Energy & Longevity
Taurine and Aging: The 2025 Follow-Up Found Levels Rise, Not Fall
Key takeaways
- The 2023 Science paper's core observation was a decline in circulating taurine with age. That is the claim the 2025 follow-up could not reproduce.
- Fernandez et al., Science 2025: taurine increased or remained unchanged with age in three human cohorts, in nonhuman primates and in mice, measured longitudinally and cross-sectionally.
- Marcangeli et al., Aging Cell 2025: 137 men aged 20 to 93, no significant correlation between taurine and age, muscle mass, strength, performance or mitochondrial function.
- The 2023 paper's own closing line asked for clinical trials in humans. It was a hypothesis paper, sold as a conclusion.
- This is not a claim that taurine is harmful. It is a claim that the specific reason you were given to buy it did not survive.
- There is no product box on this page, and that is the point of the page.
Most supplement stories end with a trial that did not work. This one ends earlier than that, and the earlier ending is more interesting.
The claim that built the category
June 2023, Science, a paper titled “Taurine deficiency as a driver of aging.” Its central observation, in the authors’ own words:
We find that concentrations of circulating taurine decline with aging in mice, monkeys, and humans.
Then the intervention: reversing that decline through supplementation increased health span in mice and monkeys, and life span in mice. Plus a stack of mechanisms — reduced cellular senescence, protection against telomerase deficiency, suppressed mitochondrial dysfunction, less DNA damage, attenuated inflammaging.
It is a genuinely impressive piece of work, and the coverage it received was proportionate. Within months taurine had moved from a word on an energy drink can to a longevity supplement with a rationale.
The rationale is a single chain: it falls as you age → put it back → you age more slowly.
The check
June 2025, the same journal, a paper from a National Institute on Aging team led by Fernandez, with Ferrucci and de Cabo among the authors. Title: “Is taurine an aging biomarker?”
They went looking for the decline in more places, and with better study designs. Verbatim:
We found that circulating taurine concentrations increased or remained unchanged with age in three geographically distinct human cohorts as well as in nonhuman primates and mice when measured longitudinally (repeatedly in the same population) or cross-sectionally (sampling distinct populations at various ages).
Read that once more. Not “the decline was smaller than reported.” Not “we could not detect a change.”
Increased.
Three human cohorts in different parts of the world, plus monkeys, plus mice. And critically, longitudinally — the same people measured repeatedly as they aged, which is the design that answers this question properly. A cross-sectional snapshot compares a 30-year-old to a 70-year-old and hopes the two groups differ in nothing but age. Following one person from 30 to 70 does not need that hope.
Their conclusion:
Our results suggest that changes in circulating taurine are not a universal feature of aging and that its pleiotropic effects may be dependent on the temporal and physiological context of each individual.
Why this is a bigger problem than a failed trial
We write a lot of articles here that end with “the trial found no significant difference.” Those articles say: the intervention did not produce the outcome.
This one says something structurally worse for the product. The deficiency being corrected may not be there.
| The chain | Status |
|---|---|
| Taurine falls with age | Not reproduced. Increased or unchanged across three human cohorts, primates and mice |
| Restoring it extends health span in animals | Stands, on the 2023 paper’s own experiments |
| The same applies to humans | Never tested in a trial; the 2023 authors said so themselves |
If the first row does not hold, the third row has nothing to stand on, regardless of how good the second row is.
The human test
A separate 2025 paper went at the human question directly. Marcangeli, Cefis and colleagues, in Aging Cell, evaluated 137 men aged 20 to 93, both physically inactive and active. They measured circulating taurine and looked for associations with age, muscle mass, strength, physical performance and mitochondrial function.
No significant correlations. The paper is titled “Experimental Evidence Against Taurine Deficiency as a Driver of Aging in Humans.”
Note what was measured there: not a vague wellness score, but muscle mass, strength and mitochondrial function — the exact outcomes taurine is marketed on.
The sentence in the 2023 paper nobody put on a label
The original paper’s final line:
Clinical trials in humans seem warranted to test whether taurine deficiency might drive aging in humans.
