Peter Lidsky called the damage accumulation model untestable and useless for developing therapies for aging

Peter Lidsky called the damage accumulation model untestable and useless for developing therapies for aging

On August 2, aging biologist Peter Lidsky published an analysis on X of the damage accumulation model. He asks whether the theory can guide an experiment before researchers already have an effective therapy.

The damage accumulation model attributes aging to changes in DNA, proteins, cells, and tissues. Its proponents propose identifying these changes and repairing or removing them to extend healthy life.

“The damage accumulation model is untestable and unproductive,” Lidsky writes.

He examines a standard claim of this model: repairing all damage should stop aging. According to Lidsky, this claim tests the theory only after a therapy has succeeded. A laboratory must first stop aging and can only then determine whether its explanation was correct. This approach does not help researchers choose the next experiment.

Lidsky proposes a different criterion. A theory should specify in advance how an intervention relates to an observation that would lead the researcher to revise the explanation. Otherwise, any age-related change can be labeled as “damage,” and the model cannot distinguish causes from consequences.

Lidsky has previously connected this issue to the behavior of social insects. In a paper published in March, he and his coauthors modeled cases in which adverse conditions trigger longer life or rejuvenation. Their model shows that classical evolutionary explanations of this behavior require additional assumptions. Lidsky now asks what observation the damage accumulation model predicts for such an animal.

The debate grew out of two posts by Alan Cohen about testability in science and the daily work of scientists. Cohen argues that testability depends on the instruments available. Lidsky asks aging theories to meet a more practical standard: they should specify in advance an experiment and a result that would require the theory to be revised.