India, July 29 -- For years, sleep experts have cautioned against getting too much sleep, linking it to heart disease, depression, and even premature death. However, new findings from the largest study of its kind suggest the real issue may not be the amount of sleep but how inaccurately we report it. (Also read: Cardiologist explains how a simple blood test can predict heart attack risk years in advance: 'Before symptoms appear.' )

Researchers equipped nearly 90,000 adults with fitness trackers to objectively measure sleep patterns and followed their health outcomes over seven years. The study published in the journal Health Data Science on June 3, 2025, found that many participants who claimed to sleep more than eight hours were actual...