Lose It! estimates the number of calories you burn each day at rest using a standard formula based on height, weight, age, and gender (the Mifflin equation). This equation produces what is known as a resting metabolic rate (RMR).

The Mifflin equation provides a good approximation of RMR for most people, however individual metabolisms can and do vary. If you feel that your RMR varies from that of the typical person (e.g. because a doctor or nutritionist has more accurately measured your RMR) you may wish to adjust your daily calorie budget accordingly.

Lose It! also assumes that your Personal Activity Level (PAL) is sedentary to light (e.g. a typical office worker). In more technical terms this corresponds to a PAL of 1.45. This PAL corresponds to the following set of daily activities:

If you believe that your PAL is higher or lower based on your actual daily activity level or because you have had your PAL more accurately measured by a doctor or nutritionist you may wish to adjust your daily calorie budget accordingly.

Note that dedicated exercises such as jogging, running, or playing sports are not included in your daily PAL. This is because Lose It! enables you to account for calories burned from these activities explicitly by logging them as exercises.