Peter Attia's personal experiment with tirzepatide resulted in a decrease in his insulin levels to 5.0, an A1C reduction from 5.4-5.5 to 5.0, a slight weight loss of 6-7 pounds, and no loss of muscle mass due to concurrent exercise.

“My A1C has gone from 5.4 5.5 to 5.0. Yep. And my insulin is down to 5.0 as well. So, and did you lose any weight? I lost a little bit of weight. Not a huge amount, six or seven pounds, which was never the goal not to start with. It was the whole idea was and and no loss of muscle mass which actually is the big uh the big um booaboo that you know people will have you fear no loss of muscle mass if you are exercising if you are so for me it's an experiment it's not I haven't decided this is something I'm going to continue but I just wanted to really experiment for myself to try to see okay what is this drug really doing”