What is rickets, and how does it differ from osteomalacia?
Rickets is a disorder of bone mineralization in growing children—it affects the cartilage of the epiphyseal plates and causes irreversible bone deformities if left untreated. Osteomalacia is its counterpart in adults, after the epiphyseal plates have closed. Both are most often caused by a severe vitamin D3 deficiency. Our vitamin D product line offers formulas tailored to each age group.
- Rickets (children): affects active epiphyseal plates—long bones unable to mineralize properly—characteristic deformities: bowlegs (genu varum), funnel chest, rib spurs, craniotabes (soft skull)
- Osteomalacia (adults): generalized bone softening—diffuse bone pain + muscle weakness + spontaneous fractures (Looser’s pseudofractures)—may mimic fibromyalgia or chronic low back pain
- Both are diagnosed through laboratory tests (low 25-OH vitamin D + elevated alkaline phosphatase + low calcium) and radiological imaging
- Genetic rickets (mutations in 1α-hydroxylase or the vitamin D receptor) is rare but requires a different, specialized treatment
Which populations are at risk for vitamin D deficiency and rickets?
Targeted prevention among at-risk populations is the most effective strategy—appropriate supplementation prevents permanent complications.
- Breastfed infants: Breast milk is low in vitamin D—routine supplementation is recommended by the HAS starting at birth: 1,000–1,200 IU/day until 18 months of age, regardless of feeding method
- Children with dark skin: Melanin acts as a natural filter for vitamin D synthesis in the skin—higher risk in France, especially in regions with little sunlight
- Children with limited sun exposure: prolonged time spent indoors, covering clothing, northern regions—insufficient skin synthesis in France from October through March, even during the day
- Pregnant women with deficiency: maternal deficiency = neonatal deficiency—D3 supplementation in late pregnancy (single-dose streptokinase or daily D3)
- Elderly adults in care facilities: virtually no sun exposure + reduced ability to synthesize vitamin D in the skin with age — routine vitamin D3 supplementation recommended
How to diagnose and treat rickets?
Laboratory diagnosis is essential before any intensive treatment—a deficiency must be documented and quantified to determine the appropriate dose.
- Laboratory workup: serum 25-OH vitamin D (severe deficiency < 12 ng/mL, insufficiency 12–30 ng/mL), serum calcium, serum phosphorus, alkaline phosphatase (ALP)—elevated PTH in cases of prolonged deficiency
- X-rays: widening and irregularity of the metaphyses (growth plates), “ground-glass” appearance of the growth plates, axial deformities of the limbs
- Curative treatment: Vitamin D3 loading doses (stoss therapy: 100,000–200,000 IU as a single dose or in divided doses) followed by maintenance therapy — resolution of laboratory abnormalities within 2–4 weeks, radiographic abnormalities within 2–3 months
- Concomitant correction of calcium levels: 500–1,000 mg of calcium per day—without sufficient calcium, normalization of vitamin D3 levels may trigger “calcium starvation” (paradoxical hypocalcemia)
- Severe deformities: orthopedic follow-up — often spontaneous correction with early treatment — corrective osteotomy in persistent cases after growth has ceased
How can rickets be prevented in daily life?
- Routine supplementation for infants: 1,000–1,200 IU/day of vitamin D3 from birth to 18 months — regardless of feeding method — see our vitamin D product line
- Moderate sun exposure: 15–20 min/day on the forearms and face between 11 a.m. and 3 p.m. — impossible to achieve in France from October through March — never sufficient on its own for infants and young children
- Vitamin D-rich foods: fatty fish (salmon, mackerel, sardines), eggs, fortified dairy products — dietary intake is generally insufficient to meet a child’s needs without supplementation
- Magnesium: a cofactor in the renal activation of vitamin D—a magnesium deficiency can render D3 supplementation ineffective
- Annual serum testing is recommended for at-risk children (dark skin, limited sun exposure, malabsorption) to adjust supplementation
