Apply the anthropometric and clinical findings to visualize the overall malnutrition risk score.
Guidelines & Evidence
Clinical Details
Section 1
When to Use
When to Use
Universal nutritional screening at hospital admission or primary care visit
To identify adults at risk of malnutrition (under-nutrition)
Applicable to all adult patients across hospital, community, and care home settings
Philosophy of MUST
The MUST score focuses on current nutritional status (BMI), recent weight stability, and the impact of acute disease on future intake. It is the most widely validated tool for identifying early malnutrition risk.
Section 2
Formula & Logic
The 3 Scoring Steps (0–2 pts each)
01
Step 1: Body Mass Index (BMI). Score 0 if > 20; 1 if 18.5–20; 2 if < 18.5.
02
Step 2: Weight Loss (Unplanned in 3–6 months). Score 0 if < 5%; 1 if 5–10%; 2 if > 10%.
03
Step 3: Acute Disease Effect. Add 2 points if the patient is acutely ill AND there has been or is likely to be no nutritional intake for > 5 days.
Risk Groups
Score 0
Low Risk
Score 1
Medium Risk
Score ≥ 2
High Risk
Section 3
Pearls/Pitfalls
Predicting Outcomes
Malnutrition is not just a secondary finding; it is a primary driver of poor surgical outcomes, increased length of stay, and higher mortality. Patients with a "High Risk" MUST score are statistically significantly more likely to develop hospital-acquired infections or pressure ulcers.
Acute Disease — The Power of 5 Days
The "Acute Disease" modifier (Step 3) is frequently missed. In a septic or post-operative patient, the 2-point addition often correctly identifies them as "High Risk" even if their current BMI is normal.
Clinical Pearls
For patients who cannot be weighed, mid-upper arm circumference (MUAC) and subjective assessments can be used to estimate BMI category
Weight loss > 10% in 6 months is one of the "Global Leadership Initiative on Malnutrition" (GLIM) phenotypic criteria for malnutrition
Screening should be repeated weekly for hospitalized patients to track nutritional decline
Developed by the Malnutrition Advisory Group (MAG) of BAPEN (British Association for Parenteral and Enteral Nutrition). It was created to provide a single, universal tool that could transition with the patient between hospital and home.
