Reacción a "Taurine is not a reliable marker of ageing, study shows"

This article is published in the journal Science to disprove earlier findings published in the same journal which seemed to indicate that taurine levels decline during ageing. These data had led to the postulation of the possibility of using blood taurine levels as an indicator of biological ageing, and it had even been proposed that taurine supplementation to restore higher levels could be an anti-ageing intervention.

It is most surprising, and at the same time refreshing and satisfying, to find high-level publications describing ‘negative’ results. The ‘business’ of science is always built on positive results, often disdaining negative results, as if finding that something does not work as expected is not also of great relevance and help in the field.

The group led by Spaniard Rafa de Cabo, one of the world leaders in research into the biological basis of ageing, at the head of his group at the NIH's NIA in the US, has drawn on a wealth of data from longitudinal studies (those in which the same individuals are sampled over time) of ageing in mice, monkeys and humans. The evidence shows that taurine levels vary more between individuals due to different factors than age. In order for a molecule to be considered a true biomarker of ageing, its levels should vary primarily with age and not, as the authors show, by factors specific to each individual that are unrelated to age.

This work demonstrates how important it is to conduct longitudinal studies involving a large number of individuals, across a wide age range and in different species. This is the only way to achieve consistent and robust results. But it also shows how important it is to publish negative results that contradict previous views. Only then can we move in the right direction, amending previous views biased by insufficiently robust results.