The Best and Latest Supplements in Science for Staying Young

Every generation has wanted to know how to age better. Supplements sit at the centre of that conversation today, but the obsession is far older. Ancient Egyptians sought eternal youth through sacred oils and rituals. Renaissance alchemists chased the mythical Philosopher's Stone. The obsession with defying time is as old as time itself. Now, Silicon Valley billionaires fund longevity research and biohackers stock their shelves with supplements. The quest hasn't faded. It has simply put on a lab coat.

Over the past decade, ageing has been reframed in laboratories around the world. It is no longer viewed solely as the inevitable march of time but, increasingly, as a biological process; one with identifiable drivers, measurable biomarkers, and, in theory, addressable mechanisms. A landmark paper published in the journal Cell in 2013, and significantly updated in 2023, laid out what researchers now call the Hallmarks of Ageing: twelve distinct cellular and molecular processes that, when they go wrong, appear to underpin the physical decline associated with growing older. ¹

The 2023 Cell paper, authored by Carlos López-Otín and colleagues, expanded the original nine hallmarks to twelve, adding disabled macroautophagy, chronic inflammation, and dysbiosis (disruption of the gut microbiome) to the list. ¹

That list is organised across three tiers: the damage that accumulates within individual cells, such as genomic instability and the gradual erosion of telomeres; the cellular responses to that damage, including mitochondrial dysfunction and the build-up of senescent "zombie" cells; and the whole-body effects that follow, from chronic inflammation to the exhaustion of stem cell populations. Together they represent not a catalogue of misfortune, but a roadmap for understanding, and potentially intervening in, the biological machinery that determines how well we age, whether through medical breakthroughs, lifestyle changes, or the growing arsenal of supplements that promise to target these very mechanisms.

What makes this framework scientifically compelling is not just its descriptive power but its prescriptive implications. Each hallmark represents a potential lever. Some of those levers, senolytic supplements that clear zombie cells, interventions that restore mitochondrial function, compounds that activate autophagy, are now being actively studied in clinical trials. Others are already the subject of a quieter, more consumer-facing investigation: the field of longevity supplementation.

This is not the world of multivitamins and vague wellness claims. The most serious work in this space targets the hallmarks directly; molecules that have been shown, in peer-reviewed studies, to interact with the cellular machinery of ageing.

The three tiers of the hallmarks framework, cell damage, cellular response, and whole-body effects, suggest a corresponding logic for supplementation: address the damage at its source, support the cell's ability to respond to it, and protect the systemic environment in which cells must function. The six supplements below map onto that structure. Each targets a distinct cluster of hallmarks. Together, they represent a reasonably coherent biological strategy for supporting healthspan across multiple fronts.

At the centre of cellular energy metabolism sits a molecule called NAD+, nicotinamide adenine dinucleotide. It is involved in hundreds of enzymatic reactions and is essential for the function of sirtuins, a family of proteins that regulate everything from DNA repair to mitochondrial health to inflammatory signalling. In short, NAD+ is foundational to the biology of ageing. ³

The problem is that it declines, significantly, as we age. By middle age, NAD+ levels in many tissues have fallen to roughly half of what they were in early adulthood. This decline is now understood to be implicated in mitochondrial dysfunction, impaired DNA repair, and reduced metabolic efficiency: three of the twelve hallmarks in a single molecular drop. [Alpay, et al.]

Nicotinamide mononucleotide (NMN) is a direct precursor to NAD+. When taken orally, it enters cells and is converted into NAD+, effectively replenishing the supply. The evidence base for this conversion is solid: multiple human clinical trials have confirmed that NMN supplementation raises blood NAD+ levels. A 2024 randomised, placebo-controlled study in healthy older adults found that twelve weeks of NMN supplementation was associated with improved walking speed and better sleep quality compared to placebo; both meaningful functional markers of healthspan. ⁴ A systematic review published in Frontiers in Pharmacology the same year found consistent evidence that NMN supports metabolic function, including improvements in insulin sensitivity. ⁵

The key is not simply topping up NAD+ but sustaining it. NMN raises the level; other compounds help protect it from degradation. One of those is apigenin, a flavonoid found naturally in parsley and chamomile, which inhibits an enzyme called CD38 that consumes NAD+. ⁶ Pterostilbene, a polyphenol related to resveratrol but with better bioavailability, activates sirtuin pathways that make more effective use of the NAD+ that is present. ⁷ Together, the three compounds, NMN, apigenin, and pterostilbene, function as a system rather than a single ingredient.

For Youth's The Repair is built around exactly this logic. It combines 450mg of Uthever® NMN, a pharmaceutical-grade, stability-tested form, with 50mg of ApiAge® Apigenin and 50mg of Trans-Pterostilbene. The formulation, developed by Dr Jan Gruber and Dr Vincenzo Sorrentino of the National University of Singapore, is designed to raise NAD+ levels, protect them, and activate the downstream pathways that make the molecule useful.

