TDEETotal Daily Energy Expenditure

TDEE (Total Daily Energy Expenditure) is the total number of calories your body uses in a day. It is the sum of your basal metabolic rate, the energy cost of digesting food, deliberate exercise, and all your other daily movement (NEAT).

It matters because it is the anchor for any nutrition goal: eating below your TDEE drives fat loss, above it supports muscle gain and weight gain, and around it maintains weight.

In practice, TDEE is estimated by calculating BMR and multiplying by an activity factor, then adjusted based on real-world weight change over a few weeks.