2026 ICD-10-CM Diagnosis Code E56.9

Vitamin deficiency, unspecified

ICD-10-CM Code:: E56.9
ICD-10 Code for:: Vitamin deficiency, unspecified
Is Billable?: Yes - Valid for Submission
Chronic Condition Indicator: ^[1]: Chronic
Code Navigator:

E56.9 is a billable diagnosis code used to specify a medical diagnosis of vitamin deficiency, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2025 through September 30, 2026.

Unspecified diagnosis codes like E56.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Table of Contents

Code Information
Approximate Synonyms
Clinical Classification
Tabular List of Diseases and Injuries
Index to Diseases and Injuries References
Diagnostic Related Groups Mapping
Convert to ICD-9 Code
Patient Education
Other Codes Used Similar Conditions
Code History

Code Classification

Endocrine, nutritional and metabolic diseases
E00–E89
- Other nutritional deficiencies
  E50-E64
  - Other vitamin deficiencies
    E56

Approximate Synonyms

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Acquired ataxia
Acquired ataxia due to vitamin deficiency
Encephalopathy due to vitamin deficiency
Inadequate vitamin intake
Multiple vitamin deficiency disease
Vitamin deficiency
Vitamin deficiency related neuropathy
Vitamin disease

Clinical Classification

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

Nutritional deficiencies

CCSR Code: END007

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

- Avitaminosis (multiple) - See Also: Deficiency, vitamin; - E56.9

- Deficiency, deficient
- - vitamin (multiple) NOS - E56.9

- Encephalopathy (acute) - G93.40
- - in (due to) (with)
  - - lack of vitamin - See Also: Deficiency, vitamin; - E56.9

- Neuroavitaminosis - E56.9

- Polyneuritis, polyneuritic - See Also: Polyneuropathy;
- - due to lack of vitamin NEC - E56.9

- Polyneuropathy (peripheral) - G62.9
- - in (due to)
  - - avitaminosis NEC - E56.9
  - - lack of vitamin NEC - E56.9

Index of External Cause of Injuries

References found for this diagnosis code in the External Cause of Injuries Index:

Avitaminosis(multiple)

Deficiency, deficient

vitamin (multiple) NOS

Encephalopathy(acute)

in (due to) (with)

lack of vitamin

Neuroavitaminosis

Polyneuritis, polyneuritic

due to lack of vitamin NEC

Polyneuropathy(peripheral)

in (due to)

avitaminosis NEC

Polyneuropathy(peripheral)

in (due to)

lack of vitamin NEC

Convert E56.9 to ICD-9-CM

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

Vitamin Deficiency NOS

ICD-9-CM: 269.2

Approximate Flag - The approximate mapping means this ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option, but it may not fully capture the original diagnosis or clinical intent.

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Patient Education

Malnutrition

What is malnutrition?

Malnutrition means that your body isn't getting enough calories or the right balance of nutrients to stay healthy. This can happen if you don't get enough protein, carbohydrates, and fats, eat too much unhealthy food, or don't get the vitamins and minerals your body needs.

Malnutrition can affect people of all ages, but children, older adults, and people with chronic (long-term) health problems have a higher risk.

What are the types of malnutrition?

Most people think of undernutrition with malnutrition. But malnutrition can refer to undernutrition, overnutrition, or an imbalance of nutrients.

Types of malnutrition include:

Protein-energy undernutrition, also called macronutrient undernutrition, happens when your body doesn't get enough protein or calories from food. Two serious forms of this are kwashiorkor and marasmus.
An imbalanced nutritional status occurs when you are not getting the right mix of nutrients. You may get enough calories, but not enough vitamins or minerals.
Vitamin deficiency diseases happen when your body doesn't get enough of certain vitamins. Without the right vitamins, your body cannot stay healthy and may develop specific diseases. For example, scurvy can develop from too little vitamin C, rickets from too little vitamin D, and anemia from too little iron or vitamin B12.
Failure to thrive occurs when children don't gain weight or grow as expected. This may be due to not getting enough food, trouble absorbing nutrients, or other health problems.
Overnutrition can occur when your body gets too many calories or nutrients. This may lead to obesity or other health issues.

What causes malnutrition?

Malnutrition may occur for many reasons, including:

An unbalanced diet that lacks variety or specific nutrients.
Some medical issues, which could include malabsorption syndromes, dementia, eating disorders, depression, alcohol use disorder (AUD), or cancer.
Problems with swallowing, digestion, or dental issues.
Certain medicines that affect how food tastes and smells.
Not being able to get food or cook due to things such as chronic illness, mobility issues, or low income.

Who is at risk for developing malnutrition?

Malnutrition can affect anyone, but some people have a higher risk than others. This includes people who:

Don't have enough knowledge about nutrition
Don't have access to a variety of food
Are older adults or children
Have a low income
Have a chronic (long-term) illness

What are the symptoms of malnutrition?

The symptoms of malnutrition can vary. You may have no symptoms, but if you do, they may include:

Fatigue and weakness
Dizziness
Losing weight without trying
Low body weight
Slow growth or development in children
Frequent infections or slow healing
Dry skin or brittle hair and nails
Swelling in the legs, feet, or belly

How is malnutrition diagnosed?

To check for malnutrition, your provider may:

Do a nutritional screening, which may include questions about weight loss, changes in your appetite, and your ability to eat.
Do a physical exam and order blood tests to check for signs that you don't have enough nutrients.
Refer you to other providers that specialize in nutrition, such as a dietician.

What are the treatments for malnutrition?

Treatment for malnutrition may include improving your diet, replacing missing nutrients, and treating the underlying cause.

Can malnutrition be prevented?

To help prevent malnutrition, eat a healthy diet with many different foods. Talk with your provider if you are worried about your diet, weight loss, or your child's growth.

[Learn More in MedlinePlus]

Vitamins

Vitamins are substances that your body needs to grow and develop normally. There are 13 vitamins your body needs. They are:

Vitamin A
B vitamins (thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B-6, vitamin B-12 and folate)
Vitamin C
Vitamin D
Vitamin E
Vitamin K

You can usually get all your vitamins from the foods you eat. Your body can also make vitamins D and K. People who eat a vegetarian diet may need to take a vitamin B12 supplement.

Each vitamin has specific jobs. If you have low levels of certain vitamins, you may get health problems. For example, if you don't get enough vitamin C, you could become anemic. Some vitamins may help prevent medical problems. Vitamin A prevents night blindness.

The best way to get enough vitamins is to eat a balanced diet with a variety of foods. In some cases, you may need to take vitamin supplements. It's a good idea to ask your health care provider first. High doses of some vitamins can cause problems.