Does ergothioneine work as a longevity supplement?

Ergothioneine is a compound found naturally in mushrooms that the body actively absorbs and stores via a dedicated transporter, particularly in tissues vulnerable to oxidative damage, such as the brain. That selective storage mechanism is well documented and is biologically plausible as an explanation for why the compound could be of interest in the context of ageing.

In animal research, life-span extension and improvements in overall health at older ages have been reported, including through better mitochondrial function and inhibition of cellular senescence. That sounds promising, but the effect has not yet been demonstrated in humans.

The only direct clinical experiment in humans is a small pilot study involving 19 older adults with mild memory complaints. They took a supplement for one and a half years and subsequently showed better learning performance, while a blood marker for neuronal damage remained stable. In the placebo group, both measures worsened. That is a positive signal, but with 19 participants no firm conclusions can be drawn.

Safety does not appear to be a major concern. Blood, kidney and liver values remained unchanged over a year of supplement use in older adults. That is reassuring, although here too the evidence is limited to that one small study.

Ergothioneine can be obtained through ordinary food, with mushrooms as the primary source. Modern agricultural practices substantially reduce its levels in other crops. Whether and how much a person typically obtains through diet is poorly studied. The claim that ergothioneine is an indispensable 'longevity vitamin' is a hypothesis that still awaits large, well-designed studies.