The findings are based on tracking the cardiovascular health and death rates of 1150 inhabitants of three villages not far from Athens, Greece, for a period of 15 years.
In Greece, deaths from heart disease and all causes are among the lowest of any developed country.
One of the villages is located in a mountainous area almost 1000 metres above sea level; the other two are located on the plains. But the principal livelihoods in all three villages are similar - farming and animal husbandry for the men and home making for the women.
Information on risk factors, including gender, age, weight, smoking habit, blood pressure, and alcohol consumption, were collected for each person in 1981. Blood samples were also taken to build up the profile of biochemical health.
Overall, both men and women living in the mountain village had a worse coronary heart disease risk profile than their peers living in the lowland area, with higher rates of circulating blood lipids and higher blood pressure.
In 1996 the researchers assessed the number of survivors. Over the 15 years, 150 men and 140 women died. Of these, 67 deaths, 34 of which were among the men, were attributable to coronary heart disease.
But after taking account of all the cardiovascular risk factors, mountain village residents had lower death rates, and lower rates of death from heart disease, than their peers in the lowlands. The effects were more pronounced among the men.
The researchers conclude that as blood lipids and blood pressure were higher among the mountain residents, other 'protective' factors must be at play.
They point out that living at moderately high altitude produces long term physiological changes in the body to enable it to cope with lower levels of oxygen, and that this, combined with the exertion required to walk uphill regularly on rugged terrain, could give the heart a better work-out.