Paris (AFP) - Researchers said Friday they had found an indigenous Amazonian tribe with the lowest levels of artery hardening -- a portender of heart disease -- ever observed.
And while they hailed the group's "subsistence lifestyle" as a heart-protecting factor, others cautioned against romanticising the community's hand-to-mouth existence.
Known as the Tsimane, the small forager-farmer community in Bolivia was five times less likely to develop coronary atherosclerosis (artery hardening) than people in the United States -- where it is a major killer, scientists wrote in The Lancet medical journal.
They pointed to the community's low-fat, high-fibre diet and non-smoking, physically active lifestyle -- factors which most scientists agree contribute to good health.
The study was an observational one, meaning it merely uncovered a correlation between lifestyle and heart health, and cannot conclude that one causes the other.
Yet, "the loss of subsistence diets and lifestyles could be classed as a new risk factor for vascular (blood vessel) ageing," study co-author Hillard Kaplan of the University of New Mexico concluded.
"We believe that components of this way of life could benefit contemporary sedentary populations."
The Tsimane diet comprises unprocessed, high-fibre carbohydrates such as rice, corn, nuts and fruit, as well as wild game and fish.
The community eats little fat, few smoke, and most are active for between four and seven hours a day -- hunting, gathering, fishing and farming, the study found.
Observers pointed out that while the Tsimane had lower levels of artery calcification and heart disease, the most common age of death was 70, compared with about 80 in most developed countries.
And these were just the ones who survive childhood -- one in five die in the first year of life.
"There may not be many old Tsimane men with heart disease but that's probably because only the fittest and healthiest Tsimane survive to old age," commented Gavin Sandercock, a cardiology expert from the University of Essex.
For Tim Chico, a University of Sheffield cardiologist, it is important "not to romanticise" the Tsimane existence.
"Two-thirds of them suffer intestinal worms and they have a very hard life without fresh water sewerage or electricity," he said.
Rates of diseases other than heart disease were much higher in the Tsimane -- especially of the infectious kind.
"So, would I live like the Tsimane to reduce my risk of heart disease? No way," Chico said via the Science Media Centre in London.
Researchers took CT scans of the hearts of 705 adults aged 40-94 in 85 villages in 2014 and 2015 for the study.
Based on the results, they concluded that almost nine in 10 Tsimane people (85 percent) had no risk of heart disease, 13 percent had a low risk, and only three percent a moderate or high risk.
By comparison, about half of Americans aged 45-84 have a moderate or high risk of heart disease.