About the Basal Metabolic Rate
The basal metabolic rate (BMR) is the daily expenditure of energy of a human, at rest. It is commonly represented in kilo-calories per day.
BMR may also be used to estimate the total caloric expenditure when adjusted for the activity level of the individual. The adjustment proposed by the UN Food and Agriculture Organization is to multiply the BMR by a factor representative of the physical activity level (PAL) of the individual.
The proposed factor is:
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Sedentary or light physical activity: 1.53
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Active individuals: 1.76
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Vigorously active individuals: 2.25
Calculation
This calculator uses a modified version the Harris-Benedict equation to estimate BMR. The H-B equation was published in 1918-1919 and has proven to provide fairly accurate results. It was later improved by Roza and Shizgal in 1984, which is the version used by our calculator.
The formulas used by our calculator are:
| Gender | Formula |
| Men | 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years) |
| Women | 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years) |
Because the Harris Benedict equation does not take into account the body composition (for example the body fat %) it may not be accurate for some cases. For instance, a high body fat individual with the same weight of a muscular individual will result in similar BMR estimates, however the muscular individual will in fact have a higher BMR.
For more info on BMR: https://en.wikipedia.org/wiki/Basal_metabolic_rate
For more info on the Harris–Benedict equation for BMR estimation: https://en.wikipedia.org/wiki/Harris-Benedict_equation