That is researchers doing their job properly. They stated the limit of what they had shown and asked for the study that would settle it. And the sentence before it lists exactly which species the conclusion covers: health span in worms, rodents and primates, life span in worms and rodents.
Between the publication of that request and any answer to it, a consumer product appeared, built on the request as though it were the answer.
What this page does not say
- It does not say taurine is dangerous. Nothing here is a safety finding.
- It does not say the 2023 paper was bad science. It was a serious study, and the disagreement is now being resolved in the open, in the same journal, which is what is supposed to happen.
- It does not say taurine does nothing. Taurine is a normal amino acid, abundant in fish, shellfish and meat, with roles that have nothing to do with this argument.
- It does not say supplementing has been tested and failed. The 2025 Science paper measured whether taurine changes with age; it did not run a supplementation trial. Nothing in it rules out taurine helping some people for some reason. It removes the reason that was actually being advertised.
What it says is narrow and firm: the specific reason you were given to buy it — that it drains away as you age — is the part that failed to replicate.
No product box, on purpose
There is no buy button on this page.
We do place them elsewhere, when an article concludes that something specific and purchasable follows from the evidence — a dose and a form that a trial actually used. That is what makes a recommendation mean something.
Here the conclusion is that a premise came apart. A button under that would be a button under nothing, and once a site has done that a few times, none of its buttons are worth clicking.
The habit worth taking from this
When a supplement is sold on a molecule that “declines with age,” there are three separate claims stacked on each other, and the packaging blurs them into one:
- The observation — the molecule really does decline
- The animal result — restoring it helps a mouse
- The human outcome — restoring it helps you
Most sceptical attention goes to the gap between 2 and 3, because that is where supplement claims usually break. Taurine broke at 1, which is the earliest and least expected place for it to go.
Worth asking, next time: which of the three am I actually buying?
Frequently asked questions
Does taurine decline with age?
That was the 2023 finding and it is the part that did not replicate. The 2023 Science paper reported that concentrations of circulating taurine decline with aging in mice, monkeys, and humans. In 2025 a National Institute on Aging team published the check in the same journal and found the opposite direction: circulating taurine concentrations increased or remained unchanged with age in three geographically distinct human cohorts as well as in nonhuman primates and mice, when measured longitudinally, meaning repeatedly in the same population, or cross-sectionally, meaning sampling distinct populations at various ages. Their conclusion is that changes in circulating taurine are not a universal feature of aging.
Why does the direction of the change matter so much?
Because the entire argument for supplementing rests on it. The logic sold to consumers is: this molecule falls as you age, therefore topping it up restores something youthful. If the molecule does not fall, there is nothing to top up, and the argument has no starting point left. Notice that this is a stronger objection than a failed trial. A failed trial says the intervention did not work. This says the deficiency being corrected may not exist.
Was the 2023 paper wrong, or fraudulent?
Neither word fits, and it is worth being precise. It was a large, serious piece of work published in a top journal, and its animal results, including extended life span in mice, stand on their own experiments. What the 2025 paper challenges is the generalisability of one observation, the age-related decline, when measured in other cohorts and with longitudinal data. The 2025 authors put it carefully: their results suggest that changes in circulating taurine are not a universal feature of aging and that its pleiotropic effects may be dependent on the temporal and physiological context of each individual. That is a scientific disagreement resolving in public, which is the system working rather than failing.
What did the human study find?
Marcangeli, Cefis and colleagues, publishing in Aging Cell in 2025, evaluated 137 men aged 20 to 93, both physically inactive and active, measured circulating taurine, and tested its association with age, muscle mass, strength, physical performance and mitochondrial function. They found no significant correlations, and titled the paper Experimental Evidence Against Taurine Deficiency as a Driver of Aging in Humans. This matters because it is a direct human test of the specific mechanism, rather than an extrapolation from mice.
Did the original authors claim it was proven in humans?
