Reducing the risk of breast cancer recurrence may be supported by prolonging the length of the nightly fasting interval, as improvements in glucoregulation and sleep may serve as mechanisms linking nightly fasting with breast cancer prognosis. This according to a cohort study of 2,413 women (mean age 52.4 years) who reported a mean fasting duration of 12.5 (1.7) hours per night. Researchers found:
• Fasting <13 hours per night was associated with an increase in the risk of breast cancer recurrence compared with fasting ≥13 hours per night (HR, 1.36).
• Nightly fasting <13 hours was not associated with a statistically significant higher risk of breast cancer mortality (HR, 1.21) or a statistically significant higher risk of all-cause mortality (HR, 1.22).
• Each 2-hour increase in the nightly fasting duration was associated with significantly lower hemoglobin A1c levels and a longer duration of nighttime sleep.
Citation: Marinac CR, Nelson SH, Breen CI, et al. Prolonged nightly fasting and breast cancer prognosis. [Published online ahead of print March 31, 2016]. JAMA Oncol. doi:10.1001/jamaoncol.2016.0164.