Undernutrition

Definition

Undernutrition is a state of insufficient nutrient intake relative to physiological needs, resulting in weight loss, stunted growth, or micronutrient deficiencies. It represents inadequate consumption of calories and essential nutrients.

How it works

Undernutrition develops when dietary intake fails to meet the body's energy and nutrient requirements for maintenance and health. This can result from insufficient food availability, poor dietary choices, digestive disorders, or increased metabolic demands. In children, undernutrition leads to stunting (low height for age) and wasting (low weight for height), impairing physical and cognitive development. In adults, it causes weakness, reduced work capacity, and compromised immune function. Acute undernutrition can develop rapidly, while chronic undernutrition builds gradually over time.

Role

Indicates dietary insufficiency requiring urgent nutritional rehabilitation and addressing food security or medical barriers to adequate intake.

Examples

• Child in food-insecure region with inadequate calories
• Person with persistent diarrhea losing nutrients
• Adolescent athlete with insufficient energy intake
• Patient with swallowing difficulties consuming minimal food

Recommendations

Increase nutrient-dense food intake progressively, address underlying causes such as food insecurity or malabsorption, and monitor nutritional status through weight and biochemical markers. Provide nutritional education and access to adequate food supplies.

Key takeaway

Undernutrition is preventable and reversible through adequate food access and targeted nutritional intervention.

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