The death of a young woman injected with NAD+ by an unlicensed doctor in the Bronx to which she’d entrusted her care is shining a light on the celebrity-favored boosting therapy.

Assistant District Attorney Ethan Reisbaum said in Bronx Criminal Court early Tuesday that Elizabeth Baron, 27, “immediately went into cardiac arrest and later was pronounced dead” Sunday after receiving an injection of Nicotinamide adenine dinucleotide at Luis Rojas Cabrera’s Bereshit Lifestyle Center in Riverdale.

It is unclear at this time whether NAD+ caused Baron’s death, as autopsy and toxicology results from the Office of the Chief Medical Examiner are pending.

Cabrera, 55, who billed himself as a “M.D., Surgeon, Naturopath,” is facing charges of reckless endangerment and unauthorized practice of a profession. He’s been released without bail.

So what is NAD+, and who buys into the youthful glow it claims to promise?

What is NAD or NAD+?

Levels of NAD+, which is produced by the body and crucial to cellular metabolism, “is a feature of aging and may play a role in the process,” according to one 2021 study by molecular biologist Nichola J. Conlon.

The properties of NAD+ aren’t limited to those in the human body, but “chronically low NAD+” has been “linked to multiple hallmarks of aging” and found in “accelerated aging disorders and age-related disease states,” the paper adds. However, it’s worth noting that its author is the CEO and founder of Nuchido Laboratories, which focuses on aging and sells an NAD+ supplement claiming to “reduce biological age.”

“I haven’t seen convincing evidence that they prolong lifespan in animal models, and I certainly wouldn’t take any myself until they’d been proven to work, be safe and efficacious in a properly run, double-blind, placebo-controlled human trial,” David Vaux, a professor and molecular biologist, told the Guardian in 2025.

“Giving these supplements to already healthy or relatively healthy people is not going to do too much because your body’s already got enough,” Nigel Turner, a professor who heads up the Victor Chang Cardiac Research Institute’s Cellular Bioenergetics Laboratory, told the outlet.

Both Vaux and Turner pointed to the “limited” human studies, despite some promising findings in mice and preclinical models.

Which famous faces have bought in, or at least claimed to?

Kendall Jenner and Hailey Bieber extolled NAD boosters in a May 2022 episode of Hulu’s “The Kardashians,” during the show’s inaugural season. The supermodels received the substance through IV drips, though they’re also available in pill-form and injections, with self-proclaimed hypochondriac Jenner, now 30, saying IV therapy “comfort[s] me.”

Bieber, now 29, joked at the time she intended to continue NAD for the rest of her days. “And I’m never going to age.”

Also in the bag for NAD+ are neuroscientist and podcaster Andrew Huberman, as well as “biohackers” Bryan Johnson and Gary Brecka.