To use Weight2Weight, use the preference panel to select English or Metric units. Then select either male or female sex and an appropriate activity level. Select one of the options for Cal/day/lb. If [Custom] is selected, enter a value for Cal/day/lb. Click [Save] to retain any new selections, or [Restore] followed by [Save] to return to the default values of "English", "Male", "v.Sedentary" and "AmerHrtAssn."

BMI is considered a better way to assess one's weight versus weight alone.It is obtained by dividing weight in kilograms by height in meters squared (or weight in pounds divided by height in inches squared multiplied by 703). A BMI between 20 and 25 is deemed "desirable", while a BMI below 20 is "underweight", between 25 and 30 is "overweight", and 30 and above is "obese." Weight2Weight calculates BMI for the different displayed body weights.

Enter your height in inches (or centimeters), and your current and desired New weight in pounds (or kilograms) and in the three red entry fields in the main window. If either [HarBenMcArd] or [MifflinStJeor] Cal/day/lb is selected, enter Age in years in the last red entry field. Click on the [Calculate all] button to display the Calories/day required to sustain these weights with their associated Body Mass Indices and the weight and Calories/day differences.

Clicking the Sex, Activity level or Cal/day/lb preferences will automatically update the calculations in the main window using the currently displayed preferences and values.

An error message is displayed above the top input row when the inputs for a calculation need correcting. The [Clear all] button clears all input and display fields.

Sample Calculations:

Example 1. Set the preferences to [English] units, [Female] sex, [AmerHrtAssn] Cal/day/lb and [m.Active] activity level using the Preferences panel. Note that the Cal/day/lb selection should be made before selecting the Activity level, since each Cal/day/lb option has its own set of Activity levels. Enter "150.0" for [Current weight], "130.0" for [New Weight], and "64.0" for [Height]. Note that the American Heart Association calculations do not use [Age] as a factor.

Click the [Calculate All] button to show 2025 Calories/day required to maintain the present 150 lb weight. The selected Preferences results in a basal Calories/day/Lb of 13.50. The current BMI is 25.7. It will require 1755 Calories/day to maintain the desired 130 lb New weight. The BMI at the lower weight is 22.3. The weight difference is 20 lbs and 270 fewer Calories/day are requred to maintain a weight of 130 lbs.

Figure 2. Results from Example 1

Example 2. Set the preferences to [Metric] units, the Cal/day/lb preference to [Custom] and enter "18.5" for the Custom [Cal/day/lb]. Enter "65" for [Current weight], "55' for [New weight] and "160" for [Height]. Note that Sex, Activity level and Age are not used when a custom Cal/day/lb factor is selected.

Click the [Calculate all] button to show 2651 Calories/day required to maintain the present 65 kg weight at 18.5 Calories/day/lb. The current BMI is 25.4. It will require 2243 Calories/day to maintain the 55 kg New weight. The BMI at the lower weight is 21.5. The weight difference is 10 kg and 408 fewer Calories/day are requred to maintain 55 kg weight.

Figure 3. Results from Example 2