Do Longevity Supplements Work? What the Evidence Can and Cannot Tell You
You are looking at a longevity supplement, and beside it is a headline about telomeres, NAD+, biological age or an epigenetic clock. The study sounds impressive. The ingredient may genuinely be connected to the biology being discussed. The difficult part is working out what the study actually proved.
That matters because working can mean several very different things in longevity science.
Some supplements have human evidence showing changes in particular biological markers or health-related outcomes. That is not the same as proving that longevity supplements as a category extend human lifespan. Whether a supplement is worth considering depends on the exact ingredient, dose, people studied, outcome measured and whether the research actually applies to the finished product in your hand.
That is also how we think about Puraz Telomere Health. We believe targeted healthy-ageing support can be worthwhile without pretending that a capsule has proven it can add a set number of years to your life.
One word is causing most of the confusion
Ask whether longevity supplements work and you can get two answers that sound completely opposite, even when both people are looking at valid research. Usually, they are using the word work to mean different things.
First, an ingredient affects a biological process
This is often where longevity research begins. A compound may interact with NAD metabolism, antioxidant systems, telomerase-related biology or another process involved in how cells function over time.
That can make an ingredient scientifically interesting. It gives researchers a reason to study it further. But a biological mechanism is not yet proof that a person taking a commercial supplement will notice a meaningful outcome.
Lab work, animal research and short human studies can all help explain what may be happening. They do not automatically tell us how much difference the finished supplement will make in everyday life.
Next, a biomarker changes
A biomarker is a measurable sign researchers use to track what is happening in the body. In longevity research, that could include NAD-related metabolites, telomere measurements or DNA methylation ageing clocks.
A biomarker result can be useful evidence because it shows something measurable changed. But it still needs careful interpretation. A change in an epigenetic clock is not automatically the same as better mobility, more energy, fewer health problems or longer life.
This is one of the most important distinctions to keep in mind when you see headlines about biological age. The number may have moved. The next question is what that movement means for the person.
Then, people experience a meaningful outcome
For most of us, this is easier to understand. Researchers may look at physical function, metabolic measures, cognitive performance or another outcome that connects more directly with day-to-day health.
Even then, context matters. Who was studied? How old were they? Did they already have a particular health issue? How long did the study run? Was the effect small or large? Did most people respond in the same way?
A result in a specific group over six months or two years can be valuable without being a universal answer for everyone considering healthy ageing supplements in New Zealand.
Finally, people live longer
This is the biggest version of the word work. Showing that a supplement extends human lifespan requires a very different level of evidence from showing that it changes a pathway or biomarker.
Current human research gives us interesting evidence about particular nutrients, biological processes and ageing-related measurements. It does not justify turning every favourable mechanism, telomere result or epigenetic-clock change into a claim that a longevity supplement has been proven to extend life.
That does not mean future research can never show stronger effects. It simply means we should let each study prove what it actually measured, and no more.
What recent human research actually looks like
Several recent studies are useful because they show both why longevity research is exciting and why the details matter.
DO-HEALTH: a few months on an ageing clock is not a few extra months of life
A 2025 Nature Aging analysis looked at 777 generally healthy adults aged 70 and older from the DO-HEALTH trial. The researchers studied vitamin D, omega-3 and a home exercise programme over three years using several DNA methylation measures of biological ageing.
Omega-3 supplementation was associated with small changes across several of these epigenetic measures. For the affected clocks, the reported effects were equivalent to roughly 2.9 to 3.8 months over the three-year period.
That is an interesting result, but it needs the right translation. The trial did not show that participants lived an extra 2.9 to 3.8 months because they took omega-3. It showed a small difference in particular DNA methylation measures used to estimate aspects of biological ageing.
It also matters that these participants were generally healthy adults aged 70 and older. We should not automatically assume the same effect would appear in younger adults, people with different health profiles or people taking a different supplement.
COSMOS: statistically measurable does not automatically mean clinically meaningful
In March 2026, a Nature Medicine analysis of 958 COSMOS participants reported that a daily multivitamin produced modest changes in two second-generation epigenetic clocks over two years. Cocoa extract did not significantly affect the five clocks assessed.
The researchers described the multivitamin effects as statistically significant but small and said more research is needed to understand their clinical relevance.
