An isolated tribe in the Bolivian Amazon has been found to have the healthiest arteries of any population ever studied. The Tsimane (pronounced chee-MAH-nay) are a forager-horticulturist tribe that has been found to have extraordinarily low levels of vascular aging, with an 80-year-old Tsimane boasting the same vascular age as an American 25 years their junior.
The observational study comprehensively examined 705 Tsimane adults, including taking CT scans of their hearts to accurately measure the state of their coronary arteries. The CT scan results showed 85 percent of the participants had no risk of heart disease.
Even more compelling were the results focusing on the older Tsimane population, which showed 65 percent of those aged over 75 years old had almost no risk of heart disease, and only 8 percent of that age bracket had a moderate to high risk.
This can be compared to a recent study of heart disease risk in the United States that found 50 percent of people over the age of 45 had a moderate or high risk of heart disease. This is five times higher than the prevalence found in the Tsimane population.
The researchers suggest this dramatic difference is a result of lifestyle rather than genetics, with the study focusing on several dietary and behavioral traits that could be fundamental to the Tsimane people's healthy hearts.
"Their lifestyle suggests that a diet low in saturated fats and high in non-processed fiber-rich carbohydrates, along with wild game and fish, not smoking and being active throughout the day could help prevent hardening in the arteries of the heart," explains senior author of the study, Professor Hillard Kaplan.
As well as spending only 10 percent of their day inactive (contrasted to industrial populations who are classified as inactive for over 50 percent of their waking hours), the Tsimane interestingly consume a largely carbohydrate-based diet. Almost three-quarters of their diet consists of high-fiber foods such as rice, plantain, manioc, corn, nuts and fruits. Only 14 percent of their diet comes from animal meat.
One of the more unexpected results of the study was the discovery that half of the Tsimane population had elevated levels of inflammation, which is commonly thought of as a marker pointing to unhealthy arteries. The study hypothesizes the raised inflammation levels present as the result of higher rates of infections in the population.
The researchers propose several elements of the Tsimane lifestyle could be easily transferable to Western behaviors resulting in lower risks of heart disease. Not smoking, engaging in the more active lifestyle, and eating a diet rich in non-processed foods, are all directions to a healthier life that are not new or surprising. But this study of the Tsimane population is another affirmation that making some simple behavioral changes could dramatically reduce our risk of heart disease.
The team's study published their results in The Lancet.
Source: The Lancet via Alpha Galileo