How many calories do I need?

There are 3 different ways to look at this question of "how many calories do I need?"

The accurate way, the easy way and the inaccurate way.

The inaccurate way:

Your body needs 1200 calories per day to get all the requisite essential vitamins and minerals. You should never go below that amount of calories during a weight loss period. It is not healthy.

With that said, there are communities whose members believe that if you eat a maximum of 1000 calories per day you will live longer. I would not recommend such a low calorie intake.

The accurate way:

There are two components that allow you to accurately compute your body's energy expenditure. Once you know how much energy (calories) you are expending, you will know how many calories you need to replace.

By adding together your basal metabolic rate (BMR) and energy expended during physical activity, you can accurately determine how many calories your body requires each day.

BMR: is also called "rest metabolic rate". Most of your body's energy, about 60-70%, is expended in supporting the ongoing metabolic work of your body's cells. This includes activities such as heart beat, respiration and maintaining body temperature.

To calculate your BMR:

Adult males:  66 ( 6.23 x weight in pounds ) ( 12.7 x height in inches ) - ( 6.8 x age in years )

Adult females:  665 ( 6.23 x weight in pounds ) ( 12.7 x height in inches ) - ( 6.8 x age in years )

In Metric:

Adult males:  66 ( 13.7 x weight in kilos ) ( 5 x height in cm ) - ( 6.8 x age in years )

Adult females: 65 ( 9.6 x weight in kilos ) ( 1.8 x height in cm ) - ( 4.7 x age in years )

Now to get your rest metabolic rate, you need to adjust your BMR calculation by multiplying your BMR figure by the factors below to take into account your level of activity:

Activity Level A: if you exercise lightly = normal daily living, multiply your BMR x 1.3

Activity Level B: if you exercise moderately = 3-4 times per week, multiply your BMR x 1.4

Activity Level C: if you exercise often = more than 4 times per week, multiply your BMR x 1.6

Activity Level D: 1.8 - if you exercise very often = 6-7 times per week for over an hour in each session, multiply your BMR x 1.8

This is called:

Energy Expended during Physical Activity: The second component of the equation depends upon your level of physical activity. Physical activity has a profound effect on human energy expenditure and contributes 20-30% to your body's total energy output. One of the most reliable methods in calculating calories burned during physical activity is the Metabolic Energy (MET) Method.

The Easy Way:

Is this simple formula:

For desk-bound people: Weight x 14 = estimated calories burned per day

For moderately active people: Weight x 17 = estimated calories burned per day

For active people: Weight x 20 = estimated calories burned per day

Note: Moderately Active is defined as 3-4 aerobic sessions per week. Active is defined as 5-7 aerobic sessions per week.