Small wonder the global anti-ageing market was valued at around US$62 billion in 2021, a figure expected to rise to US$93 billion by 2027, and that the NMN market alone is forecast to be worth US$1.19 billion by 2028.

Research on the effects of NMN supplements is under way, but more studies are needed.

Hong Kong-based doctor Laurena Law says companies marketing NMN supplements are able to sell them over the counter and online in Hong Kong as long as they do not make any claims about them treating diseases.

In Australia, where Law trained, NMN supplements are available after a clinical consultation with a health practitioner.

Biotech and pharmaceutical companies have been quick to jump on the NMN bandwagon, some with scant concern for quality control.

Tests conducted earlier this year on more than a dozen commercially available NMN supplements in Singapore found most did not live up to the claims made on their labels.

Many fell far short: three were found to contain no NMN, and six contained between 20 and 99.2 per cent less than they claimed to.

A lot of supplement labels make false claims about ingredients. One study found 89 per cent of labels did not list them accurately and that 12 per cent of products contained ingredients prohibited by medicines regulator the US Food and Drug Administration (FDA).

This is not why the FDA banned NMN as a dietary supplement in the US in December, 2022, however; the agency said claims made about NMN’s ability to treat, mitigate, or prevent diseases were not supported by scientific evidence.

“A product sold as a dietary supplement and represented explicitly or implicitly for treatment, prevention, or cure of a specific disease or class of diseases meets the definition of a drug and is subject to regulation as a drug,” the agency states on its website.

How NMN is believed to work

Dr David Sinclair, a professor of genetics at Harvard Medical School, has researched NMN extensively, studying its potential benefits for longevity, brain and heart health, sleep, diabetes, liver conditions and athletic performance.

In 2013, more than a century after NAD was first identified, Sinclair published a paper in the medical journal Cell revealing his findings that giving old mice NMN treatments to increase their NAD levels helped rejuvenate them.

Within one week of treatment, “key biochemical markers of muscle health” in a 22-month-old mouse were at levels similar to those of a six-month-old mouse.

If NMN is the fuel, NAD is the power; it helps our body to perform at its best. Without it, our body does not function or repair itself as well.

Because NAD supports and accelerates cell repair, it may slow the rate of neurodegeneration. It may even protect against inflammatory diseases such as cancer.

The problem with NAD is that as we age we need more of it to repair cells and incur more DNA damage yet our body actually produces less of it.

Research has shown that NAD levels in humans halve by middle age, which may explain the demand for NMN supplementation.

Nicotinamide riboside, or NR, is a molecule related to NMN and NAD that people also take as an anti-ageing supplement. Studies suggests that the body converts NR into NMN, which is then converted into NAD.

Sinclair has often been quoted as saying that NMN supplements improved his health substantially and that, as a man in his fifties, his biological age was closer to that of a man 20 years younger.

A study published in late 2023 found that, while NMN has potential as an anti-ageing agent, “there are still obstacles that need to be addressed before NMN-containing products can be confidently marketed”.

Law agrees.

“With any dietary supplement, safety, purity and efficacy are important, [and this is] especially [so] in longevity medicine, not only to ensure you’re getting the active ingredient you’re paying good money for, but because some added ingredients can be harmful and can lead to liver dysfunction,” she says.

Law’s advice when buying NMN, and indeed any supplement, is to check for a GMP (Good Manufacturing Practice) label or logo. Alternatively, look for a USP – United States Pharmacopeia – logo. These attest to the quality of the supplement.

“They help ensure the quality of dietary supplements by providing auditing and testing services,” Law says.

In Australia, you can search for a list of approved products on the Therapeutic Goods Administration (TGA) website.

“If supplements containing NMN as a single ingredient have the above verifications, [they are] probably of good quality,” Law says.

Some of the limited research carried out on the effects of NMN supplements on humans suggests it provides benefits such as improving quality of life and physical function in middle age. Law sometimes considers prescribing it for these purposes.

She reminds us that lifestyle choices can slow down ageing too.

To adopt most such measures costs little, if anything.

The challenge is that lifestyle change takes discipline, while taking a pill does not.

“I suppose sensational, extraordinary claims make headlines, but broccoli is boring,” Law says.