In patients with breast cancer, a short overnight fast of less than 13 hours was associated with a 36 percent higher risk of breast cancer recurrence, according to research published online in the Journal of the American Medical Association Oncology.
Ideal, then, would be eating dinner no later than 7 p.m. and breakfast no earlier than 8 p.m. Not the standard American model, is it? This is the second study done on night-time fasting by researchers at the University of California, San Diego School of Medicine.
Fasting fewer hours per night was associated with significantly less sleep and higher levels of glycated hemoglobin (HbA1c), which is a measure of average blood sugar levels over a period of months. Ellevated HbA1c and poor sleeping habits have been linked to an increased risk of breast cancer. These findings corroborate a paper published in April 2015, in which researchers demonstrated that shorter overnight fasts were associated with worse blood sugar control.
“Previous research has focused on what to eat for cancer prevention, but when we eat may also matter because it appears to affect metabolic health,” said Catherine Marinac, lead author and doctoral candidate at UC San Diego Moores Cancer Center.
The study included 2,413 non-diabetic breast cancer survivors between the age of 27 and 70 studied between 1995 and 2007, with follow up for breast cancer recurrence and mortality. Participants were 86 percent non-Hispanic white and 55 percent were college educated.
“If future trials confirm that habitual prolonged nightly fasting improves metabolic health, this would be an important discovery in prevention that could reduce the risk of cancers, type 2 diabetes, and cardiovascular disease,” said Ruth Patterson, PhD, senior author and leader of the cancer prevention program at Moores Cancer Center.