The concept was popularized by Bulletproof Executive founder Dave Asprey, and it took off among Paleo eaters. Integrative physicians like Jeffrey Gladd, MD, now tout its benefits, and healthy celebs like New York chef Seamus Mullen swear by it. “It’s rich and creamy and tastes delicious and gives you tremendous energy for quite a long time. I’ll go pretty much all day on it,” Mullen says. The recipeIt’s not just about the butter. Asprey was initially inspired by yak butter tea, a traditional Tibetan drink, and he set out to create an optimized version. His recipe includes his own “upgraded” coffee beans harvested to reduce the occurrence of mycotoxins (that’s another very long story), unsalted grass-fed butter like Kerrygold (or ghee), and MCT oil, which is extracted from coconut oil to isolate the fatty acids, called medium chain triglycerides. You blend it all together (hello, Nutribullet) into a frothy, latte-like consistency. Tons of Bulletproof-style variations now exist. Many people use their own coffee or coconut oil instead of MCT, since it’s easier to find and much cheaper. Gwyneth Paltrow chef Ariane Resnick doesn’t drink coffee, so she adds the oil and butter to her morning smoothie. The claimsThose who drink it in lieu of a traditional breakfast (yes, it counts as a meal) tend to report serious improvements in energy, focus, and satiety. “When I’ve made it [the drink] with the MCT oil, it was like a kick in the pants in terms of energy,” says the health coach-founder of Stupid Easy Paleo, Stephanie Gaudreau, who usually makes hers with coconut oil. “It’s like rocket fuel!” Dr. Gladd has said it gets him through to lunch without hunger pangs and keeps him focused and sharp at work. Find out the science and the weight loss connection at Well+Good NYC.