Rickets and Osteomalacia: What Disease is Caused by the Inadequacy of Vitamin D?

December 7, 2025 •

3 min read

An inadequacy of vitamin D can have profound effects on bone health, but many wonder: what disease is caused by the inadequacy of vitamin D? This deficiency notably leads to the bone-softening disorders of rickets in children and osteomalacia in adults, causing pain and weakness. Millions are affected worldwide, making this a critical public health concern.

Quick Summary

Rickets in children and osteomalacia in adults are the primary diseases resulting from a lack of vitamin D, leading to softened bones, muscle weakness, and pain.

Key Points

Rickets in Children: An inadequacy of vitamin D causes rickets, a condition leading to weak, soft, and malformed bones in growing children.
Osteomalacia in Adults: The adult counterpart to rickets, osteomalacia, results in the painful softening of existing bones due to chronic vitamin D deficiency.
Key Role of Vitamin D: This vitamin is essential for the body to absorb calcium and phosphorus, crucial minerals for building and maintaining strong bones.
Diagnosis is Key: Blood tests measuring 25-hydroxyvitamin D levels are the standard method for diagnosing vitamin D inadequacy.
Prevention is Possible: Ensuring adequate sunlight exposure, eating fortified foods, and taking supplements can prevent vitamin D deficiency.
Treatment Options: Treatment typically involves high-dose vitamin D supplementation to restore normal levels, along with calcium if needed.

Rickets: Bone Disease in Children

Rickets affects children with growing bones, causing them to become soft and weak due to poor mineralization. While less common in developed countries now due to fortified foods, it remains a concern for some populations.

Symptoms of Rickets

Rickets symptoms vary and may include:

Bowed or bent legs.
Delayed growth.
Bone pain.
Muscle weakness.
Skeletal deformities.
Dental problems.
Wider joints at wrists and ankles.
Severe cases may cause muscle spasms and seizures.

Key Risk Factors for Rickets

Factors increasing a child's risk include:

Insufficient sun exposure.
Darker skin.
Exclusive breastfeeding without supplementation.
Vegetarian/vegan diets without fortification.
Certain medical conditions affecting absorption.

Osteomalacia: Adult Bone Softening

In adults, vitamin D inadequacy causes osteomalacia, where mature bones soften. This leads to weak bones prone to fractures.

Symptoms of Osteomalacia

Adult symptoms often include:

Bone pain.
Muscle weakness.
Increased fracture risk.
Waddling gait.
Fatigue.

Key Causes and Risk Factors in Adults

Risks for adults are similar to children and general vitamin D deficiency, including:

Insufficient sun exposure.
Aging.
Malabsorption syndromes.
Chronic kidney or liver disease.
Certain medications.

Comparing Rickets and Osteomalacia

Both are caused by vitamin D inadequacy but differ based on age:


Feature	Rickets	Osteomalacia
Affected Population	Children with open growth plates.	Adults with closed growth plates.
Primary Pathology	Impaired mineralization at growth plates.	Poor mineralization of mature bone matrix.
Skeletal Effects	Deformities like bowed legs.	Pain, weakness, fracture risk.
Other Symptoms	Dental defects, possible seizures.	Increased fracture susceptibility.

Diagnosis and Treatment

Early diagnosis and treatment are vital.

How is it Diagnosed?

Diagnosis involves physical exams, risk assessment, and tests. A blood test for 25-hydroxyvitamin D is key. X-rays may be used, especially for rickets.

Treatment Options

Treatment aims to restore vitamin D levels and includes:

High-dose supplements.
Calcium supplements if needed.
Moderate sun exposure.
Dietary changes with vitamin D-rich or fortified foods.
Treating underlying conditions.

Preventing Vitamin D Inadequacy

Prevention is crucial. A balanced approach includes diet, sun, and supplements.

Prevention Strategies

Sunlight: Regular, moderate exposure is beneficial.
Dietary Sources: Include fatty fish, egg yolks, and liver.
Fortified Foods: Consume fortified milk, cereals, etc..
Supplementation: Consider supplements, especially for high-risk groups. Consult a doctor for dosage.
For Infants: Supplement breastfed infants as recommended.

Conclusion: The Importance of Addressing Vitamin D Inadequacy

In summary, vitamin D inadequacy causes rickets in children and osteomalacia in adults. These conditions highlight the vitamin's importance for bone health at all ages. Prevention through diet, sun, and supplements is key. Early treatment can reverse symptoms. For more details on vitamin D, consult resources like the NCBI Bookshelf. Awareness and action are vital for skeletal health.

Key Factors Contributing to Vitamin D Inadequacy

Inadequate Sunlight: Leading cause due to less production from UV exposure.
Malabsorption: Disorders like celiac and Crohn's hinder absorption.
Age-Related Decline: Older skin is less efficient at production.
Melanin Interference: Darker skin reduces production.
Dietary Gaps: Lack of vitamin D-rich or fortified foods.
Chronic Illnesses: Kidney and liver diseases affect activation.

Conclusion

Understanding the diseases caused by vitamin D inadequacy, rickets and osteomalacia, is vital. They are preventable and treatable, but can have lasting impacts if ignored. Maintaining adequate vitamin D through sun, diet, and supplementation supports skeletal health across the lifespan. Informed prevention reduces these disorders, improving individual and community well-being. Continuous awareness and access to healthcare for testing and treatment are essential.

What to Know About Vitamin D Deficiency

Primary Diseases: Rickets (children) and osteomalacia (adults) cause soft, weak bones.
Bone Health: Vitamin D aids calcium and phosphorus absorption for bone mineralization.
Risk Groups: Infants, elderly, dark-skinned individuals, and those with certain conditions are at higher risk.
Diagnosis: A blood test for 25-hydroxyvitamin D is standard.
Prevention: Strategies include sun exposure, fortified foods, natural sources, and supplements.
Treatment: High-dose supplements and addressing underlying causes.
Long-Term Effects: Untreated deficiency can cause permanent bone damage and weakness.

Frequently Asked Questions

The most common cause of vitamin D deficiency is inadequate exposure to sunlight, as the body produces the vitamin in response to UV radiation.

Early signs of rickets in infants can include muscle spasms (tetany) and a soft skull.

Osteomalacia is the softening of bones due to poor mineralization, while osteoporosis is a condition where bones become porous and brittle due to loss of bone density.

Yes, a diet lacking in vitamin D-rich or fortified foods, combined with minimal sun exposure, is a significant risk factor for inadequacy.

Those at higher risk include the elderly, people with dark skin, individuals with limited sun exposure, and those with malabsorption disorders.

Yes, excessive intake of vitamin D from supplements can lead to toxicity, though it is rare. It is not possible to get too much from sun exposure.

Vitamin D deficiency is diagnosed through blood tests that measure the level of 25-hydroxyvitamin D in the body.

Yes, rickets can often be cured with vitamin D and calcium supplementation, especially if caught and treated early. Severe cases, if untreated, can cause permanent damage.