Malnutrition

Malnutrition refers to deficiencies, excesses, or imbalances in nutrition. While often associated with undernutrition, it also includes micronutrient deficiencies and diet-related chronic disease.

Table of Contents

Quick Facts

  • ICD-10: E40–E46
  • Common in: Older adults, hospitalized patients
  • Reversible: When detected early

Causes

  • Inadequate food intake (food insecurity, eating disorders, dental problems)
  • Malabsorption (celiac disease, IBD, post-surgical)
  • Increased nutrient needs (cancer, severe burns, recovery from surgery)
  • Chronic illness (heart failure, COPD, kidney disease)
  • Dementia and feeding difficulties
  • Depression
  • Medications affecting appetite or absorption

Signs

  • Unintended weight loss
  • Muscle wasting and weakness
  • Fatigue
  • Poor wound healing
  • Frequent infections
  • Dry skin, hair loss, brittle nails
  • Specific deficiency signs (e.g., pale skin in iron deficiency, neuropathy in B12 deficiency)

Diagnosis

  • Nutritional assessment and screening tools (MUST, MNA)
  • Weight history and body composition
  • Blood tests (albumin, prealbumin, vitamin levels)
  • Assessment of underlying causes

Treatment

  • Dietitian-led nutritional plan
  • Oral nutritional supplements
  • Tube feeding or IV nutrition for severe cases
  • Address underlying medical, dental, or social causes
  • Treat depression or cognitive issues affecting intake

When to See a Doctor

See a doctor for unintended weight loss, especially in older adults or people with chronic illness; for persistent fatigue and weakness; or if a loved one is no longer eating well.

Related Conditions

Weight Loss

Common feature

 Loss of Appetite

Frequent contributor

 Anemia

Often related

 Vitamin D Deficiency

A specific deficiency

Frequently Asked Questions

Can someone be overweight and malnourished?

Yes. Excess calorie intake with poor nutrient quality is a form of malnutrition. Micronutrient deficiencies are common even in people with overweight or obesity.

Medical Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about a medical condition. If you are experiencing a medical emergency, call your local emergency number immediately.

References

  • World Health Organization. Malnutrition Fact Sheet.