Step one is to calculate your BMR with the following formula:

Women:

655 + (4.3 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)

Men:

66 + (6.3 x weight in pounds) + (12.9 x height in inches) - (6.8 x age in years)

Please note that this formula applies only to adults.

Calculate Activity

Step two: In order to incorporate activity into your daily caloric needs, do the following calculation:

If you are sedentary : BMR x 20 percent

If you are lightly active: BMR x 30 percent

If you are moderately active (You exercise most days a week.): BMR x 40 percent

If you are very active (You exercise intensely on a daily basis or for prolonged periods.): BMR x 50 percent

If you are extra active (You do hard labor or are in athletic training.): BMR x 60 percent

Add this number to your BMR.

The result of this formula will be the number of calories you can eat every day and maintain your current weight. In order to lose weight, you’ll need to take in fewer calories than this result.

As you lose weight, you can re-calculate the formula to assess your new BMR.

Create a Calorie Deficit

In order to lose weight, you must create a calorie deficit. It is easier and healthier to cut back your calorie intake a little bit at a time. Every 3,500 calories is equivalent to one pound.

So, if you cut back 500 calories a day, you should lose about one pound per week. That said, If you exercise to burn off 500 calories a day you should lose approximately one pound per week. Do both, and … you get the picture. Ideally, you should do a combination of both, (such as cut back 250 calories; burn an extra 250 calories).

Your weight loss will vary from week to week and at times you may even gain a little weight — if you’re working out you could be developing muscle, which weighs more than fat.

The long-term results are what matters.

Never cut back to fewer than 1,200 daily calories without medical supervision.

(Source: health-heaven)