Skip to content
PesaFit
PesaFit

What is TDEE and why it's the foundation of any diet

Published on

TDEE is the sum of all calories your body burns in a day. Understanding it is the first step to lose fat, build muscle, or maintain weight intentionally.

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day. It is the foundation of any nutritional strategy: whether you want to lose fat, build muscle, or maintain your weight, you need to know your TDEE.

The 4 components of TDEE

Your daily energy expenditure is made up of four elements. Understanding each one helps you know where you can intervene.

  • BMR (60-75 %): calories you burn at complete rest to keep vital functions running.
  • NEAT (15-30 %): non-exercise activity (walking, fidgeting, posture). The forgotten lever.
  • EAT (5-10 %): programmed physical exercise.
  • TEF (8-12 %): diet-induced thermogenesis (digesting, absorbing food).

How to calculate your BMR

Mifflin-St Jeor (1990) is the most accurate formula for the general population. For men: 10·weight(kg) + 6.25·height(cm) − 5·age + 5. For women: same formula minus 161 instead of +5. If you know your body fat percentage, Katch-McArdle is more accurate because it starts from your lean mass.

The activity factor

To go from BMR to TDEE, we multiply by a factor that estimates your total daily activity (NEAT + EAT + TEF):

LevelFactorDescription
Sedentary1.2Desk job, no exercise
Light1.375Exercise 1-3 days/week
Moderate1.553-5 days/week
Active1.7256-7 days/week
Very active1.9Physical job or double training

Why your real TDEE can differ by 15 %

Formulas are population estimates. Your real TDEE depends on variables the calculation cannot capture: lean-to-fat mass ratio, mitochondrial efficiency, NEAT genetics (some people move much more without realizing it), dieting history, and ambient temperature.

Recommendation: use the formula's TDEE as a starting point. Weigh yourself every morning for 3 weeks eating at those calories. If you lose weight, your real TDEE was lower. If you gain weight, it was higher. Adjust and measure again.

Where TDEE fits into your plan

  1. Calculate your TDEE with the calculator.
  2. Set your goal: cut (−20 %), maintain (0 %) or bulk (+10 %).
  3. Calculate your macros at those target calories.
  4. Measure your weight weekly and adjust every 3-4 weeks.

Without a defined TDEE, counting calories is shooting blind: you don't know whether you are eating in a deficit, at maintenance, or in a surplus. And results arrive by chance.

About this guide

Last reviewed
. We review content at least once a year, and sooner if relevant literature comes out. Update policy.
How it is verified
We prioritize meta-analyses, systematic reviews and official positions (ISSN, ACSM, EFSA, WHO, Cochrane). Full methodology · topic: Nutrición y calorías.
Conflicts of interest
Some product links are affiliate links from Amazon España and earn us a small commission at no extra cost to you. How we fund the project.
Medical disclaimer
Educational content. Does not replace consultation with a healthcare professional. More detail.

Spotted an error in a formula or recommendation? Email us at jesus.narvaez.tames@hotmail.com. Corrections are published as an updated note on the guide.

Recibe las guías nuevas por email

Cada viernes te mandamos las 2 guías nuevas de la semana (martes y jueves) y una calculadora relacionada. Sin spam, baja en un clic.

Comments

Ask questions, share your experience or suggest improvements. You need a GitHub account to comment; threads are hosted on Giscus over GitHub Discussions and are public.