Tsimane In Bolivia: Longevity Secrets Revealed

The Tsimane, also known as the Tsimane' or Chimane, are an indigenous people of lowland Bolivia, living in small villages in the Amazon rainforest. They are one of the last peoples on the planet to live a fully subsistence lifestyle of hunting, foraging and farming. The Tsimane have been studied by researchers for their extraordinarily healthy hearts and brains, which appear to age more slowly than those of people in North America, Europe and elsewhere.

The Tsimane's diet

The Tsimane people of Bolivia have been found to have some of the healthiest hearts in the world. Their diet is high in carbohydrates, with a small amount of protein and fat, and very little sugar.

The Tsimane diet consists of complex carbohydrates, including plantains, rice, manioc root, and corn, which make up about 64-72% of their diet. They also consume small amounts of wild game and fish, which provide about 15-21% of their protein intake. Their fat intake is about 15%, and they get most of their fats from the occasional swig of a beer-like drink made from fermenting manioc root.

The Tsimane diet is also very low in processed foods and added sugars. They do not consume large amounts of processed meats, salts, or sugars, which are common in American diets. Instead, the only sugar the Tsimane people eat comes from the small amount of fruit they consume.

The Tsimane diet is also notable for its lack of trans fats, which are artificially created and genetically modified cooking oils found in highly processed foods like cakes, cookies, deep-fried fast food, and margarine.

In addition to their diet, the Tsimane people also lead highly active lifestyles, spending about 90% of their daylight hours in motion. They are constantly hunting, fishing, farming, and foraging for food, which helps them burn off the high number of calories they consume.

Overall, the Tsimane diet and lifestyle have been found to have a positive impact on their heart health, with an 80-year-old Tsimane person having the heart health of an average American in their mid-50s.

Their physical activity

The Tsimane people of Bolivia are known for their active lifestyle, which involves a variety of physical activities such as hunting, fishing, foraging, and farming. They live in small villages, typically consisting of extended family clusters, and their economy is based on small-scale cultivation, hunting, fishing, and gathering wild forest products. This way of life requires a significant amount of physical activity, which has been identified as a key factor in their overall health and longevity.

Hunting is a vital part of Tsimane life, and it requires a considerable amount of physical exertion. The average hunt lasts more than eight hours and covers a distance of 18 kilometres. The Tsimane men use rifles, shotguns, hunting dogs, machetes, and sometimes bows and arrows to hunt a variety of animals, including collared peccary, Brazilian tapir, grey-brocket deer, howler monkeys, agouti paca, white-faced capuchin monkeys, and coati.

Fishing is another important activity for the Tsimane, and they employ various methods to catch fish, including using hooks and lines, bows and arrows, nets, handmade weirs, and poisons during communal barbasco events, especially during the dry season. The Tsimane people also engage in swidden agriculture, cultivating bananas, manioc, corn, rice, and plantains through slash-and-burn farming practices.

The Tsimane people's daily activities result in a high level of physical activity. On average, Tsimane adults walk approximately 16,000 to 17,000 steps per day, which is significantly higher than the average in industrialised countries. This level of physical activity is believed to be a crucial factor in the Tsimane people's heart health and overall well-being.

In addition to their physical activity, the Tsimane diet also plays a role in their health. Their diet consists of approximately 64 percent complex carbohydrates, 21 percent proteins, and 15 percent fats. They consume a variety of foods, including plantains, rice, manioc root, corn, wild game, fish, and fermented drinks. However, they generally do not consume large amounts of processed foods, sugars, or salts, which are common in Western diets.

The active lifestyle of the Tsimane people, combined with their diet, has been linked to their exceptional heart health and slower brain ageing. Studies have shown that they have lower rates of heart disease and healthier arteries compared to Western populations. Additionally, the Tsimane people experience less brain atrophy and a decreased risk of cognitive impairment, functional decline, and dementia.

Their sleep patterns

The Tsimane, an indigenous people of lowland Bolivia, have been studied for their "natural" sleep patterns in nonindustrial or preindustrial societies. Their sleep patterns have been compared to those in industrial societies to assess the relationships between sleep and health.

A typical day for the Tsimane involves working during the day, cooking food, sharing a meal, and then congregating by the fire to share stories as it gets dark. Sleep onset for children and mothers occurs on average 3.3 hours after sunset, while men tend to stay up later. Sleep duration from beginning to end averaged 6.9–8.5 hours, with actual time slept ranging from 5.7–7.1 hours. This is less sleep than what is typically reported in industrial societies.

The Tsimane's sleep patterns show substantial night-to-night variation, with 69% of the total variation in sleep duration attributed to nightly differences within the same individuals. This variation is primarily driven by changes in sleep onset, especially for men, with activities such as hunting, fishing, housework, and watching TV contributing to later bedtimes.

