The Harris–Benedict equation (also called the Harris-Benedict principle) is a method used to estimate an individual's
basal metabolic rate
Basal metabolic rate (BMR) is the rate of energy expenditure per unit time by endothermic animals at rest.. In other words it is the energy required by body organs to perform normal It is reported in energy units per unit time ranging from watt ( ...
(BMR).
The estimated BMR value may be multiplied by a number that corresponds to the individual's activity level; the resulting number is the approximate daily
kilocalorie
The calorie is a unit of energy that originated from the caloric theory of heat. The large calorie, food calorie, dietary calorie, kilocalorie, or kilogram calorie is defined as the amount of heat needed to raise the temperature of one liter of w ...
intake to maintain current
body weight
Human body weight is a person's mass or weight.
Strictly speaking, body weight is the measurement of mass without items located on the person. Practically though, body weight may be measured with clothes on, but without shoes or heavy accessori ...
.
The Harris-Benedict equation may be used to assist weight loss — by reducing the kilocalorie intake number below the estimated maintenance intake of the equation.
Calculating the Harris-Benedict BMR
The original Harris–Benedict equations were published in 1918 and 1919.
The Harris–Benedict equations revised by Roza and Shizgal in 1984.
The 95% confidence range for men is ±213.0 kcal/day, and ±201.0 kcal/day for women.
The Harris–Benedict equations revised by
Mifflin and St Jeor in 1990:
History
The Harris-Benedict equation sprang from a study by
James Arthur Harris and
Francis Gano Benedict, which was published in 1919 by the
Carnegie Institution of Washington
The Carnegie Institution for Science, also known as Carnegie Science and the Carnegie Institution of Washington, is an organization established to fund and perform scientific research in the United States. This institution is headquartered in W ...
in the
monograph
A monograph is generally a long-form work on one (usually scholarly) subject, or one aspect of a subject, typically created by a single author or artist (or, sometimes, by two or more authors). Traditionally it is in written form and published a ...
br>
A Biometric Study Of Basal Metabolism In Man A 1984
revision improved its accuracy. Mifflin et al. published an equation more predictive for modern lifestyles in 1990.
[ Later work produced BMR estimators that accounted for lean body mass.
]
Issues in dietary use
As the BMR equations do not attempt to take into account body composition, identical results can be calculated for a very muscular person, and an overweight person, who are both the same height, weight, age and gender. As muscle and fat require differing amounts of calories to maintain, the TEE estimates will not be accurate for such cases.
The paper behind the latest update (Mifflin et al) to the BMR formula states all participants in their study fall within the 'normal' and 'overweight' body mass index
Body mass index (BMI) is a value derived from the mass (Mass versus weight, weight) and height of a person. The BMI is defined as the human body weight, body mass divided by the square (algebra), square of the human height, body height, and is ...
(BMI) categories, and so the results also do not necessarily apply to those in the 'underweight' or 'obese' BMI categories.
See also
* Food energy
Food energy is chemical energy that animals and humans derive from food to sustain their metabolism and muscular activity.
Most animals derive most of their energy from aerobic respiration, namely combining the carbohydrates, fats, and protein ...
* Resting metabolic rate
Resting metabolic rate (RMR) refers to whole-body mammal (or other vertebrate) metabolism during a time period of strict and steady ''resting conditions'' that are defined by a combination of assumptions of physiological homeostasis and List of typ ...
* Institute of Medicine Equation
* Schofield equation
Cited sources
External links
About.com's BMR Calculator
Calorie Calculator
{{DEFAULTSORT:Harris-Benedict equation
Nutrition
Equations
Mathematics in medicine