Understanding the Nutritional Link: Which Vitamin Deficiency Leads to Rickets?

October 26, 2025 •

3 min read

According to the National Health and Nutrition Examination Survey (NHANES) 2011-2012, vitamin D deficiency is becoming increasingly common, even in groups not traditionally labeled “at-risk”. The softening and weakening of bones known as rickets is most often caused by a prolonged deficiency of vitamin D.

Quick Summary

The most common cause of rickets is a severe lack of vitamin D, which is essential for absorbing calcium and phosphorus for bone mineralization. The condition, which primarily affects children, can also be exacerbated by insufficient calcium intake.

Key Points

Primary Cause: Rickets is most commonly a result of an extreme and prolonged vitamin D deficiency.
Role of Vitamin D: Vitamin D is essential for the body to properly absorb calcium and phosphorus, the minerals needed for strong bones.
Key Risk Factors: At-risk groups include exclusively breastfed infants, people with darker skin, and those with limited sun exposure.
Common Symptoms: Signs include bone pain, weakened muscles, delayed growth, and skeletal deformities like bowed legs.
Prevention and Treatment: Prevention involves adequate vitamin D from sun, diet, and supplements. Treatment typically includes high-dose vitamin D and calcium.

The Primary Cause: Vitamin D and Its Critical Role

Rickets, a condition causing weak and softened bones, is most commonly the result of an extreme and prolonged vitamin D deficiency. This happens because vitamin D is a crucial player in the body's ability to absorb and utilize calcium and phosphorus, the minerals that make up strong, hard bone tissue. When vitamin D levels are insufficient, the body cannot absorb enough calcium and phosphorus from food, leading to poor bone mineralization. In response, the body may release hormones that draw these minerals from the bones themselves, further weakening them.

How Vitamin D Works in the Body

Vitamin D is a unique nutrient the body can synthesize through sunlight exposure. It is converted to its active form in the liver and kidneys to aid in calcium and phosphorus absorption. Vitamin D is also obtained from certain foods.

Signs and Symptoms of Rickets

Rickets manifests with several distinct physical signs, most of which are related to bone weakness and are especially evident in growing children. Symptoms include skeletal deformities (bowed legs, knock-knees, etc.), bone pain, enlarged joints, delayed development, muscle weakness, dental problems, and in severe cases, muscle cramps and seizures.

Who is at Risk?

Risk factors for rickets include exclusive breastfeeding, dark skin pigmentation, limited sun exposure, being an infant of a mother with severe vitamin D deficiency, certain gastrointestinal conditions, and obesity.

Prevention and Dietary Management

Preventing rickets involves ensuring adequate vitamin D and calcium intake through sunlight, diet, and supplements. Strategies include daily vitamin D supplements for all breastfed infants and others at risk, sensible sun exposure, and consuming fortified foods. While sun exposure is a primary source, foods like fatty fish, cod liver oil, egg yolks, beef liver, and fortified products also contribute.

Comparison of Rickets Types

Nutritional rickets is the most common form, but other types exist with different causes and treatments.


Feature	Nutritional Rickets (Vitamin D Deficiency)	Hereditary Rickets (e.g., Hypophosphatemic)
Cause	Lack of sufficient vitamin D (and/or calcium) in the diet and/or from sun exposure.	Genetic defect leading to kidney problems with phosphate handling or impaired vitamin D metabolism.
Key Issue	Body cannot absorb minerals for bone mineralization due to low vitamin D.	Primarily an inability of renal tubules to reabsorb phosphate.
Onset	Typically appears in infants and young children during periods of rapid growth.	Often presents during the toddler years (1-2 years) or later.
Treatment	High-dose vitamin D and calcium supplementation.	Requires specialized treatment, often including phosphate supplements and active vitamin D (calcitriol).
Prognosis	Usually resolves completely with proper medical treatment and management.	Requires ongoing, specialized care and monitoring.

Diagnosis and Treatment

Diagnosing rickets involves a physical exam, blood tests for vitamin D and mineral levels, and X-rays. Treatment for vitamin D deficiency-related rickets includes high-dose supplements and increased calcium. Symptoms like pain improve quickly, while deformities may require more time and potentially intervention. Consulting a specialist is important for treatment.

Conclusion

Rickets in children is a bone mineralization defect most often caused by a vitamin D deficiency, which impairs calcium and phosphorus absorption essential for strong bones. Risk factors include inadequate sun, dark skin, exclusive breastfeeding, and certain medical conditions. Nutritional rickets is preventable and treatable with proper diet, sun exposure, and vitamin D and calcium supplements, especially for those at risk. These strategies are key to protecting children's skeletal health. For more on nutrition, {Link: Harvard T.H. Chan School of Public Health https://nutritionsource.hsph.harvard.edu/vitamin-d/} is a good resource.

Frequently Asked Questions

A vitamin D deficiency leads to rickets because vitamin D is necessary for the body to absorb calcium and phosphorus from the intestines. Without enough vitamin D, these essential minerals cannot be properly absorbed, resulting in poor bone mineralization and softening.

Yes, the equivalent condition to rickets in adults is called osteomalacia. It also results from vitamin D deficiency, causing weakened and softened bones, but without the skeletal deformities typically seen in growing children.

Some early signs of rickets include bone pain or tenderness, widened joints in the wrists and ankles, and muscle weakness. In infants, a softened skull (craniotabes) can also be an early indicator.

Sun exposure is a natural way for the body to produce vitamin D, but it's not always sufficient. Factors like latitude, season, skin pigmentation, and sunscreen use can limit production. Many people, especially those at higher latitudes or with darker skin, need dietary or supplemental vitamin D.

Few foods naturally contain high amounts of vitamin D. Good dietary sources include fatty fish (salmon, mackerel), fish oil, egg yolks, beef liver, and fortified foods such as milk, cereal, and orange juice.

Yes, rickets can also be caused by a severe deficiency of calcium, particularly in children with low dietary intake. However, low vitamin D is the most common cause of the nutritional form of the disease.

Nutritional rickets is primarily treated with supplements of vitamin D and calcium, often in high doses initially. In severe cases, particularly if significant deformities have developed, options like bracing or surgery may be necessary.

Yes, nutritional rickets is highly preventable. Ensuring adequate intake of vitamin D and calcium through diet, supplementation, and safe sun exposure is the key to preventing the condition, especially in high-risk populations like breastfed infants.