>>1375413>If you properly acclimatize is it always avoidable aside from the death zone? Or are some people prone to it once they reach a certain height?Both statements are correct. People react differently to high altitudes. For instance, approximately 20% of the population will start experiencing symptoms of acute mountain sickness after rapidy going to 2,500 meters (8,000 ft) and 40% after climbing to 3000 meters (10,000 ft) and so forth. As far as I know, complete acclimatization can always be accomplished (aside from the deaht zone) although it may take some longer to do so than others.