What are the examples of dietary deficiency diseases?

January 8, 2026 •

5 min read

According to the World Health Organization (WHO), micronutrient deficiencies affect more than two billion people worldwide. These are among the most common examples of dietary deficiency diseases, which are health conditions caused by a lack of essential vitamins, minerals, and other nutrients in the diet. Understanding these conditions is the first step toward effective prevention and treatment.

Quick Summary

This article provides key examples of dietary deficiency diseases, detailing the causes, symptoms, and preventative measures for each. It covers deficiencies of essential vitamins, minerals, and protein, highlighting how proper nutrition is vital for overall health.

Key Points

Scurvy: Caused by severe Vitamin C deficiency, leading to fatigue, bleeding gums, and poor wound healing due to impaired collagen formation.
Rickets: A Vitamin D deficiency in children causes softened bones, often resulting in bowed legs and other skeletal deformities.
Iron-Deficiency Anemia: A lack of iron, the most common deficiency worldwide, causes a shortage of healthy red blood cells, leading to fatigue and weakness.
Kwashiorkor and Marasmus: These are severe forms of protein-energy malnutrition (PEM), with Kwashiorkor resulting from a protein lack (causing swelling) and Marasmus from a calorie lack (causing wasting).
Pellagra: This disease is due to a niacin (B3) deficiency and is characterized by the "4 Ds": dermatitis, diarrhea, dementia, and death.
Goiter: An enlarged thyroid gland caused by insufficient iodine intake, which affects the production of essential thyroid hormones.
Beriberi: A thiamin (Vitamin B1) deficiency, leading to either wet (cardiovascular) or dry (nervous system) symptoms.

The Broad Spectrum of Nutritional Deficiencies

Dietary deficiency diseases arise when the body does not receive a sufficient quantity of vital nutrients necessary for proper function, growth, and repair. While a lack of specific nutrients is a primary cause, other factors can impair absorption, such as medical conditions like Crohn's disease or certain surgeries. These diseases can manifest with a wide range of symptoms, from mild fatigue to severe organ damage and even death if left untreated.

Vitamin Deficiency Diseases

Scurvy (Vitamin C Deficiency)

Scurvy is caused by a severe, prolonged lack of vitamin C (ascorbic acid), which is crucial for collagen synthesis, the body's main structural protein. Without vitamin C, connective tissues weaken, leading to classic symptoms.

Symptoms: Bleeding and swollen gums, loose teeth, small red or blue skin hemorrhages (petechiae), joint pain, fatigue, and poor wound healing.
Causes: A diet severely lacking in fresh fruits and vegetables. Historical cases were common among sailors on long voyages with no access to fresh produce.

Rickets (Vitamin D Deficiency)

Rickets is a condition affecting children, causing their bones to soften and weaken due to a lack of vitamin D, calcium, or both. Vitamin D is essential for the body to absorb calcium and phosphorus.

Symptoms: Bowed legs, bone pain, stunted growth, muscle weakness, and skeletal deformities.
Causes: Insufficient sunlight exposure (which helps the skin produce vitamin D) and inadequate intake of vitamin D-rich foods.

Pellagra (Vitamin B3 / Niacin Deficiency)

Pellagra is a systemic disease caused by a severe deficiency of niacin (vitamin B3) or its precursor, the amino acid tryptophan. It is classically associated with diets heavily reliant on untreated corn.

Symptoms: Often called the “4 Ds” of pellagra: Dermatitis (a sun-sensitive rash), Diarrhea, Dementia, and eventually Death.
Causes: A monotonous diet of untreated corn, which contains niacin in a form that is not easily absorbed by the body.

Beriberi (Thiamin / Vitamin B1 Deficiency)

Beriberi occurs from a thiamin deficiency and primarily affects the nervous and cardiovascular systems.

Symptoms: It manifests as either "wet" beriberi, which affects the heart and causes swelling, or "dry" beriberi, which causes nerve damage and muscle paralysis.
Causes: Common in populations subsisting on processed white rice, which is stripped of its thiamin content. Alcohol misuse can also interfere with thiamin absorption.

Mineral Deficiency Diseases

Iron-Deficiency Anemia

As the most common nutritional deficiency globally, iron deficiency leads to a reduced production of healthy red blood cells.

Symptoms: Fatigue, weakness, pale skin, shortness of breath, dizziness, and a rapid heartbeat.
Causes: Inadequate dietary iron intake, blood loss from menstruation or internal bleeding, and poor iron absorption.

Goiter (Iodine Deficiency)

Iodine deficiency causes the thyroid gland to enlarge, resulting in a condition called goiter. Iodine is vital for producing thyroid hormones, which regulate growth and metabolism.

Symptoms: Swelling in the neck, fatigue, and weight gain. Severe deficiency during pregnancy can cause cretinism (severe developmental and intellectual disability) in infants.
Causes: Insufficient iodine intake, often due to living in regions where soil is low in iodine, such as inland, mountainous areas.

