SDK1987, to clarify, I think that, by 'bulletproof' people, Gefest000 means specifically the followers of Dave Asprey's low-carb diet that includes so-called 'bulletproof coffee', which is 'a coffee drink with butter and medium-chain triglyceride derived from coconut oil'.
I believe Tim Ferriss (another famous biohacker) more than Dave Asprey, though I'm not a close follower of either, and I can't deny carbs to myself anyway because of mood issues, which means that it's easier for me to eat a slow-carb, low-fat diet than a low-carb, high-fat one. So no, I'm not bulletproof.