The highest mountain in the Indian Himalayas is 8586 meters high, at some places vehicles run at 6000 meters. You must visit such high mountains once, this experience will be very special. Watching the setting sun from such a height is very magical. Here in India, most foreigners visit Ladakh which is also called Mars.
The strong sunlight at high altitude burns the skin very fast, I have not suffered anything other than tanning till date, but yes, the air becomes very thin at high altitude due to which vomiting, dizziness, nose bleeding starts. And yes, at high altitude both hunger and thirst disappear.