Weight Loss is a Simple(ish) Formula

Step 1: 

Calculate your daily Basal Metabolic Rate (BMR), or how many calories you would burn doing absolutely nothing all day:

Women
BMR = 655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years )

Men
BMR = 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) - ( 6.8 x age in year )

Step 2: 

Calculate how many calories you burned in total during the day while both sedentary (BMR) and through exertion (exercise), subtracting a minute's worth of BMR for every minute spent exercising (so those minutes aren't counted twice):

Total Calories Burned = BMR - ((BMR/1440) * minutes spent exercising) + calories burned exercising.

We adjust the daily BMR by subtracting a minute's worth of BMR calories for every minute spent exercising, so that those minutes aren't double counted. To do this we divide the BMR by 1440 (the number of minutes in a day) to figure out what our BMR per minute is, and then multiply it by the number of minutes spent exercising. Then, we subtract this number from the daily BMR, and finally add the number of calories burned during exercise to get our total calories burned for the day.

Step 3:

We subtract Total Calories Burned from the number of calories you've taken in during the day via food and drink.

Calories In - Calories Burned = Net Calories


If your Net Calories figure isn't negative, you won't lose weight. If it is, you will. It's as simple as that. The more negative it is, the faster you'll lose weight. The more positive it is, the faster you'll gain weight.