Here's an easy formula for estimating calories needed to lose weight safely every week (1/2-2 pounds).

Ask yourself these questions:

1. What's your weight loss goal?

To find a healthy weight loss goal, try using Health Status' Ideal Body Weight Calculator.

2. What are your physical activity levels?

If you exercise three or four times per week for one hour, multiply your goal weight by 15. If you don't exercise at all, multiply by 13, and if you work out an hour per day nearly every day, multiply by 20. This is the daily calorie intake you're working toward.

3. How many calories do you need to cut?

Subtract the total from your physical activity levels (calculated in step 2) from the average daily calories you tallied at the end of Week 1. During each of the remaining three weeks of the plan, cut down your daily calories by one-third of this number.

Example: Your goal weight is 135, you haven't been exercising lately and your average daily calorie tally during Week 1 was 2,655: 135 (goal weight) X 13 (activity level) = 1,755 (daily calorie intake at goal weight) 2,655 (daily current calorie intake) - 1,755 (daily calorie intake at goal weight) = 900

Cut one-third of your daily calories (300 calories in this example) each week, starting in Week 2 until you reach the level of calories needed to in Week 4. Your daily calorie intake would then be 2,355 for Week 2; 2,055 for Week 3; and 1,755 calories for Week 4 and beyond.