No, and this is the sentence that should have shaped the marketing. Their paper ends: clinical trials in humans seem warranted to test whether taurine deficiency might drive aging in humans. They also framed the conclusion conditionally, that taurine deficiency may be a driver of aging because its reversal increases health span in worms, rodents and primates and life span in worms and rodents. Worms, rodents and primates. The human part was the open question they were asking for permission to study, and it was sold as the answer.
Should I stop taking taurine?
That is a smaller question than it looks. Nothing here says taurine is dangerous, and taurine is a normal dietary amino acid found in fish, shellfish and meat. What has changed is the reason. If you started taking it because you read that it declines with age and topping it up slows aging, the evidence for that specific premise is now contested in the same journal that published it, and a direct human study found no association with age, strength or mitochondrial function. If you take it for a different documented reason, that reason is unaffected by this page.
Does this apply to other anti-aging supplements?
The pattern does. A molecule is observed to change with age, an animal study shows supplementation helps, and a product exists before anyone has run the human trial. The useful habit is to ask which step you are actually buying: the observation, the animal result, or a human outcome. Here, the observation itself is what came apart, which is the earliest and most fundamental place for a chain like that to break.
Why is there no product recommendation on this page?
Because the conclusion does not support one. We place product links when an article concludes something specific and purchasable follows from it, such as a dose and form a trial actually used. This article concludes that a premise failed to replicate. Putting a buy button underneath that would tell you the button means nothing, which would also devalue the ones on pages where the evidence does support a recommendation.
Sources
Every claim above is drawn from these primary sources. Last checked July 2026.
- 1.Fernandez ME, Bernier M, Price NL, Camandola S, Aon MA, Vaughan K, Mattison JA, Preston JD, Jones DP, Tanaka T, Tian Q, González-Freire M, Ferrucci L, de Cabo R. Is taurine an aging biomarker? Science. 2025;388(6751):eadl2116. PMID 40472098. Abstract verbatim: Low circulating taurine concentrations have been proposed as a driver of the aging process. We found that circulating taurine concentrations increased or remained unchanged with age in three geographically distinct human cohorts as well as in nonhuman primates and mice when measured longitudinally (repeatedly in the same population) or cross-sectionally (sampling distinct populations at various ages). Moreover, considerable variability was observed in associations between taurine and age-related changes in health outcomes pertaining to gross motor function and energy homeostasis. Our results suggest that changes in circulating taurine are not a universal feature of aging and that its pleiotropic effects may be dependent on the temporal and physiological context of each individual. Checked 12 August 2026
- 2.Singh P, Gollapalli K, Mangiola S, et al. Taurine deficiency as a driver of aging. Science. 2023;380(6649):eabn9257. PMID 37289866. Abstract verbatim: Aging is associated with changes in circulating levels of various molecules, some of which remain undefined. We find that concentrations of circulating taurine decline with aging in mice, monkeys, and humans. A reversal of this decline through taurine supplementation increased the health span (the period of healthy living) and life span in mice and health span in monkeys. Mechanistically, taurine reduced cellular senescence, protected against telomerase deficiency, suppressed mitochondrial dysfunction, decreased DNA damage, and attenuated inflammaging. In humans, lower taurine concentrations correlated with several age-related diseases and taurine concentrations increased after acute endurance exercise. Thus, taurine deficiency may be a driver of aging because its reversal increases health span in worms, rodents, and primates and life span in worms and rodents. Clinical trials in humans seem warranted to test whether taurine deficiency might drive aging in humans. Checked 12 August 2026
- 3.Marcangeli V, Cefis M, et al. Experimental Evidence Against Taurine Deficiency as a Driver of Aging in Humans. Aging Cell. 2025;24(10):e70191. PMID 41061678. Taurine deficiency was recently proposed as a driver of aging in various species, including humans. This study evaluated 137 men aged 20-93, both physically inactive and active, measuring circulating taurine levels and assessing associations with age, muscle mass, strength, physical performance and mitochondrial function. No significant correlations were found, challenging the implication of taurine deficiency as a primary driver of aging in humans. Checked 12 August 2026