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The basic calorie in/calorie out Formula

The basic calorie in calorie out Formula

The basic calorie in/calorie out formula is relatively simple. You need to adjust the calorie expenditure for metabolic rates, activity levels, effectiveness of one’s endocrine system, etc. The basic formula is:

Energy stored = energy in – energy out

Say your body needs 1800 calories, and you only eat 1300 calories. Weight loss will occur because your body uses roughly 500 calories of body fat to cover the missing 500 calories from your diet:

Energy stored = energy in – energy out
-500 = 1300 – 1800

This leads to a theoretical weight loss of 1 lb. per week (3500 kcal per pound of fat).

If you ate 1300 calories on keto and lost 2 lbs. in a week, you would have to use 1000 calories from fat stores. That means that 1000 calories of expended energy are external of your diet a day, for 7 days. If that isn’t the case, the formula does not work.

Energy stored = energy in – energy out
-1000? = 1300 – 1800

This fails basic mathematics.

It just does not work in math, and it also does not work in physics. For keto, or any diet for that matter, to lead to more weight loss – you must get to a higher energy expenditure of calories for it to hold true. This means increasing your metabolic rate, increasing activity levels, etc.

Energy stored = energy in – energy out
-1000 = 1800 – 2800

So, how many calories should you eat? Obviously, that will be different from person to person based on current weight and the current state of their endocrine system. To be short, you never want to go into a caloric deficit that is lower than your fat stores can handle.

How many calories are covered by your fat stores? You can get about 31.4 calories per pound of fat per day. That means if you are 220 lbs. (162 lean mass, 58 lbs. fat) you can get about 1821 calories from fat stores.

Image by Chuk Yong from Pixabay