Time-Restricted Eating in Menopause and HOrmone-sensitive Breast Cancers (TREMHO)

Inclusion Criteria: * Women with confirmed physiological menopause without current anti-cancer treatment (group A), or women with menopausal symptoms in the context of aromatase inhibitors used as adjuvant therapy for hormone-sensitive non-metastatic breast cancers regardless of physiological menopause before the cancer diagnosis (group B) * Age 40-65 years * Body mass index 25-40 kg/m2 * Stable weight (± 2 kg) over the previous month * Eating window ≥ 12 hours (self-reported and measured during the run-in phase) * Able to give informed consent and follow the study procedures for the entire duration * Confident use of a smartphone and able to take regular pictures of food/drinks Exclusion Criteria: * On a hypocaloric restrictive diet, intermittent fasting or in a weight management program over the previous month * Previous bariatric surgery or planned during the study * Active eating disorder(s) or major mental illness at inclusion * Psychoactive treatment with recent or planned changes of drug compound or dosage * Treatments affecting body weight (e.g. glucocorticoids, GLP-1 receptor analogues) * Diabetes with hypoglycemic drug(s) will be excluded, however those with prediabetes (as defined by the American Diabetes Association) or diabetes with no risk of hypoglycemia (i.e. treated with non-hypoglycemic drugs or without medication) will be included * Active metabolic bone diseases (e.g. Paget disease, osteomalacia), however women with osteoporosis will be included * Shift work comprising night shifts (working between 11pm and 6am) over the previous 2 weeks or planned during the study * Travel/trip to a different time zone (≥ 2-hour time difference) over the previous 2 weeks or planned during the study * Enrolled in another interventional clinical trial (medication, surgery, medical device) over the previous 2 weeks or planned during the study