Adjusted Body Weight

For clinical nutrition calculations in patients with obesity, where actual body weight overestimates metabolically active mass and IBW underestimates it.

Reviewed by Pooja V. Menon, Registered Dietitian · Last updated

How it’s computed

AdjBW = IBW + factor × (Actual − IBW), applied when actual weight is > 125 % of IBW. Below that threshold, use actual body weight directly.

IBW here uses the Devine formula (Men: 50 + 2.3 × [height in inches − 60]; Women: 45.5 + 2.3 × [height in inches − 60]), the convention used in most clinical nutrition and drug-dosing references.

When to use AdjBW

  • Energy (kcal) estimations in adults with obesity — actual weight overestimates resting energy expenditure; IBW underestimates.
  • Protein requirements in adults with obesity (e.g., ASPEN critical-care guidance suggests high-protein hypocaloric feeding using AdjBW or IBW-based targets).
  • Some drug dose calculations where lean body mass matters (use with caution — drug-specific references supersede).

Sources

  • Mueller CM, ed. The ASPEN Adult Nutrition Support Core Curriculum. American Society for Parenteral and Enteral Nutrition, 3rd ed. 2017.
  • Choban P, Dickerson R, Malone A, et al. ASPEN Clinical Guidelines: Nutrition support of hospitalized adult patients with obesity. JPEN 2013;37(6):714–44.
  • Wilkens Parrish C, et al. Dosing in obesity: a simple solution to a big problem. Nutr Clin Pract 2007.
  • Erstad BL. Dosing of medications in morbidly obese patients in the intensive care unit setting. Intensive Care Med 2004;30(1):18–32.