Research

Hormonal

Extending nightly fasting duration is associated with improved glucoregulation (lower HbA1c) and longer sleep duration, which are proposed mechanisms for the reduced breast cancer recurrence risk.

A longer nightly fast helps your body regulate blood sugar better and may help you sleep longer. These improvements in metabolic health and sleep are likely why extending your fast might help prevent breast cancer from coming back.

GoodSupportsHIGH confidence
each 2-hour increase in the nightly fasting duration was associated with significantly lower hemoglobin A1c levels... and a longer duration of nighttime sleep.
Catherine R. Marinac et al. · JAMA Oncology · 2016

Why this rating

Strong observational data with repeated measures, but causality of the mechanism is inferred, not proven by intervention.

Source

Prolonged Nightly Fasting and Breast Cancer Prognosis

Catherine R. Marinac et al. · JAMA Oncology · 2016

DOI 10.1001/jamaoncol.2016.0164

cohort · n=2413Cited 179×
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DOI resolved against Crossref · corpus check 2026-06-10

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