why do Tibetans not suffer from altitude sickness?
Tibetans, like other populations living in high-altitude regions, have adapted to their environment over generations. They have developed certain genetic and physiological adaptations that help them cope with the low oxygen levels found at high altitudes. These adaptations make them less susceptible to altitude sickness compared to people from lower-altitude regions who are not acclimated.
One of the key genetic adaptations found in Tibetans is related to the production of hemoglobin, a protein in red blood cells that carries oxygen. Tibetans have a genetic variant in a gene called EPAS1, which regulates the production of hemoglobin. This variant allows Tibetans to produce less hemoglobin in response to low oxygen levels, which helps prevent the blood from becoming too thick and reduces the risk of altitude-related complications.
Tibetans also have other physiological adaptations, such as larger lung volumes and more efficient oxygen utilization, which help them extract and utilize oxygen more effectively at high altitudes. Additionally, they have higher levels of nitric oxide, a molecule that helps dilate blood vessels and improve blood flow, which can further aid in oxygen delivery.
It’s important to note that while Tibetans have a lower prevalence of altitude sickness compared to non-acclimated individuals, they are not completely immune to its effects. Altitude sickness can still occur in Tibetans, especially in those who are not acclimated or have traveled from lower-altitude regions.
Overall, the ability of Tibetans to live at high altitudes with reduced susceptibility to altitude sickness is the result of a combination of genetic and physiological adaptations that have developed over many generations of living in the challenging high-altitude environment of the Tibetan Plateau.