What Does a Malnutrition Rash Look Like? Recognizing the Signs of Deficiency

October 7, 2025 •

4 min read

According to the World Health Organization, more than 45 million children are affected by severe acute malnutrition globally, which can manifest in noticeable dermatological signs. Understanding what does a malnutrition rash look like is critical for early identification and treatment, as these skin issues are often a visible cue that the body is missing essential nutrients.

Quick Summary

Nutrient deficiencies can cause distinct skin changes, ranging from flaky 'flaky paint' dermatosis associated with kwashiorkor to the red, symmetrical, and photosensitive rash of pellagra. Zinc deficiency can lead to a characteristic rash around the mouth and extremities, while vitamin C deficiency manifests as red spots from bleeding under the skin. The appearance of a malnutrition rash is a vital sign indicating a serious underlying nutritional imbalance.

Key Points

Flaky 'Peeling Paint' Dermatosis: A classic sign of kwashiorkor, this rash consists of hyperpigmented plaques that peel away to reveal lighter, atrophic skin, primarily on pressure points like the buttocks.
Casal's Necklace in Pellagra: A distinctive, symmetrical, and photosensitive rash caused by niacin deficiency, often appearing as a thick, dark, and scaly collar around the neck.
Periorificial and Acral Rash of Zinc Deficiency: Zinc deficiency, such as in acrodermatitis enteropathica, presents with well-defined, erythematous plaques around the body's openings (mouth, anus) and on the extremities.
Hemorrhagic Spots from Scurvy: Vitamin C deficiency can cause tiny, red or blue spots under the skin (perifollicular hemorrhage) due to weakened blood vessels, alongside bumpy 'chicken skin' and easy bruising.
Seborrheic-Like Dermatitis from B-Vitamins: Deficiencies in certain B-complex vitamins, like B2 and B6, can result in a scaly, greasy rash on the face and other areas, often resembling seborrheic dermatitis.
Diagnosis is Key for Treatment: The appearance of a malnutrition rash is a crucial symptom that requires a medical evaluation to identify the specific nutrient deficiency and begin targeted treatment.

Malnutrition and Its Impact on Skin Health

Proper nutrition is fundamental to maintaining healthy skin, which serves as a protective barrier for the body. When the body is deprived of crucial vitamins, minerals, or protein, this vital organ often displays symptoms first. The appearance of a rash can be one of the most visible indicators that something is wrong, with the specific features of the rash often providing clues to the underlying nutritional deficiency.

Kwashiorkor: The 'Flaky Paint' Rash

One of the most well-known types of malnutrition-related rashes is associated with kwashiorkor, a severe protein-energy malnutrition disorder. Kwashiorkor results from insufficient protein intake despite adequate caloric intake and is most often seen in children in developing countries. The rash has several characteristic features:

Appearance: Initially presents as hypopigmented (lighter) or erythematous (red) patches. These patches progress into thick, hyperkeratotic (thickened) and hyperpigmented (darkened) plaques, especially in areas of pressure like the buttocks, groin, and behind the knees.
Texture: The fragile skin peels away in large sheets, revealing the underlying lighter skin. This distinctive presentation is often described as 'flaky paint dermatosis' or 'peeling paint'.
Affected areas: The rash is most common on areas subject to friction, such as the buttocks, groin, elbows, and knees.
Associated signs: Kwashiorkor is also accompanied by other symptoms, including generalized edema (swelling), a distended abdomen, and thinning, brittle, or reddish-colored hair.

Pellagra: The Photosensitive Dermatitis

Pellagra is a systemic disease caused by a deficiency of niacin (vitamin B3). The dermatitis associated with pellagra is highly distinctive and primarily affects sun-exposed areas of the body.

Appearance: The rash starts with a red, sunburn-like appearance. Over time, it progresses to become rough, scaly, and deeply pigmented.
Symmetry and Distribution: The rash is typically symmetrical and has a sharp demarcation at the edge of clothing. Common areas include the face, neck, arms, and feet.
Casal's Necklace: A hallmark sign is a dark, hyperpigmented band or collar around the neck, known as Casal's collar or necklace.
Glove and Boot: Sharply defined plaques resembling gloves or boots can appear on the hands and feet.

Acrodermatitis Enteropathica: The Periorificial and Acral Rash

Caused by zinc deficiency, acrodermatitis enteropathica (AE) is an inherited or acquired condition that results in a distinct rash, often accompanied by diarrhea and alopecia.

Appearance: The dermatitis begins as sharply demarcated erythematous and eczematous plaques that can become vesicular (blister-like) or pustular. The affected skin may look glazed, cracked, and fissured.
Distribution: The rash characteristically appears around the body's orifices (periorificial), such as the mouth, nose, eyes, and anus. It also affects the hands and feet (acral areas).
Specific Features: The perioral rash often has a U-shaped distribution that spares the upper lip.
Progression: The plaques can be crusted and scaly, and secondary infection is common due to immune dysregulation.

