How Many calories do you need each day?

This is a good question. The number of calories that you need every day just to survive is called your maintenance level, or you Total Daily Calorie Expenditure. Just by sitting on the couch and resting you are still burning calories. In a 24-hour period you will burn a certain number of calories on average. This maintenance level is where the number of calories that you burn is exactly equal is the number of calories consumed.

A lot of researches by exercise physiologist have come up with”average” daily calorie expenditure.

For women the average is 2100 cal per day.
For men for men the average is 2700-2900 cal per day.

It is also important that you understand the word ‘average’ here. These figures are estimates and are to be used as a guide, and not as a hard and fast fact for every person in the world. Circumstances different to each person ensure that these averages don’t always apply to everyone.

For example: an elite athlete could expel anywhere from 3500-5000 cal per day depending on their training regime.

To determine the number of calories for you personally or your TDEE, you first need to calculate your ‘basal metabolic rate (BMR)’.  

By definition, the BMR is “The measurement of energy required to keep the body functioning at rest”.

That means if you were to sit on a couch for 24hrs straight, the rate at which your body burns calories is your BMR.

The Harris Benedict formula is one of the most accurate for this calculation, as it takes into account many factors.

Man: BMR = 66+ (13.77 x  weight in kilograms) + ( 5 x height cms) – (6.8 x age in years)

Women: BMR = 655+ (9.6 x  weight in kilograms) + ( 1.8 x height cms) – (4.7 x age in years)

Example

Man, 25 years old, you are 5’11” tall (180 cm), you have a 84 kg, and you have a desk job

BMR = 66 + (13.77X 84) + (5X180)-(4.7X25)
BMR = 66+ 1156.68 + 900 – 117.5

BMR = 2005.18

Now you know you’re basal metabolic rate you can calculate your TDEE by multiplying BMR with the following activity factor

Sedentary = BMR x1.2            (little or no exercise)
Light activity = BMRx1.375            (light exercise/sports – 1.3 days per week)
Mod. Active = BMRx1.55            (moderate exercise 3-5 days per week)
Very Active = BMRx1.725            (hard ex/sports 6-7 days per week)
Extra active = BMRx1.9            (hard daily exercise, 2 x day training)

To continue from the following example

BMR X Activity Level
2005.18 X 1.2 = 2406.22

What this means is every day you need to consume 2406.22 cal in order to maintain your body fat level. The fact that your activity level, being a desk job is taken into account, is the reason for the slightly higher calorie needs.

Remember, your BMR only gives you your calorie needs if you were to stay on the couch for 24hrs straight. Given that you even have a desk job, there is still movement factors involved, including but not limited to get to and from work, walking around the office, using your brain to work etc etc etc.

So to reduce your weight you need to eat fewer calories than 2406.22 and to gain weight you need to eat more calories than 2406.22.

So why not just cut out 500 cal? Although this would work it could send your body into starvation mode. And as described earlier, when your body goes into starvation mode, your metabolism decreases or slows down; therefore you would need fewer calories per day to survive.

The best method to work out how many calories you need to decrease your daily intake by is the percentage method. For optimal and safe fat loss a percentage reduction of 15-20% less calories than your TDEE needs every day is optimum for a healthy weight loss regime.

So for the above example a safe weight loss regime would be reducing the calorie intake of 15% of 2406.22 cal which equals 361 cal.

So our 25-year-old male who wanted to lose body fat would reduce his calorie intake to 2045 cal per day. This accompanied with an exercise regime later explained will be the optimum way for him to lose weight safely.

The last part I will say on calories is that  “calorie counting is necessary”.  For you to lose weight you must eat fewer calories than you burn safely. I can’t stress that enough.