Just lose it!

Here's how to calculate TDEE and calorie deficit to lose fat, writes Rahul Gopal

The last time we looked at the components of Total Daily Energy Expenditure (TDEE), a measure of how many calories you burn per day. This time we will look at how to calculate TDEE and how to calculate a calorie deficit to lose fat. Using the Mifflin St Jeor Equation (it is essential to understand that the final calorie number you calculate is only an estimation. The equations are derived from group averages, the activity multiplier used will be an estimation, and there are individual differences in how people respond to a calorie deficit. Therefore, consider your calculation as a starting point from which to adjust based on how you progress.

Calculate your BMR using the following equations
Men
10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5
Women
10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161

Multiply the calculated BMR with one of the following
(Be conservative here as you can end up eating too much using the wrong multiplier):
1.15: If you are sedentary (little or no exercise) = BMR x 1.15
1.35: If you are lightly active (light exercise/sports 1-3 days/week) = BMR x 1.35
1.55: If you are moderately active (moderate exercise/sports 3-5 days/week) = BMR x 1.55
1.75: If you are very active (hard exercise/sports 6-7 days a week) = BMR x 1.75
1.9: If you are extra active (very hard exercise/sports & physical job or 2x training) = BMR x 1.9

Use the following daily step count guide to gauge activity levels :
Sedentary: Less than 7k steps
Lightly Active: 7-10k steps
Moderately active: 10-14k steps
Very Active: 14-20k steps
Extra Active: >20k steps

A desirable and sustainable rate of loss is between 0.5-1% of your bodyweight, per week, the lower end if you’re relatively lean, the higher end if you have
more fat to lose.

It requires an approximate 3,500 kcal deficit to burn 1 lb of fat (7,700 kcal per kg). Therefore, to lose 1 lb of fat per week, you need a 500 kcal daily deficit (1100 kcal for 1 kg).

The calculation to adjust the calorie intake for a fat loss goal is as follows:
TDEE – (Bodyweight (in kg) x target weekly fat loss rate x 1100)
Let’s understand this with an example: A is a 35-year old woman, who is 165 cm tall, weighs 83kg, and is lightly active (7-10k steps daily). Her goal is to lose the extra fat that she is carrying. Using the Mifflin St Jeor equation, we arrive at 1525 kcal as her BMR. Multiplying that by 1.35, we get 2059 kcal as her TDEE.
Assuming a rate of loss of 0.5% bodyweight per week, she will require
(2059 – (83*0.005 *1100) = 1602 kcal/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.)