Once you understand the science behind weight loss you know that calories are a hugely important part of it. In fact, your calorie balance is the number one determinant of your diet success and that there are three different states of a calorie balance negative, positive and neutral.
Of course, to reach any of the 3 states you will have to know how many calories your body expands every day. There are several different equations and strategies you can use to calculate this value. Some of them are more or less accurate and more or less difficult than others.
I will now show you the easiest and most straightforward way which is to calculate your TDEE. Your TDEE describes your Total daily energy expenditure, which is the number of calories that your body burns in one day. It is calculated by estimating how many calories you burn while resting (= Basal Metabolic Rate or BMR) and adding a certain number of calories on top, depending on how often you exercise.
If you were to consume roughly the same amount of calories as your TDEE you would be in a neutral calorie balance. If you consumed more calories than your TDEE you would be in a positive calorie balance and If you consumed fewer calories than your TDEE you would be in a negative calorie balance.
The simplest method of calculating your TDEE is by using an online calculator such as the one I linked here. It will ask you for your age, weight, height and weekly exercise. While the result will not be 100% accurate – since we all have different metabolisms and BMRs – it will give you a good idea of how many calories you need to consume in order to maintain your current weight.
If this is not exact enough for you or you feel the value you got from the online calculator is a little off you want to do the following: Use the estimated TDEE value and consume around this number of calories ever day. Next weight yourself twice a week and monitor changes in weight.
If you are losing weight, the estimated TDEE was too low and you should increase it by 100 calories. If you are gaining weight, the estimated TDEE was too high and you should decrease it by 100 calories. Continue this strategy until your weight stagnates which is the point where you have found your true TDEE.
To make thing easier for you let’s take the example of a man who weighs 180lb, is 6 foot (or 180cm) tall and 25 years old. If we assume he trains 3 to 4 times a week at high intensity his TDEE will lie anywhere between 2500 and 2700 calories per day.
You would then start with one of the two values and diet accordingly for about 10 days to two weeks. if after this period you see you are gaining weight you will have to decrease your initial calorie value and if you are losing weight increase it.
Now keep in mind that this value will be a lot lower if you don’t or only rarely exercise. A 180lb, 6-foot man that doesn’t exercise has a TDEE of around 2000 to 2200 calories. This is almost 500 calories less per day. Getting such differences right can make or break your diet.