Scurvy, a vitamin C deficiency disease, is reappearing in Japanese children with autism spectrum disorder who eat very limited diets, according to a 2026 nationwide study of 47 cases. Research shows that 96% of affected children had selective eating habits, 72% had autism, and 88% presented with walking difficulties rather than weight loss, leading to delayed diagnosis in 30% of cases. Early dietary assessment and vitamin C level testing can prevent serious complications.
Scurvy, a disease caused by vitamin C deficiency that was common centuries ago, is making a comeback in Japan among children with autism spectrum disorder and other developmental conditions. According to Gram Research analysis of a nationwide study, nearly half of the 47 children identified with scurvy had autism and ate very limited diets. The research shows that doctors often miss this diagnosis, and some children undergo unnecessary and potentially harmful tests before getting the right treatment. Understanding the warning signs and checking vitamin C levels could help catch this preventable disease earlier.
Key Statistics
A 2026 nationwide Japanese study of 47 children found that 96% of scurvy cases occurred in children with selective diets, and 72% had autism spectrum disorder.
According to a 2026 research analysis of 47 Japanese children with scurvy, 88% presented with gait disturbance as their primary symptom, yet only 21% showed weight loss.
In a 2026 study of childhood scurvy across 35 Japanese hospitals, 30% of cases were initially misdiagnosed and 38% of children underwent potentially harmful examinations before correct diagnosis.
A 2026 Japanese multicenter study found that 77% of children with scurvy had vitamin C levels below the detection limit, indicating severe deficiency.
The Quick Take
- What they studied: How often scurvy appears in Japanese children, who gets it, what symptoms they have, and why doctors sometimes miss the diagnosis.
- Who participated: 47 children from 35 hospitals across Japan who were diagnosed with scurvy between 2014 and 2023. Most were around 3.6 years old, mostly boys, and about 72% had autism spectrum disorder.
- Key finding: Nearly all children with scurvy (96%) ate very selective diets, and 30% were initially misdiagnosed. The most common symptom was difficulty walking or moving normally, not weight loss as doctors might expect.
- What it means for you: If your child has autism or another developmental condition and eats a very limited diet, talk to your doctor about vitamin C intake. Watch for unusual walking problems or joint pain, which could signal scurvy. Early detection prevents serious complications.
The Research Details
Researchers sent surveys to 407 pediatric hospitals across Japan asking if they had treated children with scurvy from 2014 to 2023. Hospitals that said yes received a detailed follow-up questionnaire asking about symptoms, how the disease was diagnosed, treatments given, and how children recovered. The researchers also searched medical literature for additional cases. This two-step approach helped them gather information from real patient experiences across the entire country.
The study collected information about each child’s age, sex, weight, diet history, underlying medical conditions like autism, symptoms when they arrived at the hospital, blood test results, what tests were done, treatments received, and outcomes. By looking at all these details together, researchers could identify patterns in how scurvy appears in Japanese children and why it’s sometimes hard to diagnose.
This research approach is important because scurvy is so rare in developed countries that individual doctors may never see a case in their entire career. By collecting information from many hospitals across Japan, researchers could gather enough cases to understand the real patterns. This helps doctors recognize scurvy faster and avoid unnecessary tests that might harm children.
The study included all confirmed cases from major hospitals across Japan over a 10-year period, making it representative of the actual problem. However, the study relied on hospitals remembering and reporting cases accurately, which could mean some cases were missed. The sample size of 47 children is small but reasonable for such a rare disease in developed countries. The study was published in a peer-reviewed medical journal, meaning other experts reviewed the methods and findings.
What the Results Show
The study found 47 children with scurvy across Japan, with a median age of 3.6 years and 70% boys. Nearly all children (96%) had very selective eating habits, eating only a few types of food. About 72% had autism spectrum disorder, while 13% had no known underlying condition.
The most striking finding was that 88% of children had gait disturbance, meaning they had trouble walking or moving normally. This was the most common symptom, yet only 21% had weight loss. This pattern is important because doctors might expect a malnourished child to be thin, but these children often looked normal in weight.
Blood tests showed that 77% of children had vitamin C levels below the detection limit, meaning they were severely deficient. However, 30% of children were initially misdiagnosed, meaning doctors thought they had a different disease. Additionally, 38% underwent potentially harmful examinations, such as unnecessary biopsies or imaging tests, before the correct diagnosis was made.
