Something rather odd happens once you hit a certain age: that curious little list of things — peptides, NAD+, red light therapy, therapeutic plasma exchange — which, only a few years back, sounded like proper magician's wisdom, today? We rub along with them quite happily.

Is it simply us getting older and wondering how to stay healthier for longer? Or is it the not-so-subtle nudge of social media (not me, mind you — but I hear plenty about it, seeing as my husband's forever glued to YouTube videos on the subject)?

Whatever the reason, we aren't here to judge the hype. We are here to find out where these treatments actually come from, whether they are safe, and — most importantly — whether there is any real science behind them. And, thankfully, we won't be doing it alone: we have asked the experts.

I got rather hooked on this topic myself, so I think it is worth saying out loud before we go any further, just in case you assumed otherwise: longevity medicine isn't primarily about racking up extra years on the clock.

Longevity no longer simply means living longer. Among ageing researchers, the focus has shifted to healthspan — the number of years we spend healthy, independent and free from major chronic disease. The change reflects growing evidence: a 2024 study published in JAMA Network Open found that people worldwide spend an average of 9.6 years in poor health before death, leaving a healthspan-lifespan gap of roughly 15% of life.

Another important note: ageing itself is the single biggest risk factor for almost every major cause of death — cardiovascular disease, cancer, dementia, type 2 diabetes, frailty. So if a treatment can slow the biological processes of ageing, or simply delay the onset of these conditions, living longer often follows almost by default. Not because the treatment is chasing extra years, but because it is postponing the very diseases that shorten them.

Sounds as though longevity medicine has already made its case before we have even looked at a single treatment. But surely that is mostly down to genetics? Surprisingly, no. Scientists estimate that only around 20–30% of lifespan is determined by our genes; the remaining 70–80% is shaped by lifestyle, environment and other modifiable factors. In other words, there is far more within our control than many of us realise.

Meaning these longevity treatments might actually come in handy. If they work, of course. And do they?

It turns out longevity is hard to classify as a field. Everything from your Whoop strap to icy cold plunges is quietly filed under the same broad umbrella. But here, we are setting sport and biohacking gadgetry aside and turning our attention to something rather more pharmaceutical: the fancy medications.

A quick apology in advance: if we tried to cover every longevity treatment out there, this would turn into a book rather than an article. So I have narrowed it down to four that are making the biggest noise right now.

Surprise, surprise — the name that dominates every conversation about obesity and weight loss has also quietly wandered into the world of longevity. This, in fact, is exactly why I gave you that rather long-winded breakdown on what longevity actually means at the start. It is about to come in handy.

GLP-1 receptor agonists are a class of drugs that mimic glucagon-like peptide-1, a hormone the gut naturally produces after eating. Originally developed to treat type 2 diabetes, they later earned approval for obesity once researchers noticed they produced substantial, sustained weight loss. So what is the longevity connection? Without targeting ageing directly, GLP-1s reduce many of the very conditions that shorten life: cardiovascular disease, type 2 diabetes, chronic kidney disease, fatty liver disease and sleep apnoea — which lines up rather neatly with the definition of longevity we started with.

Among the therapies currently discussed in longevity medicine, GLP-1s have the strongest body of clinical evidence. A large meta-analysis of cardiovascular outcome trials found that GLP-1 receptor agonists reduced all-cause mortality by 12% in patients with type 2 diabetes. Though an important caveat: there is no clinical trial showing that GLP-1 medications extend lifespan in healthy people, or that they slow biological ageing itself.

Rapamycin wasn't developed with longevity in mind. Discovered in soil bacteria on Rapa Nui (Easter Island) in the 1970s, today it is an FDA-approved immunosuppressant used to prevent organ transplant rejection, treat a rare lung disease and even coat coronary stents. Rather specific jobs, I would say. So what on earth is it doing in a longevity article?

The answer lies in mTOR — one of the body's key nutrient-sensing pathways that regulates cell growth and metabolism. By blocking it, rapamycin appears to slow some of the biological processes associated with ageing. In fact, it is one of the very few drugs to have consistently extended lifespan across multiple animal species.