Scurvy: The Hemorrhagic and Follicular Rash

Scurvy results from a severe deficiency of vitamin C, which is essential for collagen synthesis. This deficiency weakens blood vessels, leading to characteristic skin findings.

Appearance: A scurvy rash manifests as small, red or blue spots under the skin, caused by tiny hemorrhages around hair follicles (perifollicular hemorrhage).
Bumps: Rough, bumpy skin (keratosis pilaris) can also develop on the back of the upper arms and thighs due to a buildup of keratin in the hair follicles.
Hair: Corkscrew hairs, where body hair is coiled and broken, are another defining sign.
Bruising: Easy and extensive bruising is also common due to weakened blood vessels.

Comparison of Malnutrition-Related Rashes


Type of Malnutrition	Key Nutrient Deficiency	Rash Appearance	Location	Additional Features
Kwashiorkor	Protein	'Flaky paint' dermatosis; peeling, hyperpigmented plaques	Buttocks, groin, pressure areas	Edema, distended abdomen, brittle hair
Pellagra	Niacin (Vitamin B3)	Symmetrical, hyperpigmented, scaly rash; looks like sunburn	Sun-exposed areas (face, neck, hands)	Casal's necklace, dementia, diarrhea
Acrodermatitis Enteropathica	Zinc	Sharply demarcated erythematous, eczematous, or blistering plaques	Periorificial (around mouth, eyes, anus), acral (hands, feet)	Alopecia, diarrhea, irritability
Scurvy	Vitamin C	Perifollicular hemorrhage (red spots), bumpy skin	Legs, thighs, upper arms	Easy bruising, coiled hair, joint pain
B-Complex Deficiencies	Vitamin B2 (Riboflavin), B6 (Pyridoxine)	Seborrheic dermatitis-like rash; scaly and greasy	Face (nasolabial folds), scalp, perineum	Angular stomatitis (cracked mouth corners), glossitis

Management and Diagnosis

If a malnutrition rash is suspected, a medical evaluation is crucial. Healthcare providers will perform a physical exam and may order blood tests, such as a complete blood count or serum zinc levels, to confirm the diagnosis. Treatment involves addressing the underlying nutritional deficiency, which may include oral supplements and dietary modifications. In cases of severe malnutrition, hospitalized patients may receive total parenteral nutrition. Addressing the nutritional imbalance typically leads to a resolution of the skin issues over time.

Conclusion

A malnutrition rash is a visible and serious indicator of an underlying nutritional deficiency. Unlike common skin conditions, these rashes often present with unique features related to the specific missing nutrient, such as protein, zinc, or niacin. From the peeling 'flaky paint' of kwashiorkor to the symmetrical, photosensitive rash of pellagra, recognizing these distinct dermatological signs is crucial for early intervention. Proper diagnosis and repletion of the deficient nutrients are key to treating the rash and improving overall health. It is essential to consult a healthcare professional for a correct diagnosis and treatment plan if you suspect a malnutrition-related rash.

How a Registered Dietitian Can Help

A registered dietitian nutritionist (RDN) plays a key role in managing and preventing malnutrition-related skin conditions. They can assess your current dietary intake, identify specific nutritional gaps, and develop a personalized plan to correct deficiencies. This may include recommending foods rich in the necessary nutrients or advising on appropriate supplementation. An RDN can also provide education on healthy eating habits to prevent future occurrences and promote long-term skin health.

Authoritative Resource

For more information on dermatological conditions, including those caused by nutritional deficiencies, a comprehensive resource is DermNet, a trusted online dermatology reference.

Frequently Asked Questions

A flaky rash is typically associated with kwashiorkor, a severe form of protein-energy malnutrition. The rash, known as 'flaky paint dermatosis,' features peeling, hyperpigmented plaques over pressure areas.

Yes, deficiencies in several vitamins, including niacin (B3), vitamin C, and some B-complex vitamins, can cause specific types of rashes. Pellagra (niacin deficiency) and scurvy (vitamin C deficiency) are two examples where a rash is a prominent symptom.

Yes, zinc deficiency can cause a characteristic rash around the mouth and other orifices. This condition, called acrodermatitis enteropathica, results in erythematous and eczematous plaques with a U-shaped distribution around the lips.

Casal's necklace is a dark, hyperpigmented, and scaly collar-like rash around the neck. It is a classic sign of pellagra, which is caused by a deficiency of niacin (vitamin B3).

Treatment for a malnutrition-related rash involves correcting the underlying nutritional deficiency. This is typically done through oral supplements and a nutrient-rich diet, with severe cases sometimes requiring more intensive re-alimentation.

A vitamin C deficiency rash (scurvy) appears as tiny red or blue spots caused by perifollicular hemorrhages (bleeding around hair follicles). It can also manifest as rough, bumpy 'chicken skin' on the limbs.

Yes, a lack of protein can lead to skin problems. In severe cases, it causes the 'flaky paint' dermatosis of kwashiorkor. Milder deficiencies can also result in issues like dry skin and impaired wound healing.