Osteoporosis (Calcium and Vitamin D Deficiency)

While distinct, a lack of calcium and vitamin D can lead to osteoporosis in adults, where bones become porous and brittle.

Symptoms: Increased risk of fractures, loss of height, and a stooped posture.
Causes: Long-term insufficient calcium intake, poor vitamin D status affecting calcium absorption, and hormonal changes associated with aging.

Protein-Energy Malnutrition (PEM)

PEM is a spectrum of severe malnutrition disorders caused by a lack of protein and/or energy (calories). The two most severe forms are kwashiorkor and marasmus.

Kwashiorkor: Characterized by a severe protein deficiency, often with enough calorie intake, leading to edema (swelling) of the limbs, feet, and face.
Marasmus: Involves a severe deficiency of both protein and calories, resulting in significant muscle and fat wasting and an emaciated appearance.

Comparison of Key Deficiency Diseases


Feature	Scurvy	Rickets	Iron-Deficiency Anemia	Pellagra
Key Nutrient	Vitamin C	Vitamin D, Calcium	Iron	Niacin (B3), Tryptophan
Primary Effect	Weakens connective tissue	Softens and weakens bones	Decreased red blood cell production	Systemic cellular energy failure
Key Symptoms	Bleeding gums, petechiae, fatigue	Bowed legs, bone pain, growth delays	Fatigue, pale skin, weakness	Dermatitis, diarrhea, dementia
Vulnerable Group	Infants, older adults, poor diet	Children, limited sun exposure	Women of childbearing age, children	Populations with untreated corn as staple
Prevention	Citrus fruits, fresh produce	Sunlight exposure, fortified milk, supplements	Iron-rich foods, Vitamin C sources	Balanced diet, fortified grains

Preventing and Managing Dietary Deficiencies

Prevention is the most effective approach to combating dietary deficiency diseases. A balanced diet rich in a variety of foods is the cornerstone of good health.

Strategies for prevention

Dietary Diversification: Incorporate a wide range of fruits, vegetables, whole grains, lean proteins, and dairy to ensure a broad spectrum of nutrients.
Fortified Foods: Many countries fortify staple foods like salt (with iodine), milk (with vitamin D), and cereals (with iron and B vitamins), which significantly reduces deficiency risks.
Supplements: When dietary intake is insufficient, supplements can help meet nutritional needs. This is particularly important for at-risk groups like pregnant women, the elderly, or those on restrictive diets.
Sunlight Exposure: Moderate, safe sun exposure helps the body produce vitamin D naturally. However, individuals with darker skin or who live in northern latitudes may require more exposure or supplementation.
Education and Monitoring: Understanding nutritional needs and undergoing regular health check-ups can detect early signs of a deficiency before it becomes severe. You can learn more from the World Health Organization (WHO) website about efforts to combat these issues globally: https://www.who.int/data/nutrition/nlis/info/vitamin-a-deficiency.

Conclusion

Dietary deficiency diseases, while largely preventable, continue to affect a significant portion of the global population. From well-known historical conditions like scurvy and rickets to prevalent issues like iron-deficiency anemia and protein-energy malnutrition, the impact on human health can be profound. By prioritizing a diverse and nutrient-rich diet, utilizing fortified foods, and seeking medical guidance when necessary, most people can effectively protect themselves and their families from these preventable illnesses. Addressing the root causes, from food scarcity to poor dietary habits, remains key to improving public health outcomes worldwide.

Frequently Asked Questions

The primary cause is an insufficient intake of essential nutrients like vitamins, minerals, and proteins through diet. Other contributing factors can include malabsorption issues due to medical conditions, or increased nutrient needs during certain life stages.

Yes, in most cases, dietary deficiency diseases can be effectively treated and cured by restoring the missing nutrients, either through dietary changes, supplementation, or fortified foods. However, severe, long-term deficiencies may cause irreversible damage, such as blindness from vitamin A deficiency or neurological damage from B12 deficiency.

Early signs of vitamin D deficiency in children can include bone pain, muscle weakness, and delayed growth. In adults, a deficiency can contribute to osteomalacia, leading to bone pain and muscle weakness.

As vitamin B12 is primarily found in animal products, vegans are at a higher risk of deficiency. Prevention involves consuming B12-fortified foods (like cereals, plant milks) or taking regular vitamin B12 supplements, as advised by a healthcare provider.

Scurvy is rare in developed countries but still occurs in populations with inadequate nutrition, such as those with substance abuse problems, strict restrictive diets, or in developing countries. Public health efforts and food fortification have made it largely a historical disease in many places.

Kwashiorkor is mainly a protein deficiency, characterized by edema (swelling), particularly in the abdomen, even when calorie intake is moderate. Marasmus is a severe deficiency of both protein and calories, resulting in an overall wasting of body fat and muscle, leading to a visibly emaciated appearance.

Food fortification involves adding essential vitamins and minerals to commonly consumed foods, such as iodine to salt or vitamin D to milk. This cost-effective strategy significantly reduces the risk of deficiency diseases on a large scale by ensuring that staple foods provide key nutrients.