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