Resting Energy Expenditure (Mifflin–St Jeor)

What is this formula?

The Mifflin–St Jeor equation estimates Resting Energy Expenditure (REE), which is the amount of energy a person expends while at rest under normal living conditions. It is one of the most widely used equations in modern clinical nutrition and dietetics.

When to use it

Use this formula to estimate calorie requirements for nutrition planning, weight management, obesity treatment, fitness programs, and clinical dietary assessments.

Example

A woman is 35 years old, weighs 65 kg, and is 165 cm tall.

Data:

W = 65 kg

H = 165 cm

A = 35 years

Formula:

REE = 10W + 6.25H − 5A − 161

Substitution:

REE = (10×65) + (6.25×165) − (5×35) − 161

REE = 1345.25 kcal/day

Result:

Resting energy expenditure ≈ 1345 kcal/day

Applications

- Clinical nutrition

- Weight-loss programs

- Sports nutrition

- Dietary planning

- Obesity management

- Metabolic assessment

- Public health nutrition

Note

The Mifflin–St Jeor equation is an empirical predictive model developed from human population studies. It generally provides more accurate estimates for modern populations than the original Harris–Benedict equation, although direct calorimetry remains the reference standard. Accuracy may vary depending on body composition, age, ethnicity, and health status.