August 3, 2001

Scientists Try to Explain How the Human Body Has Adapted to Living at Extreme Altitudes

By LILA GUTERMAN

Health often plummets when humans ascend to high altitudes. A nasty headache can set in, accompanied by nausea. People complain of dizziness and difficulty sleeping. For 2 in every 10,000 people, the problems can grow far worse. Fluid builds up in the lungs and the brain swells, leading to confusion and even coma.

And yet some 140 million people live at or above 8,000 feet. Those who travel or immigrate to such heights naturally adjust over time to the oxygen-poor environment,