But Johnson’s latest escapade went seriously wrong.

Johnson posted to his Instagram on November 14 a jarring close-up of his face, bloated and red, after an attempt to inject a “donor’s” fat into his face to attain a more youthful look.

The idea came as a result of Johnson’s weight loss from his strict 1,950-calorie diet.

“I got really lean and lost a lot of fat—especially in my face. My biomarkers were improving, but I looked gaunt,” Johnson wrote in his caption. “People thought I was on the brink of death.”

That’s what prompted him to initiate what he called, “Project Baby Face,” an attempt to bring youthfulness back into his face.

“Facial fat, we discovered, is pretty important for how people perceive youth,” Johnson wrote. “It didn’t matter how good my biomarkers were if I didn’t have face fat.”

Johnson says he didn’t have enough fat on his own body to inject into his face, hence the need for a donor. His body quickly rejected the fat, though.

“Immediately following the injections, my face began to blow up. And then it got worse, and worse, and worse until I couldn’t even see,” Johnson’s caption says. “It was a severe allergic reaction.”

That complicated his plans for the rest of the day. With a swollen face, Johnson went to his scheduled meeting 30 minutes later with a Bloomberg reporter, warning him that he “might not recognize” Johnson.

Seven days later, Johnson’s face was back to normal, he says. “And we were back in the trenches reformulating plans for our next attempt,” he wrote.

Johnson’s longevity efforts under his Project Blueprint have included receiving blood transfusions from his teenage son—with the idea that this “young blood” procedure (which is not FDA approved) will help reverse aging, adhering to a rigid diet which includes a slew of Blueprint-branded supplements, and undergoing regular gene therapy injections.