Issue link: https://bluemagazine.uberflip.com/i/26434
For me it all started in the early '80s on an expedition to La Raya-a town in a valley in the Peruvian Andes, at the great divide of this southern continent. The headwaters of the Amazon flowed in one direction; in the other direction, all waters flowed to Lake Titicaca or on to the Pacific Ocean. Several scientists from the University of British Columbia, including myself, were studying the ecology of the taruca (a high altitude deer). In our search for this swift and beautiful animal at altitudes of over 16,000 feet, I noted that our Peruvian research assistants were always hundreds of meters ahead of us. For them, like the Sherpas, the "thin" air of high altitudes did not seem to be a problem. For us North Americans, it was hugely debilitating. I had spent my life studying how deep-d ivi ng seals and several other ki nds of animals were able to function in situations of low oxygen (or hypoxia). Realizing that humans at high altitude are just another example of this phenomenon (hypoxia adaptation), I set out to discover more. First, we needed proper subject groups. We selected a group of volunteers: Quechuas (descendants of the Incas) from the Andes and Sherpas from the Himalayas. Since the history of high altitude medicine is pep pered with romantic biomedical expeditions to places like Peru, Nepal and Tibet, we chose our subjects from the same region. But we added to our study the possibility of using cut ting-edge technology to analyze their low-oxy gen defense mechanisms. Our subjects would participate in our studies in their home towns as well as travel to the US and Canada for a part of the study. In North America, we evalu ated their metabolic status at rest and during exercise, focusing on several specific tissues including the brain and heart. We found that through generations of I ivi ng at high altitudes, the Quech uas and Sherpas came to express similar biological defense mechanisms against low oxygen. Put simply, people who are indigenous to high alti tude use oxygen with extreme care and effi ciency-getting as much out of each drop of oxygen as possible. We found that the heart, brain and muscle cells of highlanders have a preference toward burn i ng carbohydrates whereas lowlanders have a preference toward burning fatty acids. Burning carbohydrates yields more useful energy per oxygen than burning fat, so native highlanders get more work from the oxygen they inhale in the thin air of high mountains. Another striking thing I discovered abou t the physiologies of Andeans and Himalayans is that they are much more similar