Ask Mary

A woman’s basal metabolic rate rises by 5 to 10 percent during the week before the onset of menstruation.  That would amount to burning 75 to 150 extra calories a day for a woman whose metabolic output measured 1500 calories.  The metabolic rate returns to normal, or slightly less than normal, on the first or second day of menstruation.  Every woman has a cyclical metabolic rate but the timing of the rise and fall is not identical for every women.