Humans, however, are another story. The evidence is promising rather than conclusive. The PEARL trial found that a year of intermittent low-dose rapamycin was generally well tolerated and produced modest improvements in ageing-related biomarkers, but it didn't show that people actually live longer.

Curiously, that uncertainty hasn't stopped longevity clinics from embracing it. Low-dose, intermittent rapamycin is already prescribed in many clinics, and a quick online search reveals no shortage of pharmacies and providers offering it at every imaginable price point. That said, "available" shouldn't be confused with "proven". Two important notes:

Now, anyone who is ever dipped a toe into the longevity world will have come across NAD+. It isn’t a medication, but a coenzyme found naturally in every living cell. Day in, day out, it helps convert food into energy, repair DNA, support communication between cells and keep the immune system functioning properly.

The longevity industry's interest comes from one simple observation: NAD+ levels appear to decline with age. Exactly how much, though, remains up for debate. It depends on the tissue being studied and the methods researchers use to measure it. Scientific reviews have found that estimates vary considerably across studies — which, let's be honest, is quite a level of uncertainty to be building a business model on.

Most people don't actually take NAD+ itself. Instead, they take NR or NMN — compounds the body can use to produce more NAD+. Some longevity clinics also offer NAD+ through IV drips.

Is any of this actually proven? Worth splitting into two questions here.

First: can NR and NMN raise NAD+ levels? Yes — and the evidence here is fairly convincing. Randomised human trials show that oral NR can significantly increase NAD-related metabolites in the blood. A well-known 2018 study found that six weeks of NR was well tolerated and successfully boosted NAD+ metabolism in healthy middle-aged and older adults.

Second: does that translate into better health or a longer life? So far, we simply don't know. In one trial involving people with mild cognitive impairment, NAD+ levels increased, but cognitive function didn't improve. Another 2025 study found that eight weeks of NR reduced one Alzheimer's-related blood biomarker, yet again without any measurable improvement in cognition.

Another wizardly name, another treatment generating enormous interest in the longevity world. So what on earth are senolytics?

As we age, some cells stop dividing and functioning properly. But rather than doing the decent thing and dying off, they simply linger. These are senescent cells — or, rather more amusingly, "zombie cells." They no longer do their job, yet continue releasing inflammatory molecules and other troublesome signals that damage nearby healthy cells and contribute to a whole host of age-related diseases.Senolytics are drugs designed to selectively bump off these zombie cells.

Versions of senolytics already exist — some as supplements, others as cancer drugs that have been used for years to treat certain forms of leukaemia. But not a single one is approved by the FDA or EMA specifically for treating ageing.

The research so far is promising, but that is about as far as it goes. Clearing senescent cells has repeatedly extended lifespan in mice. Human studies, however, are still small and early-stage, designed primarily to assess safety rather than whether people actually live longer — and they have been conducted not in healthy volunteers, but in patients with conditions linked to an excess of senescent cells, such as idiopathic pulmonary fibrosis, diabetic kidney disease and Alzheimer's disease.

That hasn't stopped senolytics from becoming commercially available. While some longevity clinics offer protocols combining compounds such as dasatinib and quercetin or fisetin, many of these supplements can also be purchased online with little difficulty. None, however, has been approved specifically for slowing ageing, meaning their use for longevity remains off-label or unproven.

As for safety, the jury is still out. Not every senescent cell is harmful; some play important roles in wound healing and tissue repair, meaning that removing too many — or the wrong ones — could create problems of their own.

There isn't a simple answer to that — and certainly not one I would presume to give. But there are two things worth keeping in mind.

First: tests matter. Really matter. Remember that, years ago, people even used X-rays for cosmetic purposes before it was discovered that they could be seriously harmful — for many, that discovery came too late. So do rely on treatments that have actually been properly tested, not just the ones with the best marketing.

Second: quite apart from all this medical wizardry, there are things with a proven, far more accessible longevity effect — a healthy lifestyle, good sleep, decent food, less stress, and sport. So if you are thinking about starting your own longevity journey, start there. Get those five pillars sorted first, and only then consider the rest, though please only under the guidance of a proper doctor.