Nutrition Assessment
The four assessment domains (ABCD)
Assessment combines anthropometric, biochemical, clinical, and dietary data plus food/nutrition-related history. Screening tools (MUST, MNA, MST) identify risk; they do not diagnose. The nutrition-focused physical exam looks for fat loss, muscle wasting (temporal, clavicular, interosseous), edema, and micronutrient signs (angular stomatitis, koilonychia, glossitis).
Anthropometrics: BMI is a screening measure only - Asian populations use lower cutoffs (overweight ≥23, obesity ≥25 kg/m²); waist circumference adds central-adiposity risk; pediatric growth is judged by z-score and percentile trends on WHO (0–2 y) and CDC (2–20 y) charts. Adjust weight for edema or ascites when estimating dry weight.
Biochemical markers: albumin (half-life ~20 days) and prealbumin/transthyretin (~2 days) fall with inflammation, infection, liver disease, and hydration shifts and are poor stand-alone nutrition indicators. Use CRP to interpret them. Creatinine-height index and nitrogen balance estimate muscle and protein status.
Dietary methods: 24-hour recall (quick, relies on memory, one day is not usual intake), food record (prospective, may alter behavior, needs literacy), FFQ (captures usual intake, recall and portion-estimation error), and diet history. Corroborate any single day with multiple days or a screener.
Rule of thumb (worked): usual weight 80 kg, current 72 kg → 8 ÷ 80 = 10% loss. Unintentional loss >5% in 1 month or >10% in 6 months warrants intervention in most adult settings.