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In the top compartment of my fridge, next to a slightly shrivelled garlic bulb, is a vial of clear liquid. Should I pluck up the courage to inject myself in the stomach every other day, it will reportedly reverse the ageing of my cells, return my metabolism to that of a 20-year-old, improve brain fog and fill me with energy. Oh, and maybe tackle my crow’s feet.
For those who are serious about biohacking their longevity — and their wrinkles — NAD, or nicotinamide adenine dinucleotide, is the latest weapon. “It is an incredible tool when we look at how the body ages,” says Dr Abhinay Settipalli, a longevity and cosmetics doctor who prescribes the latest, at-home injectable version to some of his elite athlete patients, including Premier League footballers. “We find that their endurance is on another level, and they can sprint at maximum speed far longer into the game.”
NAD is a molecule found naturally in all living cells and discovered more than a century ago. But groundbreaking research in 1999 found a connection between the molecule and how it reacts with sirtuins, the so-called “guardians of the genome”. Combined, they have the ability to “delay ageing and maintain a high quality of life”, says Professor Shin-ichiro Imai of Washington University School of Medicine. His research, conducted over 20 years, has shown that increased NAD levels can improve activity levels in geriatric mice, leading to improvements in diabetes and general health. “Step by step we’ve been demonstrating the foundation of NAD biology as an anti-ageing intervention.”
Research from Prof Imai’s lab led to the launch of the first commercial NAD-boosting supplement in Japan in 2008. From 2020, NAD+ (the oxidised form of the molecule) IV drips became popular with influencer and podcaster Joe Rogan and celebrities including Kim Kardashian and Hailey Bieber. Now there is the at-home injectable kit: companies developing them include GP‑founded HUM2N, NAD+ At Home and Inside Out Biotech, which launched its VIVE‑NAD+ in September.
Niki Davis, MD of NAD+ At Home, points to evolving research — including the cellular biologist and longevity expert Dr Sandra Kaufmann — which suggests that injecting pure NAD+ is more effective than swallowing an oral precursor supplement because it “provides an immediate supply of what the body needs in its ready-made active form”. She also cites concerns about the body’s ability to digest the molecule. Yet Dr Settipalli says that “the extremely high dose” in NAD+ IV drips is largely “unnecessary and has the potential to tip the ratio in the wrong direction”. This can result in headaches and nausea. When prescribing injectables, Dr Settipalli still works with each of his patients to figure out individual doses, which are monitored and adjusted. Inappropriate use, he says, can cause similar effects to the IV drips.
The at-home products cost between £195 for two weeks’ supply and up to £395 for two months’. Demand has never been higher: in 2022, the global NAD market was valued at $535.53mn, and is expected to grow to $1.7bn by 2032.
As we age, our NAD levels naturally decrease. This can lead to a sluggish metabolism and wrinkles at best; at worst, obesity and age-related diseases such as Parkinson’s and Alzheimer’s. “By the time we’re 40, NAD levels drop by 50 per cent and continue to decline every decade,” says Rhian Stephenson, a nutritionist and founder of the health brand ARTAH, which offers NAD as a boosting supplement (£60). “Lifestyle factors such as chronic stress, regular alcohol consumption, smoking, lack of exercise, chronic inflammation, poor diet, lack of sleep and excessive food intake can also deplete NAD.” The solution, Professor Imai says, is “to boost NAD levels” — something Stephenson says you will have to do for the rest of your life, although “you may find that you need more or less of it throughout different stages”.
Many people injecting NAD at home report a significant increase in energy. “Immune system, protecting your vital organs — you name it, this is really helping me,” says former cricketer Michael Vaughn in a video promoting NAD+ At Home (he signs off with an energetic “ta-raa”). One medical report notes that an 80-year-old Parkinson’s sufferer’s symptoms improved after three months of NAD+ IV drips. Other claims include significant weight loss and the easing of menopause and long Covid symptoms. One of Dr Settipalli’s more enthusiastic patients reported that taking the injections “is like being on coke”.
Prof Imai is more circumspect about the benefits of NAD injections: his research shows that the “molecule is too big for the cells to incorporate it. It is possible, but it’s not efficient.” He prefers NMN supplements such as those from Japanese brand Mirai Lab (from $227 for 60 capsules) and NMN Bio (£60 for 30 capsules), which boost NAD from inside the cells. Biochemist-turned naturopathic nutritionist Bethany Hughes, co-founder of The Remedy Nutrition Clinic, rates NAD-boosting options for some clients — “most people over 40 would benefit, especially those experiencing cognitive decline” — but cautions against it being used as a miracle cure, advising blood and genetic tests first. “In most cases before prescribing something as specific as NAD, I’d want to know that we were hitting the nail on the head.”
Finally, two weeks after putting my NAD+ At Home in my fridge, I pluck up the courage to use it. I’m not especially scared of needles but I am nervous about injecting myself and getting the amount wrong. In the end, it’s as easy as administering Calpol, although a little more uncomfortable. Measure the amount on the syringe and inject into the tissue below your abdomen.
As for the effects, I felt slightly lightheaded after my first shot, with no desire to sprint down a football pitch. I did, however, sleep incredibly well: my Oura ring reported nearly 30 per cent of REM sleep: my average is under 20. After my second shot, just before a workout, I felt like Hulk Hogan as I powered through my weights set despite a summer heatwave. After a month’s use, my sleep deepened and I felt more peppy. I am not miraculously a stone lighter, however, nor do I look 21. Professor Imai tells me that this is because the results will be taking place on a more cellular level, “such as increasing muscle insulin sensitivity”, which helps with growth and repair. The nearly 60-year-old has naturally jet-black hair. Does he take a supplement every day? “I couldn’t say,” says Imai, grinning.
I confess I’m a sucker for a health fad, but while I’m sold on the long-term benefits of NAD, I’m less keen on the faff of daily injections. As Stephenson says, “Lots of people start with a course of injectables if they’re feeling overly depleted, and then move on to supplementation for maintenance.” If I do live forever, that’s a lot of pills to take.