The 2023 hallmarks update elevated disabled autophagy to a standalone hallmark of its own. Autophagy is the cell's internal housekeeping process: it identifies damaged proteins, dysfunctional organelles, and other debris, dismantles them, and recycles their components. When it slows down, that accumulation becomes one of the measurable drivers of ageing. The most powerful triggers of autophagy are caloric restriction and fasting. ¹⁶ And, as a major 2024 study in Nature Cell Biology demonstrated, spermidine is the molecular mechanism that makes both work — blocking its synthesis eliminated the longevity benefits of fasting across multiple organisms. ¹⁷ A fifteen-year epidemiological study of 829 participants separately found that higher dietary spermidine intake was associated with reduced rates of cancer, cardiovascular disease, and improved overall survival. ¹⁸

Curcumin and quercetin address two further hallmarks that autophagy alone cannot reach. Curcumin targets chronic low-grade inflammation — the persistent, silent inflammatory state that builds with age and is distinct from the acute inflammation of an injury. It works by suppressing NF-κB, the molecular switch that drives inflammatory gene expression throughout the body. ¹⁹ Quercetin goes a step further: rather than dampening the environment that zombie cells create, it helps clear them directly. Senescent cells resist normal programmed cell death; quercetin inhibits the survival pathways they rely on, nudging them toward apoptosis. It also provides a secondary autophagy-inducing effect via mTOR modulation, reinforcing what spermidine initiates. ²⁰

Three compounds, three distinct pathways: spermidine clears cellular debris through autophagy, curcumin quenches chronic inflammation, quercetin removes the senescent cells that fuel both. All three are delivered in Phytosome™ form — the same phospholipid-bonding technology used across For Youth's range — because both curcumin and quercetin are notoriously poorly absorbed in standard form. ^{21 22}

For Youth's The Cleanse combines 10mg of SuperMide® Spermidine Trihydrochloride, 250mg of Meriva® Curcumin Phytosome™, and 250mg of Quercefit® Quercetin Phytosome™. Together they address the whole-body tier of the hallmarks framework from three angles that a single-ingredient approach cannot replicate.

If spermidine clears out the cell's debris, urolithin A goes one step further: it triggers mitophagy, the selective removal and renewal of damaged mitochondria specifically. ²³ The distinction matters. Not all autophagy targets mitochondria; mitophagy is the quality-control process dedicated to the cellular power plants themselves. As mitochondria accumulate damage over time, they become less efficient and begin generating more reactive oxygen species than useful energy. Mitophagy clears the dysfunctional ones and stimulates the biogenesis of new, healthier replacements. It is, in effect, a renewal programme for the machinery of cellular energy. ²⁴

Urolithin A is a postbiotic, meaning it is produced in the gut from dietary polyphenols found in pomegranate, walnuts, and certain berries. The catch is that its production depends entirely on the composition of your gut microbiome, and studies suggest that roughly 60 percent of people lack the specific bacteria needed to produce meaningful amounts. Supplementation bypasses this variability. ²⁵ A clinical trial published in Nature Aging found that urolithin A supplementation over four months in middle-aged adults increased markers of mitophagy in muscle tissue, improved muscle endurance, and boosted mitochondrial gene expression. ²⁶ A 2025 follow-up study found that it also rejuvenated CD8+ immune cells, shifting them toward a more energetically efficient, youthful profile. These are not trivial results: they connect directly to the hallmarks of mitochondrial dysfunction and stem cell exhaustion. ²⁷

For Youth's The V-Max pairs 500mg of MitoAge™ Urolithin A, a pharmaceutical-grade, purity-verified form, with 150mg of Ubiqsome® CoQ10 Phytosome™. CoQ10 is essential for the mitochondrial electron transport chain and ATP production; its levels also decline with age. ²⁸ Ubiqsome® delivers CoQ10 complexed with sunflower phospholipids for substantially greater absorption than standard CoQ10, making the combination both a mitochondrial renewal agent and a mitochondrial fuel source in a single capsule. ²⁹

Of all the whole-body effects of ageing, cognitive decline is perhaps the one people fear most. It is also one of the most complex: the hallmarks of altered intercellular communication, chronic inflammation, and mitochondrial dysfunction all converge in the ageing brain, compounding the challenge. The emerging science of neuroprotection suggests that the most promising approach is not a single molecule but a layered strategy, one that protects neurons against oxidative damage while also supporting cerebral blood flow, neuroplasticity, and stress resilience. ³⁰

