Optimizing your chance of beating breast cancer is now no longer just a matter of what you eat; it’s a matter of when you eat those foods that are good for you.
Scientists at the University of California in San Diego studied 2413 breast cancer survivors between the age of 27 and 70 for twelve years (1995-2007). The question the lead researcher, Catherine Marinac, hoped to answer was, “Does prolonged fasting overnight improve survival for women with breast cancer?” The answer, published in The Journal of the American Medical Association, Oncology in March of this year, was “Yes.”
Women who fasted at least 13 hours between dinner and breakfast had a 36% reduction in their risk of breast cancer recurrence. Why? The answer isn’t yet clear, but there are some hints related to blood sugar levels. We know that elevated blood sugar levels increase the risk for breast and other types of cancer. Elevated blood sugar, especially when it morphs into the chronic disease state of diabetes, increases a woman’s chance of recurrence and death from breast cancer. This is likely related to the growth-stimulating effects that elevated blood sugar levels produce via increased insulin production. Which is to say, anything that increases blood sugar increases the production of insulin, which acts as a stimulant to the growth of tumor cells. Consequently, anything that lowers blood sugar levels, such as a prolonged overnight fast of 13 hours or more, might reduce the risk of breast cancer recurrence by lowering insulin levels for a prolonged interval.
What a simple step: arrange at least 13 hours of fasting between dinner and breakfast. As an example, I usually have breakfast at 7:15 a.m. Therefore, I need to have finished my dinner by 6 p.m. Well, I have to admit, that’s not so simple as it might seem. I mean, what if I don’t get home until 7:30 p.m. and haven’t yet had dinner, but need to get up at 6:00 a.m. the next day? I think the point is to try for an overnight fast of 13 hours. As often as you can, get your dinner in early in the evening and try, as often as possible, to delay breakfast until 13 hours later. I’m certainly going to give it a try. It won’t work perfectly. Nothing ever does. But, it’s worth a try, and it sure looks like it’s the smart thing to do whether you have breast cancer and want to prevent its recurrence, or you don’t have breast cancer and you want to lower your overnight insulin levels just to play it safe.
Reference: C Marinac, “Prolonged nightly fasting and breast cancer prognosis”, JAMA Oncology, 2016.