Sleeping more than 9 hours a night doesn’t make your heart healthier—once you’re getting 7 to 8 hours, sleeping longer won’t lower your risk of heart disease.

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Pro

39

Against

Evidence from Studies

Supporting (0)

0

Community contributions welcome

No supporting evidence found

Contradicting (1)

39

Community contributions welcome

39

Causal association between sleep duration, daytime napping, sleep disorders and ischemic heart disease: A systematic review and meta‑analysis of Mendelian randomization studies

Systematic Review With Meta-Analysis

Human

2025 Dec

The study found that sleeping more than 8 hours actually lowers the risk of heart disease, but the claim says it doesn’t help — so the study says the claim is wrong.

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Source Study

Causal association between sleep duration, daytime napping, sleep disorders and ischemic heart disease: A systematic review and meta‑analysis of Mendelian randomization studies

Score: 39

DOI: 10.1016/j.ijcha.2025.101811

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