Fats serve as energy stores for the body. Let's say you need 3000 calories per day to maintain your current weight. But instead of eating 3000 calories, you eat only 2500 calories per day. Now your body burns your body fat to generate energy which is equal to 500 calories, because you need another 500 calories for your daily activities. That's how we lose weight(fat) by reducing calories in our diet. 3500 calories is the rough estimate for the energy contained in one pound of fat. That means when 3500 calories are generated, one pound of fat is burnt. Now let's say you maintain the above 2500 calorie diet for a week. Now your body has generated 500 x 7=3500 calories from your body fat through out the week. Therefore you have lost one pound of fat(i.e one pound of weight!).
This is simple.First you have to calculate your BMR.Then you can calculate your TDEE using the Harris-Benedict Principle. Choose your activity level from the following and calculate your daily calorie need. Little to no exercise: Calories you need per day to maintain your current weight=BMR x 1.2 Light exercise (1–3 days per week): Calories you need per day to maintain your current weight=BMR x 1.375 Moderate exercise (3–5 days per week): Calories you need per day to maintain your current weight=BMR x 1.55 Heavy exercise (6–7 days per week): Calories you need per day to maintain your current weight=BMR x 1.725 Very heavy exercise (twice per day, extra heavy workouts): Calories you need per day to maintain your weight=BMR x 1.9 Too Lazy?Here's a tool to calculate the amount of calories you need per day to maintain your current weight (i.e Your TDEE). Related: How to calculate my BMR What is TDEE - Total Daily Energy Expenditure What is BMR - Basal Metabolic Rate
TDEE is the total number of calories your body burns in a day, including the calories burned in all the activities you do. This is the amount of calories you need per day to maintain your current weight. You can calculate your TDEE by using the value you obtained for your BMR. Related: How to calculate my BMR What is BMR - Basal Metabolic Rate How can I calculate my TDEE
In scientific circles, 1 kilocalorie = 1000 calories. But generally when we are talking about weight loss and weight gain or when we read food labels CALORIES is an abbreviation for KILOCALORIES.
You can calculate your BMR using The Harris-Benedict equation. For Men: BMR = 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) – ( 6.76 x age in years ) For Women: BMR = 655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) – ( 4.7 x age in years ) Ex:Let's say you're a 20 year old woman whose weight is 120lbs and height is 60 inches. Then your BMR = 655 + ( 4.35 x 120) + ( 4.7 x 60 ) – ( 4.7 x 20 ) = 1365 calories. According to this equation we can see that your BMR changes as you gain or lose weight(And also with your age).Therefore it is recommended to calculate your BMR every time your weight changes.And also please bear in mind that this is just a rough estimate and if you are too fat or too muscular these numbers may be inaccurate.So please consult a physician and/or specialist to measure your BMR accurately, before taking any actions. Related: What is BMR - Basal Metabolic Rate