The Tsimane's sleep duration does not vary significantly based on the day of the week, unlike in industrial societies where sleep patterns differ between weekdays and weekends. This may be due to their semi-sedentary lifestyle and lack of rigid work schedules.

The Tsimane's sleep-wake cycles are influenced by factors such as natural light, ambient temperature, and seasonality. Their sleep patterns reflect a balance between the opportunity costs of sleep and nighttime activities, suggesting that they sleep less when opportunity costs are high and make up for lost sleep when those costs are lower.

Overall, the Tsimane's sleep patterns provide valuable insights into "natural" sleep in preindustrial societies and offer a unique perspective on the relationships between sleep, health, and cultural factors.

Their exposure to parasites and pathogens

The Tsimane people of Bolivia have a high exposure to parasites and pathogens. About 70% of the Tsimane have the parasitic worms, Helminths. The most common infections are the hookworm (Ancylostoma duodenale or Necator americanus), found in 56% of the population, and the roundworm (Ascaris lumbricoides) found in 15 to 20% of the population. Protozoan infections are also common, including Giardia lambia (30%) and E. histolytica (5%).

The high prevalence of infection and the shunting of requisite energy toward immune defense may help explain the slow somatic growth and stunting common among the Tsimane, as well as similarly energy-limited populations experiencing high pathogen burden. Population differences in growth trajectories during childhood may reflect patterns of pathogen exposure and immune investment, since Tsimane show slower growth during periods of their early peak IgE production. The higher energetic cost of tolerating and/or defending oneself from parasites may be further offset by other shifts in energy use. Possibilities in the Tsimane context include lower physical activity, sickness behavior, cachexia and osteopenia, dyslipidemia and anemia.

The Tsimane's high parasite burden also affects their fertility. Hookworm reduces fertility, while roundworm may shorten interbirth intervals, perhaps by increasing maternal immunological tolerance of a fetus. The high transmission rate of multiple pathogens in the Tsimane environment also appears to be associated with adaptive and plastic immune responses. The peak shift hypothesis, for example, suggests that peak incidence rates occur at younger ages as immune defenses develop earlier in more infectious environments.

The Tsimane's high parasite burden has also led to a high resting metabolic rate. About 10% to 15% of their metabolism is associated with immune activation.

Their reproductive health

The Tsimane people of Bolivia have a unique approach to reproductive health that is shaped by their traditional lifestyle and the transition towards Western influences. Here is an overview of their reproductive health practices and how they are evolving:

Marriage and Family Planning:

Tsimane culture does not include formal marriage rituals or celebrations. Instead, a couple is considered married if they sleep together under the same roof and are socially recognised as a pair. The median age for first marriages is 21 for males and 16.5 for females. Polygyny, or having multiple wives, is widely accepted, especially in areas influenced by missionaries. However, it is not very common, and sororal polygyny, where a man marries two sisters, is more typical.

Childbearing and Fertility:

Tsimane women have a high fertility rate, with an average of nine children per woman over their lifetime. Inter-birth intervals average approximately two and a half years, and women typically become mothers by age 18. Unfortunately, infant mortality is high, with only about four-fifths of children born surviving to the age of 15.

Contraception and Family Planning:

Traditional Tsimane culture does not include formal family planning methods or contraception. However, recent influences from the outside world may be changing this. The introduction of outboard motors on boats, for example, has reduced the physical activity of rowing, which may impact fertility rates. Additionally, the Tsimane have experienced improvements in healthcare access, including better treatment for broken bones and snake bites.

Reproductive Health Challenges:

The Tsimane face various reproductive health challenges due to their remote location and limited access to modern healthcare. The journey to the nearest hospital in San Borja often requires multiple days of travel, making it impractical for many. While the Bolivian government covers healthcare expenses for pregnant women and infants, the distance and lack of infrastructure present significant challenges.

Infectious Diseases and Parasites:

The Tsimane have high levels of pathogens and inflammation, indicating that their bodies are constantly fighting infections. Additionally, a study found that 70% of Tsimane women were infected with the parasitic roundworm Ascaris lumbricoides, which is believed to increase fertility by suppressing the immune system.

Diet and Nutrition:

The Tsimane diet consists mostly of plants, hunted animals, and fish. They consume high levels of fibre and carbohydrates, with 72% of their calories coming from carbohydrates compared to 52% in the US. Protein sources include birds, monkeys, and fish. The Tsimane do not traditionally fry their food.

Impact of Western Influences:

The Tsimane are gradually adopting Western influences, which is impacting their reproductive health. For example, they are incorporating new foods into their diet, such as sugar, flour, and oil, which may affect fertility and overall health. Additionally, the introduction of modern healthcare and immunisations has led to a decline in infant and elderly mortality rates, improving reproductive health outcomes.

Frequently asked questions