Basal Metabolic Rate
Your basal metabolic rate (BMR) describes the minimum amount of calories your body will spend each day to exist. The Mifflin St Jeor equation estimates your BMR in kcal/day:
BMR = (10*M + 6.25*H - 5.0*A) + S
BMR = (10*M + 6.25*H - 5.0*A) + S
- M is mass in kilograms
- H is height in centimeters
- A is age in years
- S is +5 for males and -151 for females
Total Daily Energy Expenditure
Total daily energy expenditure (TDEE) describes the total amount of calories your body will spend each day, including your BMR and additional calories burned from movement. According to the Harris-Benedict equation,
a sedentary person's TDEE will be approximately equal to BMR x 1.2.
To lose weight, consume less calories than your TDEE. One pound of fat = 3500 kcal, so eating at a 500 kcal deficit will lead to ~1 lb of weight loss per week (note that this estimation does not consider the loss of lean body mass and/or water weight).
NOTE: Since the terms "light exercise", "moderate exercise", etc. are arbitrary, the calculator will only provide the "little to no exercise" (BMR x 1.2) base value as it makes the least assumptions. You should calculate calories burned from any exercises separately and add it to this value to approximate your true energy expenditure for the day.
To lose weight, consume less calories than your TDEE. One pound of fat = 3500 kcal, so eating at a 500 kcal deficit will lead to ~1 lb of weight loss per week (note that this estimation does not consider the loss of lean body mass and/or water weight).
NOTE: Since the terms "light exercise", "moderate exercise", etc. are arbitrary, the calculator will only provide the "little to no exercise" (BMR x 1.2) base value as it makes the least assumptions. You should calculate calories burned from any exercises separately and add it to this value to approximate your true energy expenditure for the day.
| Harris-Benedict BMR Modifiers | |
|---|---|
| Little to no exercise | TDEE = BMR x 1.2 |
| Light exercise (1–3 days per week) | TDEE = BMR x 1.375 |
| Moderate exercise (3–5 days per week) | TDEE = BMR x 1.55 |
| Heavy exercise (6–7 days per week) | TDEE = BMR x 1.725 |
| Very heavy exercise (twice per day) | TDEE = BMR x 1.9 |
Body Mass Index
Body mass index (BMI) is a calculation based on body mass and height.
According to the CDC, "BMI does not measure body fat directly, but research has shown that BMI is moderately correlated with more direct measures of body fat obtained from skinfold thickness measurements, bioelectrical impedance, densitometry (underwater weighing), dual energy x-ray absorptiometry (DXA) and other methods. Furthermore, BMI appears to be as strongly correlated with various metabolic and disease outcome as are these more direct measures of body fatness. In general, BMI is an inexpensive and easy-to-perform method of screening for weight category, for example underweight, normal or healthy weight, overweight, and obesity."1
NOTE: BMI is calculated from mass and height. It does not differentiate between whether the mass comes from body fat or muscle, and therefore may not be a useful metric for bodybuilders or trained athletes.2
According to the CDC, "BMI does not measure body fat directly, but research has shown that BMI is moderately correlated with more direct measures of body fat obtained from skinfold thickness measurements, bioelectrical impedance, densitometry (underwater weighing), dual energy x-ray absorptiometry (DXA) and other methods. Furthermore, BMI appears to be as strongly correlated with various metabolic and disease outcome as are these more direct measures of body fatness. In general, BMI is an inexpensive and easy-to-perform method of screening for weight category, for example underweight, normal or healthy weight, overweight, and obesity."1
NOTE: BMI is calculated from mass and height. It does not differentiate between whether the mass comes from body fat or muscle, and therefore may not be a useful metric for bodybuilders or trained athletes.2
| BMI | Weight Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 - 24.9 | Normal Weight |
| 25 - 29.9 | Overweight |
| 30 and Above | Obese |