Only 36% of children had a low body mass index, meaning most appeared to have normal weight despite severe vitamin C deficiency. This is important because it shows that scurvy can develop even in children who don’t look obviously malnourished. The study also found that careful dietary assessment was the key to diagnosis, since nearly all children had selective eating patterns.
Scurvy is historically known as a disease of sailors and people with severe malnutrition, but this study shows it’s reappearing in developed countries among children with autism and selective eating habits. Previous research has noted increasing scurvy cases in developed nations, but this is the first large Japanese study documenting the specific characteristics and diagnostic challenges. The finding that gait disturbance is the most common symptom differs from historical descriptions and highlights why modern doctors might miss the diagnosis.
The study included only 47 children, which is a small number. Some hospitals may not have reported cases they treated, so the actual number of children with scurvy in Japan might be higher. The study looked backward at cases from 2014 to 2023, so doctors’ memories of details might not be perfect. The study was conducted in Japan, so results might differ in other countries with different populations and healthcare systems.
The Bottom Line
Parents and caregivers of children with autism or selective eating should ensure adequate vitamin C intake through diet or supplements (strong evidence). Doctors should consider scurvy in children with selective diets who have unexplained walking problems or joint pain (strong evidence). Blood tests for vitamin C levels should be done early if scurvy is suspected to avoid unnecessary harmful tests (strong evidence).
Parents of children with autism spectrum disorder or other developmental conditions that cause selective eating. Pediatricians and family doctors who treat children with developmental disabilities. Caregivers in schools or facilities serving children with autism. Children with any condition causing very limited food intake.
Symptoms of scurvy develop gradually over weeks to months as vitamin C stores deplete. Once vitamin C supplementation begins, symptoms typically improve within days to weeks. Full recovery usually takes several weeks to a few months depending on severity.
Frequently Asked Questions
Can scurvy still happen in modern developed countries?
Yes. A 2026 Japanese study found 47 children with scurvy between 2014 and 2023, mostly with autism who ate very limited diets. Scurvy can develop in any child lacking adequate vitamin C, regardless of living in a wealthy country.
What are the early warning signs of scurvy in children?
According to 2026 research, the most common early sign is gait disturbance (difficulty walking), occurring in 88% of cases. Other signs include joint swelling, bruising easily, and irritability. Weight loss is less common than expected.
Should children with autism be screened for vitamin C deficiency?
Children with autism who eat selective diets should have vitamin C intake assessed by their doctor. A 2026 study found 72% of scurvy cases involved autistic children with limited food variety, suggesting dietary evaluation is important.
How is scurvy diagnosed and treated?
Blood tests measure vitamin C levels. A 2026 study found 77% of affected children had levels below detection limits. Treatment involves vitamin C supplements or dietary changes. Early diagnosis prevents complications like permanent joint damage.
Why do doctors sometimes miss scurvy diagnosis?
A 2026 study found 30% of scurvy cases were initially misdiagnosed because walking problems are unusual presentations. Doctors may not expect scurvy in developed countries or in children who appear normally weighted.
Want to Apply This Research?
- Log daily food intake for children with selective diets, specifically tracking vitamin C sources like citrus fruits, berries, tomatoes, and leafy greens. Set weekly reminders to note any changes in walking ability, joint swelling, or unusual bruising.
- If your child has a selective diet, work with a pediatrician or nutritionist to add vitamin C-rich foods they’ll accept, or discuss vitamin C supplements. Track which foods are accepted and gradually introduce new options. Monitor for warning signs like difficulty walking, swollen joints, or easy bruising.
- Monthly check-ins with your child’s doctor if they have selective eating patterns. Keep a food diary showing vitamin C intake. Document any physical changes in mobility or joint function. Annual blood work to check vitamin C levels for high-risk children.
This article summarizes research findings and is not medical advice. Scurvy is a serious medical condition requiring professional diagnosis and treatment. If you suspect your child has scurvy or vitamin C deficiency, consult a pediatrician immediately. Do not attempt to diagnose or treat scurvy without medical supervision. This information is intended for educational purposes and should not replace professional medical evaluation, diagnosis, or treatment.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.