Rickets in Babies (Vitamin D Bone Disease)
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published AAP, NIH, AAP guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect rickets in babies (vitamin d bone disease), here is what the evidence says.
The short answer
Rickets is a condition in which bones become soft and weak due to severe deficiency of vitamin D, calcium, or phosphorus. Signs include bowed legs, widened wrists and ankles, delayed closure of the fontanelle, and poor growth. Exclusively breastfed babies with darker skin tones and limited sun exposure are at highest risk. Rickets is preventable with vitamin D supplementation (the AAP recommends 400 IU daily for all breastfed infants) and is treatable when caught early.
Key takeaways
- Rickets is a condition in which bones become soft and weak due to severe deficiency of vitamin D, calcium, or phosphorus. Signs include bowed legs, widened wrists and ankles, delayed closure of the fontanelle, and poor growth. Exclusively breastfed babies with darker skin tones and limited sun exposure are at highest risk. Rickets is preventable with vitamin D supplementation (the AAP recommends 400 IU daily for all breastfed infants) and is treatable when caught early.
- Usually normal when: Your baby is receiving the recommended 400 IU of vitamin D daily (via drops or adequate formula intake) and is growing well along their growth curve
- Call your doctor if: Your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP, NIH guidelines, rickets is a condition in which bones become soft and weak due to severe deficiency of vitamin D, calcium, or phosphorus. Signs include bowed legs, widened wrists and ankles, delayed closure of the fontanelle, and poor growth. Exclusively breastfed babies with darker skin tones and limited sun exposure are at highest risk. Rickets is preventable with vitamin D supplementation (the AAP recommends 400 IU daily for all breastfed infants) and is treatable when caught early. At 0-3 months, signs of rickets are uncommon this early but can occur in babies born to mothers with severe vitamin D deficiency. Very early signs include craniotabes (a softening of the skull bones that feels like pressing on a ping-pong ball), irritability, and poor feeding. The AAP recommends all breastfed and partially breastfed infants receive 400 IU of vitamin D drops daily starting within the first few days of life. Formula-fed babies typically get adequate vitamin D if consuming at least 32 ounces of fortified formula per day. It is generally considered normal when your baby is receiving the recommended 400 IU of vitamin D daily (via drops or adequate formula intake) and is growing well along their growth curve. However, you should contact your pediatrician promptly if your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care.
Normal vs. Concerning
By Age
What to expect by age
0-3 months
Signs of rickets are uncommon this early but can occur in babies born to mothers with severe vitamin D deficiency. Very early signs include craniotabes (a softening of the skull bones that feels like pressing on a ping-pong ball), irritability, and poor feeding. The AAP recommends all breastfed and partially breastfed infants receive 400 IU of vitamin D drops daily starting within the first few days of life. Formula-fed babies typically get adequate vitamin D if consuming at least 32 ounces of fortified formula per day.
3-12 months
This is when rickets may become more clinically apparent, particularly in exclusively breastfed babies who have not received vitamin D supplementation and who have darker skin pigmentation or limited sun exposure. You may notice the fontanelle (soft spot) seems larger than expected, the wrists appear widened at the bone-cartilage junction, or the ribcage has noticeable bumps along the front (called a rachitic rosary). Delayed motor milestones such as difficulty sitting or pulling to stand may occur because weakened bones and muscles impair movement.
1-3 years
Toddlers with rickets may develop progressively bowed legs as they begin bearing weight, because softened bones bend under the body's load. Other signs include a waddling gait, delayed walking, bone pain or tenderness, dental problems (delayed eruption, enamel defects), and poor linear growth. Diagnosis is confirmed with blood tests showing low vitamin D, low calcium or phosphorus, elevated alkaline phosphatase, and elevated parathyroid hormone, along with X-rays of the wrists or knees showing characteristic widening and fraying of the growth plates.
3-5 years
Rickets in older children can occur with severely restrictive diets, malabsorption conditions such as celiac disease or inflammatory bowel disease, chronic kidney disease, or certain rare genetic forms of rickets (hypophosphatemic rickets). Signs include persistent bone pain, muscle weakness, fatigue, poor growth, and skeletal deformities. Treatment involves high-dose vitamin D and calcium supplementation under medical supervision. Severe bowing that does not improve with medical treatment may eventually require surgical correction.
What to Tell Your Pediatrician
- Describe when you first noticed rickets in babies (vitamin d bone disease) and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your breastfed baby has not been receiving vitamin D supplementation and you notice widened wrists, prominent rib bumps, or worsening bowed legs.
