Deep inside the Amazon rainforest scientists uncover the keys to longer living: 'We found zero cases of Alzheimer's. It is remarkable'

An indigenous tribe in the heart of the Bolivian jungle may hold clues to longevity as scientists claim they are the healthiest humans ever studied.

The Tsimane community is one of the last groups of people on the planet to live a fully subsistence lifestyle of hunting, foraging and farming. Less than 10 percent of their daylight hours are spent in sedentary activities, compared to 54 percent in industrious populations and they have little access to processed foods, alcohol and cigarettes.

For decades, scientists have marveled at the astonishing heart and brain health of the Tsimane tribe, rooted deep in the Amazon rainforest, 600km north of La Paz - Bolivia's largest city.

There have been zero cases of Alzheimer's among the tribe's 16,000-strong population while studies show elderly members of the group have 70 percent less brain atrophy than those of the same age in industrialized countries. 

Bolivian doctor Daniel Eid Rodríguez, a medical coordinator for the researchers, told the BBC: 'We found zero cases of Alzheimer's among the entire adult population - it is remarkable,'

The farmer-forager community Tsimane (pictured) from lowland Bolivia were once said to have the 'healthiest hearts ever studied'

A team of researchers led by anthropologist Hillard Kaplan of the University of New Mexico have studied the tribe for two decades.

They found the Tsimanes are constantly kept active by hunting animals, planting food and weaving roofs. 

An average hunt for the tribe lasts more than eight hours and covers 11 miles.

Meanwhile only 14 percent of the calories they consume are from fat, compared to 34 percent in the US, according to the research cited by the BBC. 

Their diets are also high in fiber and 72 percent of their calories come from carbohydrates - compared to 52 percent in the US. 

What's more, their protein is usually sourced from the animals they hunt such as birds, monkeys and fish and their cooking styles does not include frying.

Such lifestyle habits could be the key for longer living in Western societies, scientists have concluded. 

Typically, humans build up fats, cholesterol and other substances that can make their arteries thicken or harden as they age, causing atherosclerosis. 

The hunter-gatherer Tsimane and Moseten communities in the Bolivian Amazon have dementia rates that are 11 times lower than in the US, one study claims

The Tsimane is a tribe of around 16,000 people living along the banks of the Maniqui River in the Bolivian Amazon

But a study published by The Lancet in 2017 found 65 percent of 705 Tsimanes over the age of 40 had coronary artery calcium (CAC) - a sign of clogged-up blood vessels leaving sufferers at risk of a heart attack.

By comparison, 80 percent of Americans show signs of CAC. 

Professor Kaplan concluded: 'A 75-year-old Tsimane's arteries are more like a 50-year-old American's arteries.' 

However, the research is in part limited by the fact Tsimanes do not track their ages as many have difficulty counting. 

The scientists often use the ages of their children to calculate records for the tribe member.

A 78-year-old Tsimane caled Juan told the BBC: 'Now the most difficult thing is my body. I don’t walk far any more… it will be two days at most.'

Despite their remarkable brain and heart health, the Tsimane population has a low life expectancy due to other threats from their environment.

When Professor Kaplan's study began, their life expectancy was barely 45 years old but it has since risen to 50. 

The tribe of more than 16,000 are extremely active in their day-to-day lives with hunting and fishing, and eat a diet low in fats and sugars. Pictured: A Tsimane child climbs a tree in search of a coconut

Dr Eid told the BBC: 'These people who reach the age of 80 were the ones who managed to survive a childhood full of diseases and infections.'

Tribe members were shown to have high levels of pathogens and inflammation which imply they are constantly fighting infections.

It has prompted speculation that this constant exposure to infection could also boost their health long-term.

However, some aspects of the Tsimanes' lifestyles are changing. Multiple forest fires in the region in 2023 demolished almost two million hectares of jungle and forest which caused animals to leave.

It has made hunting in the region more difficult, the BBC reports. 

The tribe is also starting to use boats with an outboard motor which means they are rowing less than before - one of the most strenuous activities they were used to.

Tsimane Hilda, who is said to be 81 according to records, told the outlet: 'I'm not afraid of dying because they're going to bury me and I'm going to stay there… very still.'