For a person to lose weight, she/he must take into account how many calories he ingests during the day. Daily calorie intake is not the same for all people. According to the US Department of Health, adult women need to consume an average of 1600-2400 calories a day, and adult men 2000-3000 calories to maintain weight. Also, physical activity is important, as are many other factors. Factors that affect the number of calories a person needs to stay healthy include age, weight, height, gender, level of physical activity, and general health. The person trying to lose weight must take care of calorie intake so that the body can function normally and have all the necessary nutrients. To begin, we need to consume fewer calories than we expend in total energy. However, not all calories are the same. Calories from nutritious food sources will provide fuel for our activities during the day and will make us in good mood.
To estimate our weight lose plan calorie by hand, we need to follow these steps:
Calculate the basal metabolic rate (BMR) using the Mifflin-St Jeor formulas:
BMR (kcal/day)men = 10 × weight (kg) + 625 × height (m) − 5 × age (y) + 5
BMR (kcal/day)women = 10 × weight (kg) + 625 × height (m) − 5 × age (y) − 165
BMR is the amount of energy a human body uses when it is at rest. In other words, it’s the amount of energy needed to support bodies vital functions: breathing, blood circulation, controlling body temperature, brain, etc.
Calculate the total daily energy expenditure (TDEE) which estimates our total daily energy expenditure, and helps us to find out how many calories we burn every day.
First, choose the index of your physical activity level (PAL) from one of the following:
- little/no exercise: 1.2;
- light exercise 1-2 times/week: 1.375;
- moderate exercise 2-3 times/week: 1.55;
- hard exercise 4-5 times/week: 1.725;
- physical job or hard exercise 6-7 times/week: 1.9;
- professional athlete: 2.4.
Multiply BMR and PAL to determine the total daily energy expenditure, i.e.
TDEE (kcal/day) = BMR × PAL
This is the amount of calories we should eat to maintain your weight.
Finally, to calculate our daily weight loss calorie requirement (WL(i)) in the i-th week, depending on the choice 0.5 kg/per week or 1 kg/per week, we use the following formulas:
– If weight loss pace is 1 kg/per week, then
WGmen(i) = (10 × (weight + i − 1) + 625 × height − 5 × age + 5) × PAL - 1000
WGwomen(i) = (10 × (weight + i − 1) + 625 × height − 5 × age - 161) × PAL - 1000
– If weight loss pace is 0.5 kg/per week, then
WGmen(i) = (10 × (weight +
i − 1
) + 625 × height − 5 × age + 5) × PAL - 500
WGwomen(i) = (10 × (weight +
i − 1
) + 625 × height − 5 × age - 161) × PAL - 500
We can reduce weekly calorie intake by between 3500 to 7000 in one the following ways:
A. Eat 3500 to 7000 fewer calories weekly, i.e. 500 to 1000 fewer calories daily;
B. Burn off 500 to 1000 calories daily through exercise;
C. Combine the previous two items.