- Mention if your baby's fontanelle seems unusually large or has not shown any signs of closing by 18 months.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Your baby is receiving the recommended 400 IU of vitamin D daily (via drops or adequate formula intake) and is growing well along their growth curve
- Your breastfed baby has slightly bowed legs but is receiving vitamin D supplementation and the bowing is consistent with normal physiologic bowing that improves by age 2-3
- Your baby's fontanelle is still open at 12-18 months, which is within the normal range (fontanelles typically close between 9-24 months)
- Your toddler has mildly bowed legs that are symmetrical and gradually improving with age and adequate nutrition
- Your breastfed baby has not been receiving vitamin D supplementation and you notice widened wrists, prominent rib bumps, or worsening bowed legs
- Your baby's fontanelle seems unusually large or has not shown any signs of closing by 18 months
- Your toddler has bowed legs that are getting worse rather than improving, especially with a restricted diet or limited sun exposure
- Your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care
- Your child sustains a fracture from a minor fall or normal activity, suggesting significantly weakened bones that need urgent evaluation
What You Can Do at Home
- Keep track of when you notice rickets in babies (vitamin d bone disease) — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your baby is receiving the recommended 400 IU of vitamin D daily (via drops or adequate formula intake) and is growing well along their growth curve — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care.
Related Conditions
Vitamin D Deficiency in Babies
Vitamin D is essential for calcium absorption and healthy bone development. Breast milk alone does not provide adequate vitamin D, so the AAP recommends all breastfed and partially breastfed infants receive 400 IU of vitamin D daily beginning within the first few days of life. Formula-fed babies who drink less than 32 ounces per day also need supplementation. Severe deficiency can lead to rickets, a condition causing soft and weak bones.
My Baby Looks Bowlegged
Almost all babies are born with bowlegs because of how they were curled up in the womb. This is completely normal and usually corrects itself by age 2-3 as your child grows and starts walking. True bowleggedness that needs treatment is rare and usually only a concern if it's severe, gets worse over time, or affects just one leg.
Related Resources
Frequently asked questions
Is rickets in babies (vitamin d bone disease) normal?
When should I call the doctor about rickets in babies (vitamin d bone disease)?
When is rickets in babies (vitamin d bone disease) normal?
What causes rickets in babies (vitamin d bone disease)?
What should I mention to my pediatrician about rickets in babies (vitamin d bone disease)?
Is rickets in babies (vitamin d bone disease) normal at 0-3 months?
Is rickets in babies (vitamin d bone disease) normal at 3-12 months?
Should I go to the ER for rickets in babies (vitamin d bone disease)?
Does rickets in babies (vitamin d bone disease) go away on its own?
References
- [1]American Academy of Pediatrics. Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents. Pediatrics. 2008;122(5):1142-1152. AAP
- [2]National Institutes of Health. Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals. 2023. NIH
- [3]American Academy of Pediatrics. Vitamin D: On the Double. HealthyChildren.org. AAP
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Rickets in Babies (Vitamin D Bone Disease).
Things to mention
- Describe when you first noticed rickets in babies (vitamin d bone disease) and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your breastfed baby has not been receiving vitamin D supplementation and you notice widened wrists, prominent rib bumps, or worsening bowed legs.
- Mention if your baby's fontanelle seems unusually large or has not shown any signs of closing by 18 months.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Your breastfed baby has not been receiving vitamin D supplementation and you notice widened wrists, prominent rib bumps, or worsening bowed legs
- Your baby's fontanelle seems unusually large or has not shown any signs of closing by 18 months
- Your toddler has bowed legs that are getting worse rather than improving, especially with a restricted diet or limited sun exposure
Urgent signs to report immediately
- Your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care
- Your child sustains a fracture from a minor fall or normal activity, suggesting significantly weakened bones that need urgent evaluation
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
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Related Resources
Bottom line
Most cases of rickets in babies (vitamin d bone disease) are normal. Talk to your pediatrician if your baby or toddler develops muscle spasms, twitching, or seizures, which can result from dangerously low calcium levels as a complication of severe rickets and require emergency care.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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Related Medical Concerns
Vitamin D Deficiency in Babies
Vitamin D is essential for calcium absorption and healthy bone development. Breast milk alone does not provide adequate vitamin D, so the AAP recommends all breastfed and partially breastfed infants receive 400 IU of vitamin D daily beginning within the first few days of life. Formula-fed babies who drink less than 32 ounces per day also need supplementation. Severe deficiency can lead to rickets, a condition causing soft and weak bones.
My Baby Looks Bowlegged
Almost all babies are born with bowlegs because of how they were curled up in the womb. This is completely normal and usually corrects itself by age 2-3 as your child grows and starts walking. True bowleggedness that needs treatment is rare and usually only a concern if it's severe, gets worse over time, or affects just one leg.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.
Adrenoleukodystrophy (ALD) in Babies
X-linked adrenoleukodystrophy (X-ALD) is a genetic disorder affecting about 1 in 17,000 newborns, caused by mutations in the ABCD1 gene on the X chromosome. It primarily affects boys and impairs the breakdown of very long-chain fatty acids (VLCFAs), which accumulate and damage the myelin sheath in the brain and the adrenal glands. The most severe form, cerebral ALD, typically affects boys between ages 4-10 with rapid neurological decline. Newborn screening now enables early detection, and hematopoietic stem cell transplant or gene therapy performed before significant brain involvement can be life-saving.