Nutrition · Moderate evidence
Estimating energy expenditure
The Mifflin-St Jeor equation is the most accurate formula for estimating resting energy expenditure, but it still errs in a significant portion of individuals.
Validation study and systematic review · 2 sources · 2 min
What the studies show
- Mifflin-St Jeor predicted resting energy expenditure within 10% in more individuals than Harris-Benedict and other equations.
- No equation is reliable for all individuals.
- Activity factors introduce more uncertainty than the formula itself.
How Letz applies it
The initial target uses Mifflin-St Jeor with an activity factor and is replaced by adaptive TDEE as soon as there is sufficient weight and intake data.
Who it applies to
Healthy adults with and without obesity.
Limits
The formula is off by more than 10% in about a quarter of people; tracking weight and intake history corrects better than any equation.
Sources
- Mifflin et al., American Journal of Clinical Nutrition, 1990 DOI 10.1093/ajcn/51.2.241
- Frankenfield, Roth-Yousey & Compher, Journal of the American Dietetic Association, 2005 DOI 10.1016/j.jada.2005.02.005
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