TWO indigenous groups in the Amazon have been found to have a dementia rate of 1%, compared to 8% to 11% in developed countries. According to specialists, their way of life and air quality may explain these findings.

Do indigenous people in the Bolivian Amazon hold the secret to keeping dementia at bay?

The results of a study published in the Journal of the Alzheimer's Association suggest that this could be the case. Two groups, the Tsimane and the Mosetén people, were found to have a 1% rate of dementia among people over 65. In developed countries, this rate is between 8% and 11%.

To carry out their research, scientists from the University of Southern California in Los Angeles evaluated the mental state of indigenous people over 60 years old in the two groups.

A Bolivian physician, already familiar with the groups, asked them a series of questions. The health of the respondents' brains was measured by several neurological assessments, including brain scans, cognitive tests and a questionnaire.

Among the Tsimane people, who number about 17,000, the scientists were able to study 435 volunteers, of whom five suffered from dementia. Among the Moseten people, who total approximately 3,000 individuals, 169 members were assessed, with only one case of dementia.


A diet low in saturated fats

"Indigenous Tsimane and Moseten have a low prevalence of Alzheimer's disease and related dementias," reads the study.

"Something about the pre-industrial subsistence lifestyle appears to protect older Tsimane and Moseten from dementia," explains Margaret Gatz, the lead study author and professor of psychology, gerontology and preventive medicine at the University of Southern California.

According to the specialists, the answer lies in the lifestyle of these tribes, whose diet is low in saturated fat and whose lifestyle is "physically demanding."

This could contribute to staving off Alzheimer's disease, the development of which can be associated with various factors, such as high blood pressure, cardiovascular disease, physical inactivity and air pollution.

The benefits of this lifestyle do not stop there, according to previous studies, members of these two groups, located in the Amazon region, have the healthiest hearts in the world.

In addition, their brain aging has been found to be 70% slower than for Westerners.