Ergothioneine is an amino acid found in high concentrations in mushrooms that the body cannot synthesise on its own and must obtain through diet or supplementation. Its levels are known to decline with age, and lower blood levels have been associated with cognitive impairment and neurodegeneration in observational studies. Ergothioneine accumulates in tissues that face high oxidative stress, including the brain and liver, via a highly specific cellular transporter. ³¹ Research by Professor Barry Halliwell and Dr Irwin Cheah at the National University of Singapore has identified it as one of the most promising compounds for long-term neuroprotection, showing that it reduces oxidative stress in neurons, supports neurogenesis, and may help mitigate telomere shortening in brain cells. ³²

Ginkgo biloba extract, standardised to 24% flavone glycosides and 6% terpene lactones, has one of the longest evidence trails in cognitive research: randomised trials have shown improvements in memory, processing speed, and cerebral blood flow. ³³ Rhodiola rosea, an adaptogen with a well-established profile in stress physiology, reduces cortisol-related neuronal fatigue and improves cognitive performance under sustained mental load. ³⁴ The combination addresses both the structural and functional dimensions of brain ageing.

For Youth's The Brain brings these three together: ErgoX™ Ergothioneine for long-term neuronal protection, Ginkgo biloba 24/6 for circulation and memory, and Rhodiola rosea for stress resilience and mental fatigue. It is designed to deliver near-term clarity while building the kind of structural protection that matters over years and decades, which is ultimately what healthspan in the cognitive domain requires.

Sleep is not simply rest. It is the period during which the brain runs its own glymphatic clearance system, flushing out the metabolic waste products, including amyloid-beta peptides, that accumulate during waking hours. Chronic poor sleep is associated with accelerated epigenetic ageing, elevated inflammatory markers, impaired glucose metabolism, and reduced cognitive resilience. ³⁵ In the language of the hallmarks, sleep disruption touches altered intercellular communication, chronic inflammation, and epigenetic alterations simultaneously. It is one of the most potent and underappreciated modulators of biological ageing.

Magnesium is involved in over 300 enzymatic reactions in the body, including those governing neurotransmitter synthesis, synaptic regulation, and the activation of GABA receptors that promote relaxation and sleep onset. ³⁶ The difficulty has always been getting it to the brain: most magnesium supplements are poorly absorbed and do not cross the blood-brain barrier in meaningful quantities. Magtein® Magnesium L-Threonate is the only form of magnesium demonstrated to do so reliably. A 2026 randomised, double-blind, placebo-controlled trial found that six weeks of Magtein® supplementation reduced estimated cognitive age by 7.5 years on the NIH Total Cognition Composite, with significant improvements in working memory and reaction time. A companion study on adults with sleep disturbance found meaningful improvements in sleep-related impairment and cardiovascular markers including heart-rate variability. ³⁷ 

For Youth's The Unwind combines 1000mg of Magtein® Magnesium L-Threonate with 250mg of L-theanine, the amino acid found in green tea that promotes alpha brain wave activity and calm alertness without sedation. ³⁸ Together they support the transition into restorative sleep and, through the downstream effects of better sleep quality, address several of the hallmarks most sensitive to the circadian cycle. Sleep quality may be the least glamorous target in longevity science. It is also, evidence increasingly suggests, one of the most consequential.

What makes these six supplements worth considering together is precisely the breadth of the hallmarks they collectively address. The Repair targets the epigenetic and metabolic dimensions of cell damage. The Protect shields against oxidative genomic instability. The V-Max renews mitochondrial function from within. The Cleanse activates autophagy, clears senescent cells, and damps chronic inflammation. The Brain protects the neuronal communication networks that degrade with age. The Unwind restores the sleep architecture that underpins the body's nightly repair cycle.

That is all three tiers of the hallmarks framework, addressed through complementary and mutually reinforcing mechanisms.

For Youth bundles The Repair, The Protect, and The Cleanse as The Age Defence System, a once-daily core protocol for cellular health. The V-Max, The Brain, and The Unwind extend that foundation to mitochondrial renewal, cognitive protection, and sleep quality respectively. Together they represent a comprehensive, science-guided approach to the hallmarks of ageing that goes well beyond what any single molecule can accomplish.

All products are formulated by Dr Jan Gruber and Dr Vincenzo Sorrentino, professors at the National University of Singapore, and manufactured to GMP standards with third-party purity testing. The transparency of sourcing and clinical references is, in this field, less common than it should be.

It would be a disservice to science, and to readers, to present the longevity supplement field as a solved problem. It is not. The human trials for most of these compounds, including NMN, are still in relatively early stages.

The biohacker community, a loose network of self-experimenters who have been stacking these compounds for years, tracking blood work, biological age tests, and subjective markers, provides a parallel stream of anecdotal evidence that is genuine but methodologically limited. People report improvements in energy, cognitive clarity, and recovery. Without controls, blinding, or standardised measurement, those reports are suggestive rather than conclusive. They are, however, part of why this space has attracted as much serious scientific attention as it now has.

