Research

Hormonal

Extending the nightly fasting interval to 13 or more hours is associated with a significantly lower risk of breast cancer recurrence in women with early-stage breast cancer compared to fasting less than 13 hours.

If you have had early-stage breast cancer, try to extend the time between your last meal of the day and your first meal the next morning to at least 13 hours. For example, finish dinner by 7 PM and don't eat breakfast until 8 AM. This simple timing strategy is associated with a lower risk of cancer returning, likely because it helps regulate blood sugar and improves sleep.

GoodSupportsHIGH confidence
fasting less than 13 hours per night (lower 2 tertiles of nightly fasting distribution) was associated with an increase in the risk of breast cancer recurrence compared with fasting 13 or more hours per night (hazard ratio, 1.36; 95% CI, 1.05-1.76).
Catherine R. Marinac et al. · JAMA Oncology · 2016

Why this rating

Large prospective cohort (n=2413) with repeated measures and multivariable adjustment, but it is observational and subject to residual confounding.

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×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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