The duration of a weight-loss diet can be estimated based on the amount of fat to be lost and the daily reduction in calories.
Prerequisite: stable lifestyle with a regular diet and physical activity
Goal: to estimate the length of time needed to lose a specified amount of fat
Parameters:
(1) amount of fat mass to be lost in kilograms
(2) number of kcal reduced by day in diet
(3) number of additional kcal consumed by increased physical activity or exercise
number of kcal represented by the fat mass =
= (fat in kg) * (1000 g/kg) * (9 kcal per g fat)
total reduction in kcal per day =
= (number of kcal reduced from diet) + (number of kcal from exercise)
number of days required to lose fat =
= (total kcal from fat) / (total reduction in kcal per day)
Alternatively:
number of kcal needed to be reduced each day =
= (total kcal from fat) / (number of days to achieve desired weight loss)
