have wide ranging benefits, above and beyond making people more physically active, researchers found.
People who joined these groups registered statistically significant falls in average blood pressure, resting heart rate, body fat, weight, and total cholesterol.
But walkers also experienced improvements in lung power, overall physical functioning, and general fitness, and they were less depressed than before they started walking regularly.
Three quarters of all the participants stuck with the group, and there were few side effects to speak of, apart from a handful of falls on roots or wet ground.
"Walking groups are effective and safe with good adherence and wide ranging health benefits," they wrote.
"They could be a promising intervention as an adjunct to other health-care, or as a proactive health-promoting activity," said.
The study was published in the British Journal of Sports Medicine.