The last time, we looked at what Calories, Macronutrients and Energy Balance meant. This time we will see what makes up TDEE or Total Daily Energy Expenditure.
Put simply, TDEE is the number of calories you burn each day, which varies. It depends on how much you move, eat, and how many calories you burn at rest. Knowing your TDEE is important — it dictates the number of calories you should be eating to either drop fat (hypocaloric state, eating in a calorie deficit), build muscle (hypercaloric state, eating in a calorie surplus) or be weight stable (eucaloric state, eating at maintenance level). Let’s look into the various components that make up and affect your TDEE:
BMR: Basal metabolic rate: The number of calories you burn at rest. BMR is the number of calories you burn to maintain basic bodily functions; those which keep you alive. BMR accounts for most of your TDEE, comprising 50-75% of your daily energy expenditure. BMR varies between people; by ~250 calories per day on average. As such, your friend’s TDEE may be way different than yours.
TEF: The thermic effect of food: TEF or DIT (Diet-Induced Thermogenesis) is the number of calories you burn to digest and absorb food. Based on averages, TEF is assumed to be constant at ~10% of your TDEE. This is reasonable since TEF generally accounts for ~8-20% of the calories you eat. So, if you eat 2,000 calories per day, you might burn ~260 of those calories during digestion. Assuming you burn 2,100 calories per day, that would be ~12% of your TDEE. However, TEF is higher for mixed meals comprising predominantly whole food sources and higher for lean people (as high as 25%). Typically, TEF is the least variable component of TDEE.
AEE: Activity energy expenditure: AEE, is the number of calories you burn during exercise and casual movement. Activity energy expenditure varies greatly between people and accounts for anywhere between ~5 and 40% of TDEE. Some burn just 1,500 calories per day, whereas others burn over 3,500. Also, some people burn more calories through exercise, yet will burn fewer calories per day. AEE can be further categorised into EAT and NEAT.
EAT: Exercise Activity Thermogenesis: EAT, includes all calories burned during deliberate exercise. Every training session burns calories, and so all exercise increases your EAT. In regular exercisers (e.g. endurance athletes), EAT can account for as much as 15-30% of TDEE. However, EAT doesn’t typically increase daily calorie expenditure by much. In general, it accounts for just ~5% of TDEE, as most people don’t exercise regularly.
NEAT: Non-exercise Activity Thermogenesis: NEAT is the most variable component of TDEE and accounts for calories burned during spontaneous and unplanned movement. This can include walking your dog or typing on your computer. NEAT is higher in those who move around more throughout the day.
(The author is a Chennai-based Sports Nutritionist, Strength and Conditioning Coach and Mobility Specialist. He is also a professional drummer and has a love of all things cats and martial arts.)