Slowing Down Brain Aging: An Indigenous Group Holds The Key

Findings on slowing down neurodegeneration is much sought after in scientific circles. Recent research shows that an indigenous group from the Bolivian Amazon rainforest may have figured it out for themselves.

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To learn how to slow down the aging process of the brain, scientists have turned to an indigenous group from the Bolivian Amazon. Known as the Tsimane, this group shows incredible retention of brain volume in old age. In all humans, the volume of the brain decreases with age. But the Tsimane people experience significantly slower brain atrophy than people in America and Europe, according to University of Southern California researchers. Accelerated loss of brain volume is associated with numerous neurological disorders, but most namely, dementia.

Despite the Tsimane people having little or no access to modern medical healthcare, they far outdo the Western elderly population’s brain health. This is due to their extremely physically active life and highly nutritious high-fiber whole foods diet of vegetables, fish and lean meat, believe the scientists. 

Conducting this study was no straightforward process. The researchers performed CT scans of the brains of 746 Tsimane adults aged 40 to 94. These participants were provided with transportation from their remote villages in the Amazon to the closest town with CT scanning technology: Trinidad, Bolivia. The journey sometimes lasted as long as two full days, involving travel by both road and river. The scans were used to determine brain volume, with the findings assessed in association with age. Then, the results were compared to three industrialized populations in America and Europe. 

The findings were eye opening. The difference in brain volume between middle age and old age among the Tsimane was found to be a whopping 70% smaller than that seen in Western populations.

Western populations experience much more rapid rates of brain atrophy due to a sedentary lifestyle and a diet rich in sugars and unhealthy fats, say the researchers. These lifestyle patterns make the brain more vulnerable to diseases like Alzheimer’s.

These findings, published in the Journal of Gerontology, Series A: Biological Sciences and Medical Sciences, signify just how integral maintaining a healthy lifestyle consistently over a lifetime can be to overall health in later years. Due to matters of both ethics and feasibility, scientists are unable to conduct large scale, long term experiments weighing the effects of one lifestyle over another in terms of impacts on health. That’s why Andrei Irimia, the lead author behind the study, is calling this “an amazing natural experiment on the potentially detrimental effects of modern lifestyles on our health.”

What does this mean for you?

To slow down brain degeneration and potentially keep neurodegenerative illnesses like dementia and Alzheimer’s at bay, Westerners should take a page out of the Tsimane people’s book. While it may be impossible to lead the exact same lifestyle as this Amazonian indigeous group, we can all stand to be more physically active and eat more nutritious whole foods for the sake of brain health. 

To incorporate the learnings from this study in your life, assess your day-to-day lifestyle by asking yourself the following two questions:


For more on maintaining your healthiest brain, check out:

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