The Amazon Tribe That Ages Slower Than the Rest of the World

In the depths of the Amazon rainforest, the Tsimane community thrives, living in harmony with nature in a way that seems almost untouched by time. Among them is Martina Canchi Nate, whose vigor and strength defy the years stated on her ID card. At 84, she moves through the Bolivian jungle with the grace and energy of someone decades younger. With ease, she digs up yucca trees, slices down plantains, and carries a hefty load of fruit on her back, making her way home from her chaco—the patch of land where she cultivates cassava, corn, plantains, and rice.

Martina is just one of the 16,000 Tsimanes (pronounced “chee-may-nay”) who live deep in the Amazon, about 600km north of La Paz, Bolivia’s largest city. Their vitality is not an anomaly within this community. Scientists have observed that the Tsimanes have the healthiest arteries ever studied, and their brains age more slowly than those in North America, Europe, and other parts of the world.

The Tsimane Community: A Life of Subsistence

The Tsimanes are a semi-nomadic indigenous group, one of the last peoples on Earth to live a fully subsistence lifestyle. They hunt, forage, and farm to meet their daily needs. This lifestyle keeps them constantly active—whether they’re hunting animals, planting crops, or weaving roofs. Unlike industrialized populations, where sedentary activities dominate over half of the daylight hours, less than 10% of the Tsimanes’ time is spent sitting or resting.

Juan, another member of the Tsimane community, embodies this active lifestyle. His hunts often last more than eight hours and cover 18km. He prepares meticulously for these hunts, knowing that his survival depends on his ability to find food in the dense jungle.

The Tsimanes live along the Maniqui River, about 100km by boat from the nearest town. Their isolation has shielded them from many of the modern world’s influences, including processed foods, alcohol, and cigarettes. The simplicity of their diet plays a crucial role in their remarkable health.

The Tsimane Diet: A Key to Longevity

The Tsimanes’ diet is high in fiber and low in fat. Only 14% of their calorie intake comes from fat, compared to 34% in the United States. Their foods are rich in carbohydrates, which comprise 72% of their diet, compared to 52% in the US. Protein comes from the animals they hunt—birds, monkeys, and fish—ensuring a nutritious and sustainable diet. Traditional cooking methods avoid frying, preserving the natural qualities of their food.

This diet is markedly different from the typical Western diet, which is often high in processed foods and unhealthy fats. The Tsimanes’ food choices and their physically demanding lifestyle contribute to their extraordinary health and longevity.

Scientific Discoveries: Health and Aging Among the Tsimanes

Two decades ago, anthropologist Hillard Kaplan of the University of New Mexico, alongside Michael Gurven of the University of California, Santa Barbara, began studying the Tsimane community. They initially focused on the anthropological aspects of Tsimane’s life but soon noticed something extraordinary: the elderly Tsimanes showed few signs of common age-related diseases such as hypertension, diabetes, or heart problems.

Their curiosity led them to collaborate with cardiologist Randall C. Thompson, who had been studying the arteries of ancient mummies. In 2013, Thompson and his team discovered that atherosclerosis—commonly considered a modern disease—was present in mummies from ancient civilizations like the Egyptians and Incas. This finding suggested that artery hardening could be influenced by factors other than just modern lifestyles.

Building on this discovery, Kaplan and Gurven’s team conducted CT scans on 705 Tsimanes over 40, searching for coronary artery calcium (CAC), a marker of clogged arteries and potential heart disease. Their study, published in The Lancet in 2017, revealed that 65% of the Tsimanes over 75 had no CAC. In stark contrast, 80% of Americans of the same age had signs of CAC.

Kaplan summarized these findings succinctly: “A 75-year-old Tsimane’s arteries are more like a 50-year-old American’s arteries.” Further research published in 2023 in Proceedings of the National Academy of Science found that elderly Tsimanes exhibited up to 70% less brain atrophy than in industrialized countries like the UK, Japan, and the US. Remarkably, not a single case of Alzheimer’s disease was found among the Tsimane population.

Cultural Narratives and Aging

Determining the exact ages of the Tsimanes is a complex task. Many of them have not been taught numbers well, and they rely on Christian mission records or the ages of their children to estimate their own. For example, Hilda, who believes she is 81, recently celebrated what her family called her “100th birthday or something like that.”

Juan, who estimates his age to be 78, continues to hunt but admits that his body no longer allows him to venture as far as he once did. “Now, the most difficult thing is my body. I don’t walk far anymore… it will be two days at most,” he says, acknowledging the physical limitations of age. Martina, too, finds the three-hour walk to gather jatata—a plant used for weaving roofs—more challenging as the years go by. Yet, she continues the journey once or twice a month, a testament to her strength.

The Challenges of Health and Mortality

Despite their remarkable health, many Tsimanes do not live to old age. When the study began, the average life expectancy in the community was barely 45 years. Today, it has risen to 50, but childhood mortality remains high. At the clinic where the researchers conduct their studies, Dr. Daniel Eid Rodríguez, a Bolivian doctor and medical coordinator for the research team, hears stories of loss from the elderly women who come for examinations. One woman, counting on her fingers, recalls losing five of her six children. Another lost four out of twelve. These are common stories among the Tsimanes, where childhood diseases and infections are challenging.

The researchers found that nearly all Tsimanes have experienced infections from parasites or worms at some point. These infections have led to high levels of inflammation, which, paradoxically, may contribute to their overall health in old age. The scientists speculate that early exposure to infections, combined with a diet rich in natural foods and constant physical activity, could be key factors in the Tsimanes’ longevity.

Modern Influences and Emerging Health Risks

The Tsimanes’ lifestyle, however, is beginning to change. Juan, who once relied solely on hunting for food, has been unable to catch a large animal in months. The 2023 forest fires that destroyed nearly two million hectares of jungle and forest drove many animals away, leaving him to turn to livestock farming. Juan now raises beef steers, hoping they will provide protein for his family.

Additionally, the introduction of outboard motors on boats, known locally as peque-peque, has made travel to markets easier. This new accessibility has brought processed foods such as sugar, flour, and oil into the Tsimane diet and new health challenges. Dr. Eid notes that rowing, once one of the most physically demanding activities, has decreased significantly. As a result, cases of diabetes and higher cholesterol levels are beginning to emerge, particularly among the younger population.

The Role of Researchers in Healthcare

Over the past two decades, the researchers have studied the Tsimane and worked to improve their access to healthcare. They have facilitated cataract surgeries, treated broken bones, and provided care for snake bites, among other medical needs. While these interventions have improved the quality of life for many Tsimanes, they also highlight the delicate balance between preserving traditional ways of life and embracing modern healthcare.

The Tsimane Perspective on Life and Death

For the Tsimanes, old age is a natural part of life, met with a mix of resilience and acceptance. Hilda, with her infectious laugh, brushes off the thought of death with a simple, “I’m not afraid of dying because they’re going to bury me, and I’m going to stay there… very still.” Her words capture the essence of the Tsimane approach to life—a deep connection to the land, a reliance on community, and a profound acceptance of life’s natural rhythms.

The Tsimanes’ story is one of endurance and adaptability as they navigate the challenges of modern influences while maintaining the traditions that have sustained them for generations. Their hearts may age more slowly, but their spirits remain unyielding, a testament to the power of a life in harmony with nature.