NAD boosters: Kendall Jenner and Hailey Bieber are into them, but do they actually stop ageing? | Antiviral

The fountain of youth is an enduring legend. Different iterations of the fabled spring – which is said to give anyone who drinks or bathes in its waters the power to defy ageing – have echoed across cultures for thousands of years.

In the modern age, this quest for youthfulness is known as “biohacking” – where individuals take a do-it-yourself approach to enhance their biology, often through supplements – and the latest trend is NAD boosters.

Ever since Kendall Jenner and Hailey Bieber took IV drips with NAD in an episode of The Kardashians, influencers on TikTok and Instagram have followed suit, telling their followers NAD boosters will “literally give you the fountain of youth … you will stop ageing in its tracks”, in addition to other claimed benefits such as boosting energy and improving hair, skin and metabolic function.

But do any of these claims stack up or are we still in the realm of myth?

What is NAD?

NAD (also referred to as NAD+ and short for nicotinamide adenine dinucleotide) is a naturally occurring molecule involved in more than 500 different reactions in the body, including energy generation, explains Prof Nigel Turner, the head of the Cellular Bioenergetics Laboratory at the Victor Chang Cardiac Research Institute.

More recently – in the last 25 years – it has become apparent the molecule also has really critical functions in ageing, Turner says.

“The whole hype around the NAD boosting therapies is the fact that there’s pretty good scientific evidence that as we age … the levels of NAD decline, and so the efficiency of all these pathways and reactions within the body declines, because the levels naturally drop with ageing,” Turner says.

What does the evidence say?

NAD boosting therapies have been marketed in the form of pills, shots and IV infusions. They are selling manufactured supplements of the nicotinamide precursor compounds that can be converted into NAD. The two primary versions marketed are nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR).

Prof David Vaux, a molecular biologist and honorary fellow of the Walter and Eliza Hall Institute, said while a number of labs are promoting them as treatments for ageing, “in my opinion, it’s way too early. I haven’t seen convincing evidence that they prolong life span 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.”

Turner says while studies in mice and pre-clinical models have shown the replenishment of NAD is associated with changes in the way cells function, better metabolic health and some anti-ageing effects, the evidence of the translation of that research into humans is in its infancy.

“What comes through in the limited amount of studies that have been done in humans, is that it appears that giving these supplements to already healthy or relatively healthy people is not going to do too much because your body’s already got enough.”

However, of the already limited studies, those that have shown some benefits tend to be in overweight and older populations, where the NAD levels may be compromised a bit more, he says.

What’s Vegemite got to do with it?

The body already has a series of pathways that allow for the constant maintenance or replenishment of the NAD that’s being broken down all the time, including through our diets, Turner says.

Vitamin B, specifically vitamin B3 (which is found in Vegemite, among other food sources) is also a precursor, one of these pathways that eventually lead to the formation of NAD, he says.

What do the experts think?

Vaux stresses that the Therapeutic Goods Administration has two kinds of approval: medicines are either registered (when a drug is proved to be effective for treating certain conditions) or they are listed (which means it is safe but there is no evidence it works). Only the second kind of TGA approval has been given for any NAD boosters, he says, “but the people marketing them don’t make that distinction. They just say ‘approved by the TGA’ and trick people into thinking that they actually work.”

A/Prof Lindsay Wu runs the Laboratory for Ageing Research at the University of New South Wales. Wu is also the founder of a company developing NAD precursors and trying to establish efficacy for specific conditions and diseases, as well as safety.

“We don’t yet have that data, whether there is truly these massive effects,” Wu says. However, “a lot of the people who are taking these NAD precursors are in fact young, healthy people [or] middle-aged people. The whole concept of doing this is to replace NAD levels when they get low – but fit healthy people don’t need this … Their NAD levels are already going to be very high.”

Eating a healthy diet and doing exercise have been associated with boosting NAD levels, Turner says. However, he stresses that the best evidence for promoting longevity comes back to a healthy lifestyle, including not smoking or drinking excessively.

“People seem to want to be able to do all of those things and then just take a pill that will overcome it,” he says.

“I still hold great hope that [NAD is] going to be a pathway that will have some benefit, but it’s not going to meet the claims that you see online. It’s not going to take a person who’s got grey hair and turns them back into a 20-year-old.”

• Natasha May is Guardian Australia’s health reporter

• Antiviral is a fortnightly column that interrogates the evidence behind the health headlines and factchecks popular wellness claims