Bulletproof coffee founder David Asprey visited Tibet in 2009. When he started trekking in Tibet ,his body went through Acute Mountain Sickness. He then tasted yak-butter tea for the first time and he couldn’t stop drinking it. The popular local butter tea transformed him, making him feel almost superhuman. When he returned to the United States, he tried to reproduce what he had back in Tibet. After lots of research, he started experimenting with coffee. Asprey blended low-mold beans with the coconut oil and grass-fed butter, which is higher in omega-3 fatty acid than regular butter. It was delicious. Bulletproof coffee was born.