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How is malnutrition different from undernutrition?

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rickets, a nutritional disease — nutritional disease Children with rickets. The disease, which most commonly strikes children, causes bone deformities such as bowlegs. Rickets is caused by a lack of vitamin D or calcium.

Malnutrition and undernutrition are related but distinct terms in the context of nutritional health.

Malnutrition is a broad term referring to any disorder caused by an improper diet. It encompasses a wide spectrum of conditions resulting from a faulty or inadequate diet, or from a physical inability to absorb or metabolize nutrients. Crucially, malnutrition includes both the lack of sufficient nutrients and the overconsumption of calories, such as obesity, which is a common form of malnutrition in developed nations.12

Undernutrition is a specific subset of malnutrition. It refers to deficient bodily nutrition caused by inadequate food intake or the faulty assimilation of nutrients. Chronic undernutrition often manifests as protein-energy malnutrition (PEM), which includes conditions like marasmus (severe calorie and protein deprivation) and kwashiorkor (protein deficiency).34

In summary, while all undernutrition is a form of malnutrition, not all malnutrition is undernutrition, as the latter term specifically describes states of deficiency rather than the broader range of dietary imbalances.12