Diabetes

Study: 7 Hours, 18 Minutes of Sleep Cuts Diabetes Risk

Does sleeping exactly 7 hours and18 minutes prevent diabetes or is the "sweet spot" just a statistical artifact from flawed data?

Published MAR 5

Study: 7 Hours, 18 Minutes of Sleep Cuts Diabetes Risk

Story

Above: Ander Hersh demos WISP sleep research at the BEL lab in Eugene, Oregon, on May 19, 2022. Image credit: Leah Nash/Washington Post/Getty Images

The Facts

A study published on Wednesday in BMJ Open Diabetes Research & Care analyzed data from 23,475 participants aged 20 to 80 in the National Health and Nutrition Examination Survey between 2009 and 2023, finding that 7 hours and 18 minutes of sleep per night may reduce the risk of insulin resistance.
Good Morning Britain on X
BMJ
GB News
The research used estimated glucose disposal rate — calculated from waist circumference, fasting blood glucose and blood pressure — as a measure of insulin resistance. Lower eGDR values indicate a greater risk of insulin resistance, while higher values suggest reduced susceptibility.
BMJ
Healthline
Participants in the study slept an average of 7 hours and 30 minutes on weekdays, with just over 48% reporting catch-up sleep on the weekend. Those with weekend sleep data slept for an average of 8 hours during weekends.
Medicalxpress
Female First
For individuals sleeping less than the optimal threshold during the week, 1 to 2 hours of weekend catch-up sleep was associated with higher eGDR. However, for those sleeping more than the optimal amount, over 2 hours of weekend catch-up sleep was linked to lower eGDR.
LIGA
The Times (UK)
The study found that sleeping beyond 7 hours and 18 minutes was associated with lower eGDR scores, particularly among women and those aged 40 to 59. Below this threshold, getting more nightly sleep was associated with higher eGDR.
Science 2.0
GB News
Researchers noted a bidirectional relationship between sleep and metabolism, in which poor blood sugar control can lead to abnormal sleep durations and disorders, creating a cycle in which metabolic disruption affects sleep patterns and abnormal sleep further worsens metabolic health.
Healthline
Surrey Live

Sources Split

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CENTER

RIGHT

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The Spin

Narrative A

Sleeping exactly 7 hours and 18 minutes nightly may be the metabolic "sweet spot," helping reduce insulin resistance, the precursor to type 2 diabetes. This corresponds to the highest average eGDR, indicating optimal insulin sensitivity. Weekday sleep below this can be partly offset by 1–2 hours of weekend catch-up, but sleeping beyond the sweet spot or oversleeping on weekends worsens glucose regulation, highlighting the importance of consistently hitting 7 hours 18 minutes each night.

Healthline

Narrative B

The claim that 7 hours 18 minutes is a precise "sweet spot" overstates the evidence. The study relied on self-reported sleep and cannot prove causation. While moderate sleep — roughly 3.5 to 7.5 hours per night — has been associated with lower diabetes risk, there is no exact optimum, and sleeping beyond this range didn’t clearly worsen insulin sensitivity, meaning the strict 7h18m target should not be taken as a definitive prescription for preventing diabetes.