Does Waiting for the Marshmallow at 4 Predict Success at 30? A 26-Year Follow-Up of 702 Children

A 26-year follow-up of 702 children finds that delay of gratification at 54 months, once family background is controlled, predicted almost nothing about adult outcomes — except BMI. The famous Marshmallow Test’s predictive power collapses under larger samples and proper controls.

May 16, 2026 · 6 min