ICD-10-CM 2027
ICD-10 code for diet deficiency
From the official ICD-10-CM alphabetic index entry “Deficiency, deficient › diet”. Page updated September 29, 2026.
About coding diet deficiency
The ICD-10-CM code for diet deficiency is E63.9 (Nutritional deficiency, unspecified).
Within E63, choose E63.9 (Nutritional deficiency, unspecified) only when documentation doesn't support a more specific option: essential fatty acid [EFA] deficiency (E63.0), Imbalance of constituents of food intake (E63.1) and other specified nutritional deficiencies (E63.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 640 (Miscellaneous Disorders of Nutrition, Metabolism, Fluids and Electrolytes with MCC, relative weight 1.3395) and DRG 641 (Miscellaneous Disorders of Nutrition, Metabolism, Fluids and Electrolytes without MCC, relative weight 0.7865), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about diet deficiency ICD-10 codes
What is the ICD-10 code for diet deficiency?
- E63.9 — Nutritional deficiency, unspecified.
Is E63.9 billable?
- Yes. E63.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can E63.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict E63.9 as a principal diagnosis.
Is E63.9 a CC or MCC?
- No. E63.9 is neither a CC nor an MCC under MS-DRG v44.0.