Is Volunteering good for longevity?

The evidence points that way, though it's not yet conclusive. Formal volunteering has a substantial observational literature linking it to lower mortality, though the size of the effect shrinks sharply once confounders are addressed. That's reflected in an evidence score of 60/100 for its role in longevity, drawn from 6 studies, with an estimated impact on longevity rated moderate (45/100).