Medically reviewed by Kayla Girgen, RD The average adult woman needs about 1,600-2,400 calories a day.A calorie deficit, in which you take in fewer calories than you burn, is necessary for weight loss ...

Corrections & clarifications: An earlier version of this story misspelled the name of the spokesperson for the Academy of Nutrition and Dietetics. She is Caroline Susie. Few things are as essential as ...