This is a useful example of why a measurable result and a meaningful customer outcome are not the same question. A study can detect a real difference in a biomarker while still leaving us unsure how much that difference matters to function, healthspan or lifespan.
NAD+ precursors: strong biochemical interest, mixed broader outcomes
NAD+ is central to cellular metabolism, so it is easy to see why nicotinamide riboside, known as NR, and nicotinamide mononucleotide, known as NMN, have attracted so much attention.
A 2025 Nature Metabolism review concluded that human evidence remains much more limited than the enthusiasm generated by preclinical research. A 2026 systematic review in Ageing Research Reviews found that oral NR and NMN consistently changed NAD-related biochemical measures in humans, while effects on metabolic, vascular, performance and other healthspan-related outcomes were mixed or often absent.
That is a perfect example of the different meanings of work. The compounds can affect the target biology. That does not mean every broader anti-ageing promise has been established.
Astragalus and telomeres: promising, but product-specific
A 2024 randomised, double-blind, placebo-controlled trial followed 40 healthy middle-aged adults for six months. It reported changes in telomere measurements in the group taking a particular Astragalus-based nutritional supplement compared with placebo.
That is worth paying attention to. Human, placebo-controlled telomere research is directly relevant to the questions many people ask about telomere supplements.
It also has clear boundaries. The study was small. It tested one particular finished supplement. It did not test Puraz Telomere Health. It does not show that every Astragalus formula will produce the same result, and it did not demonstrate human lifespan extension.
The formula in your hand may not be the formula in the study
This is where good evidence can be stretched too far without anyone necessarily noticing.
Imagine a study tests a particular Astragalus extract at a particular dose in a particular finished formula. A different product may also say Astragalus on the label, but the extract strength, standardisation, dose and supporting ingredients can all be different.
The delivery format may differ. The people taking it may differ from the study population. The finished product itself may never have been tested for the outcome being discussed.
That does not make ingredient research useless. It tells you what kind of support or biological idea may be worth investigating. It simply means ingredient evidence should not be quietly upgraded into proof for every bottle containing that ingredient.
If you want to compare formulas more carefully, our guide to reading a supplement label in New Zealand shows how to compare full serving sizes, ingredient amounts and front-of-pack claims without getting distracted by one big number.
In New Zealand, careful wording is important for another reason too. The current Therapeutic and Health Advertising Code requires health advertising to be truthful, balanced and supported by appropriate evidence, while Medsafe guidance says dietary supplement labelling and marketing cannot include therapeutic claims.
Why we stop at support, not lifespan promises
We built Telomere Health for people who specifically want targeted telomere, antioxidant and cellular healthy-ageing support. We think that is a useful, realistic reason to consider a longevity-focused supplement.
Our two-capsule serve contains:
- 400 mg bovine collagen hydrolysate peptides
- 200 mg Astragalus Extract standardised to 10 percent Astragaloside IV
- 200 mg reduced L-Glutathione
- 100 mg antioxidant complex
- 85 mg baicalin
- 50 mcg selenium from selenomethionine
The antioxidant complex includes 36 mg ascorbic acid and at least 36 mg fruit-derived phenolic antioxidants. Telomere Health is made in New Zealand and contains no fillers or additives.
We like the formulation because it does not rely on one headline ingredient. The standardised Astragalus extract sits alongside glutathione, baicalin, selenium and antioxidant support in a formula designed around telomere-focused and cellular healthy-ageing support.
We do not turn independent Astragalus research into a clinical claim for our finished product. We also do not ask you to believe Telomere Health has been proven to extend lifespan. You can reasonably choose targeted healthy-ageing support without requiring a supplement to prove that it adds years to your life.
Take two capsules once daily. Do not take during pregnancy or lactation. If you are taking medication, check with a doctor before starting a dietary supplement.
So can a longevity supplement still be worth considering?
Yes, when the job you want it to do is specific and realistic.
If your goal is targeted support for a particular area of healthy ageing, you do not need to demand proof of lifespan extension before a supplement can be useful to you. What you do need is a clear formula, sensible expectations and evidence that is relevant to the ingredients and type of support you are considering.
For a Puraz customer, Telomere Health may suit someone whose interest is specifically telomere-focused, antioxidant and longer-term cellular healthy-ageing support. That is a much more defensible reason to explore it than expecting a bottle to deliver a promised number of extra years.
