Background
Postmenopausal breast cancer risk increases twofold in women who gain significant amounts of weight [1] and there is evidence that energy restriction may reduce risk [2]. Animal studies indicate that intermittent energy restriction (IER) reduces risk and may be superior to continuous energy restriction (CER) [3]. We have shown that CER reduces breast cancer risk biomarkers in women but is hard to maintain. We hypothesise that IER may be superior to CER in reducing biomarkers of breast cancer risk and may also be more acceptable to women.