Is Sleep Regularity good for longevity?

The evidence points that way, though it's not yet conclusive. Sleep regularity has emerged as an active and increasingly well-supported area of research, with recent large cohort studies (UK Biobank, MESA) finding that day-to-day consistency of sleep timing predicts cardiovascular disease and mortality risk, in some analyses more strongly than sleep duration itself. That's reflected in an evidence score of 66/100 for its role in longevity, drawn from 7 studies, with an estimated impact on longevity rated moderate (59/100).