If your goals are broader, our Healthy Ageing collection brings together different types of support so you can start with what matters most to you rather than chasing every longevity trend at once.
And if you already take several products, it is worth checking for repeated nutrients before adding another. Our guide to avoiding supplement overlap can help you look at your whole daily intake more clearly.
Common questions
Do longevity supplements actually work?
Some longevity supplements and ingredients have human evidence showing changes in specific biological markers or health-related outcomes. That does not prove that longevity supplements as a category extend human lifespan. The most useful question is whether the exact product has evidence relevant to the support you want.
Can supplements extend your lifespan?
Current human studies on popular longevity supplements do not establish that taking them will extend lifespan by a predictable amount. Research may show effects on mechanisms, biomarkers or selected health outcomes, but those results should not be treated as direct proof of longer life.
Can supplements slow biological ageing?
Some trials have reported small changes in biological-ageing biomarkers such as DNA methylation clocks. These findings are scientifically interesting, but a change in a clock does not automatically mean better health, better function or a longer life.
What does it mean when a longevity supplement changes a biomarker?
It means researchers measured a biological sign and found a difference. The next question is whether that change leads to a meaningful outcome for people. Biomarkers can be useful evidence, but they are not automatically the same as clinical benefit or lifespan extension.
Are NMN and NAD supplements proven to slow ageing?
Human studies show that NR and NMN can change NAD-related biochemical measures, but broader results for function, metabolism and healthspan are inconsistent. That means the biology is active, while the larger anti-ageing claims remain less certain.
Do telomere supplements lengthen telomeres?
A small 2024 placebo-controlled trial reported telomere changes with one specific Astragalus-based finished supplement. That result cannot be assumed for every telomere product. For more detail on comparing this category, see our guide to choosing a telomere supplement in New Zealand.
Does ingredient research prove a finished supplement works?
No. Ingredient research can support the scientific rationale for a formula, but the dose, extract standardisation, delivery format, supporting ingredients and study population may differ. Evidence from one ingredient or finished product should not automatically be transferred to another formula.
What should you look for in a longevity supplement in New Zealand?
Look for a clear serving size, transparent ingredient amounts, sensible health-support wording and a formula that matches the specific area you want to support. Be cautious when a biomarker or ingredient study is presented as though it proves a much bigger lifespan claim.
What can Puraz Telomere Health realistically support?
We designed Puraz Telomere Health for targeted telomere, antioxidant and cellular healthy-ageing support. It combines standardised Astragalus Extract with glutathione, baicalin, selenium, an antioxidant complex and collagen hydrolysate peptides. We do not position it as proof of lifespan extension or a predictable change in biological age.
A better way to read longevity claims
The next time you see a headline about a longevity ingredient, ask what the study actually showed. Did a biological process change? Did a biomarker move? Did people experience a meaningful outcome? Or did the research genuinely show longer human life?
Those are not interchangeable results.
A study can be real and interesting without proving everything a broad longevity claim might suggest. In the same way, a supplement can still be worth exploring when it offers targeted support that matches what you actually want.
If telomere-focused and antioxidant support is your priority, we think Telomere Health is a strong option to consider. If you want to explore other healthy-ageing goals as well, you can browse our wider Puraz range below.
References
- Bischoff-Ferrari HA et al. Individual and additive effects of vitamin D, omega-3 and exercise on DNA methylation clocks of biological aging in older adults from the DO-HEALTH trial. Nature Aging. 2025.
- Li S et al. Effects of daily multivitamin-multimineral and cocoa extract supplementation on epigenetic aging clocks in the COSMOS randomized clinical trial. Nature Medicine. 2026.
- Vinten KT et al. NAD+ precursor supplementation in human ageing: clinical evidence and challenges. Nature Metabolism. 2025.
- Gallagher C, Emmanuel OO. NAD+ supplementation for anti-aging and wellness: a PRISMA-guided systematic review of preclinical and clinical evidence. Ageing Research Reviews. 2026.
- de Jaeger C et al. A Natural Astragalus-Based Nutritional Supplement Lengthens Telomeres in a Middle-Aged Population: A Randomized, Double-Blind, Placebo-Controlled Study. Nutrients. 2024.
- Advertising Standards Authority. Therapeutic and Health Advertising Code. Current from 2026.
- Medsafe. Regulation of Dietary Supplements. New Zealand.