Which serum lab value best reflects nutritional malabsorption?

• A. Albumin 1.5 g/dL
• B. Calcium 8.5 mg/dL
• C. BUN 20.0 mg/dL
• D. Sodium 148.0 mEq/L

Answer: (A)

Albumin reflects long-term protein status and body protein stores. In nutritional malabsorption, the body isn’t getting or keeping enough amino acids to maintain normal albumin synthesis, so levels fall. An albumin of 1.5 g/dL is markedly low and aligns with protein-energy malnutrition caused by malabsorption.

Other values are less specific to nutrition. Calcium can be affected by vitamin D status and fat malabsorption but isn’t a direct marker of overall malabsorption. BUN depends on protein intake, liver and kidney function, and hydration, not specifically on absorption capacity. Sodium changes reflect fluid balance rather than nutritional status.