Every few months, something new appears in the longevity literature that makes researchers sit up. Some of it will eventually change how we think about ageing. Some of it will not survive contact with better-designed trials. The honest challenge is telling the difference early — and the honest answer is that we often can't. Here are four areas that deserve serious attention, along with the questions they have yet to answer.

Fisetin is a flavonoid found in strawberries that belongs to the same senolytic family as quercetin; compounds that selectively clear zombie cells from tissues. ³⁹ The preliminary evidence is striking. A 2025 study at the University of Colorado Boulder found that fisetin reduced frailty and improved grip strength in aged mice to a degree comparable with pharmaceutical-grade senolytics. ⁴⁰ The open questions, though, are real: fisetin requires high doses to produce senolytic effects in animals, and its bioavailability in humans is poor. ⁴¹ Does enough of it actually reach the tissues where zombie cells accumulate? And if effective doses in humans are very high, what does that mean for long-term safety? These are the trials we're waiting for.

Alpha-ketoglutarate (AKG) is a metabolite your cells produce naturally during energy metabolism. It has an unusual property: in mouse studies, supplementing with calcium AKG compressed morbidity more dramatically than it extended lifespan, meaning the animals spent less of their lives in a frail or diseased state. ⁴² That distinction matters. A small human observational study found an average eight-year reduction in biological age after seven months of supplementation. ⁴³But observational studies are notoriously difficult to interpret: were the participants already unusually health-conscious? Did other lifestyle factors confound the result? The ABLE trial, a rigorous randomised controlled trial currently underway, is testing AKG specifically in people whose biological age runs ahead of their chronological age. ⁴⁴ Its results could be genuinely clarifying, or they could raise a new set of questions.

Trimethylglycine (TMG) works differently from most longevity compounds. It doesn't target a hallmark directly; instead, it donates methyl groups, the chemical units needed for DNA methylation, gene regulation, and keeping homocysteine, a cardiovascular risk factor, in check. ⁴⁵ The longevity connection is partly downstream: as NMN raises NAD+ and activates sirtuin enzymes, those enzymes consume methyl groups, potentially depleting the body's methylation reserves. TMG replenishes them. Some researchers take it routinely alongside NMN for this reason. The question is whether the methylation depletion effect is large enough in practice to matter, and whether TMG supplementation produces a measurable benefit on top of an already-optimised NAD+ protocol. The human data are thin. The biological logic is sound. This is a compound that may need a decade of better-designed studies before we really know what it does.

Sirolimus sits at the pharmaceutical end of the longevity spectrum, which makes it a different kind of conversation. Originally developed as an immunosuppressant for transplant patients, it inhibits mTOR, a pathway that governs cell growth and metabolism and, when chronically overactive, accelerates many of the hallmarks of ageing. ⁴⁶ In animal studies, sirolimus is the most robustly replicated longevity intervention ever tested. ⁴⁷ The 2024 PEARL trial enrolled 114 healthy adults on weekly low-dose sirolimus and found improvements in muscle mass, pain, and quality of life. ⁴⁸ A 2025 GeroScience pilot found meaningful improvements in cardiac and vascular function after eight weeks. ⁴⁹ And yet a rigorous 2025 review found no trial has directly demonstrated that sirolimus slows biological ageing in humans. ⁴⁷ The central unanswered question is a serious one: mTOR regulates not just ageing but immune function, wound healing, and metabolic balance. 

What unites these four compounds is not uncertainty about whether they matter, but uncertainty about the specifics: dose, timing, who benefits most, and what the long-term trade-offs look like. Biological age testing is becoming the most useful tool for beginning to answer those questions, allowing researchers and individuals to track whether an intervention is producing real change at the cellular level, rather than relying on molecular proxies that may or may not translate to lived health. ⁵⁰

The science of longevity supplementation is, in the fullest sense, a science in progress. It is not yet the kind of settled, consensus-backed field that lets a journalist write with the confident authority that accompanies, say, the evidence for statins or vaccines. But the direction of travel is clear, the mechanistic logic is sound, and the compounds at the frontier of this research, NMN, sulforaphane, glutathione, spermidine, curcumin, quercetin, have better evidence behind them than the vast majority of what fills supplement shelves.

More importantly, the underlying framework is changing what it means to think about health. The hallmarks of ageing give us a vocabulary and a set of targets. Healthspan gives us a more honest goal than lifespan ever was. And the growing body of research suggests that with the right compounds, taken consistently, alongside exercise, sleep, and a sound diet, there are real biological levers available to people who want to age not just longer, but genuinely better.

That is a more modest claim than the supplement industry often makes. It is also, given where the science now stands, a more honest and more interesting one.