According to Gram Research analysis, about 14% of children with drug-resistant epilepsy on a ketogenic diet develop kidney stones, but most cases are asymptomatic and managed without surgery. A 2026 study of 80 children found that older age at diet start and higher-strength ketogenic ratios increased risk slightly, yet 60% of children achieved meaningful seizure reduction, suggesting the diet’s benefits often outweigh kidney stone risks when properly monitored.
Researchers studied 80 children with hard-to-treat epilepsy who followed a ketogenic diet or modified Atkins diet to control seizures. They found that about 14% of children on the ketogenic diet developed kidney stones, though most cases were caught early and managed without surgery. The good news: the diet still helped reduce seizures in 60% of patients. Older children and those on higher-strength ketogenic diets had a slightly higher risk, but regular monitoring allowed most kids to continue their seizure-fighting diet safely.
Key Statistics
A 2026 cohort study of 80 children with drug-resistant epilepsy found that 13.8% (11 children) developed kidney stones or calcium deposits while on a ketogenic diet, with all cases managed conservatively without surgical intervention.
In a 2026 analysis of 80 children on ketogenic diet therapy, 60% experienced meaningful seizure reduction (more than 50% fewer seizures), while children who developed kidney stones were significantly older at diet initiation (p = 0.025).
A 2026 single-center study found that zero children on the modified Atkins diet developed kidney stones compared to 13.8% on the full ketogenic diet, though the modified Atkins group was small.
Among 80 children with drug-resistant epilepsy studied in 2026, only 4 patients required interruption of ketogenic diet therapy due to kidney stones, and no patients needed surgical intervention for stone removal.
The Quick Take
- What they studied: Whether children taking a ketogenic diet for seizure control develop kidney stones, and what factors increase this risk.
- Who participated: 80 children with drug-resistant epilepsy (seizures that don’t respond to medications) who started either a ketogenic diet or modified Atkins diet at a hospital in Saudi Arabia.
- Key finding: About 1 in 7 children (14%) on the ketogenic diet developed kidney stones or calcium deposits in their kidneys, but most cases had no symptoms and were managed without surgery.
- What it means for you: If your child needs a ketogenic diet for seizure control, kidney stone risk exists but is manageable with regular check-ups and imaging. The seizure benefits often outweigh the risks, especially with proper monitoring.
The Research Details
This was a retrospective cohort study, meaning researchers looked back at medical records of children who had already been treated. They followed 80 children with drug-resistant epilepsy who started either a ketogenic diet (a high-fat, low-carb diet that changes how the brain uses energy) or a modified Atkins diet (a similar but slightly less strict version). The researchers tracked what happened to these children over time, recording their diet details, medications, blood work, and kidney imaging results.
The study collected information about each child’s age when starting the diet, how strict their diet was (the ‘ketogenic ratio’), how long they stayed on the diet, what seizure medications they took, and whether they used carbonic anhydrase inhibitors (a type of medication that can affect kidney stone risk). Researchers then compared children who developed kidney stones to those who didn’t to find patterns and risk factors.
This approach is useful because it examines real-world outcomes in actual patients rather than testing something new in a controlled lab setting. However, because researchers looked backward at existing records rather than following patients forward, they couldn’t control all the variables that might affect results.
Understanding kidney stone risk is important because the ketogenic diet is one of the few proven non-medication treatments for children whose seizures don’t respond to drugs. If doctors and families know which children are at higher risk and how to monitor for problems, they can use this helpful seizure treatment more confidently. This study provides practical information that helps doctors make informed decisions about whether the benefits outweigh the risks for each individual child.
This study has several strengths: it included a reasonable number of children (80), used objective measures like kidney imaging to detect stones, and tracked multiple potential risk factors. However, it was conducted at a single hospital, so results may not apply everywhere. The study was also relatively small, which means some findings (like the trend toward higher ketogenic ratios increasing risk) didn’t reach statistical significance. Additionally, the modified Atkins diet group was very small, making comparisons difficult. The researchers acknowledged these limitations and were appropriately cautious in their conclusions.
What the Results Show
Among the 80 children studied, 11 (13.8%) developed kidney stones or calcium deposits in their kidneys during follow-up, while 69 children (86.2%) had no kidney problems. Importantly, all 11 children with kidney stones were on the full ketogenic diet—none of the children on the modified Atkins diet developed stones, though this group was very small.
Children who developed kidney stones tended to be older when they started the diet (average age around 6-7 years versus younger children without stones). The study also found a trend suggesting that children on higher-strength ketogenic diets (a ratio of 3:1 or higher, meaning more fat relative to carbohydrates and protein) had slightly more kidney stone risk, though this difference wasn’t quite statistically significant.
Most importantly, the kidney stones were often asymptomatic—meaning children didn’t feel sick or have pain. Doctors caught them through routine imaging. Management was almost entirely conservative, meaning doctors simply monitored the stones rather than removing them surgically. Only four children needed to stop the ketogenic diet because of kidney stones.
Regarding seizure control, the diet worked well: 60% of all children in the study experienced meaningful seizure reduction (more than 50% fewer seizures). This suggests the diet’s benefits for seizure control were substantial even with the kidney stone risk.
The study found that several factors did NOT significantly increase kidney stone risk, including: use of carbonic anhydrase inhibitor medications, the underlying cause of epilepsy, whether children could move around normally, how they received nutrition (by mouth versus feeding tube), how long they stayed on the diet, and the number of seizure medications they took. This is reassuring because it suggests doctors have some flexibility in how they manage these children without dramatically increasing stone risk.
Previous research has documented that ketogenic diet can increase kidney stone risk in children, with reported rates ranging from 6% to 13% in different studies. This study’s finding of 13.8% falls within that expected range. The finding that older children have higher risk aligns with some previous research. However, this study adds important new information by showing that with regular monitoring and conservative management, most children can continue the diet safely. The fact that no children in this study required surgery for kidney stones is encouraging compared to some earlier reports.
This study has several important limitations. First, it looked at only 80 children at one hospital in Saudi Arabia, so results may not apply to all children everywhere. Second, the modified Atkins diet group was very small, making it hard to fairly compare the two diets. Third, because researchers looked backward at medical records rather than following children forward, they couldn’t control for all factors that might affect kidney stone development. Fourth, the study didn’t have a control group of children not on any special diet for comparison. Finally, the follow-up time varied between children, so some were monitored longer than others.
The Bottom Line
For children with drug-resistant epilepsy, the ketogenic diet remains a reasonable treatment option with strong evidence of seizure benefits. However, regular monitoring is essential: children should have kidney ultrasounds at baseline and periodically during treatment, blood work to check kidney function and metabolic markers, and urine testing. Starting the diet at younger ages and using moderate ketogenic ratios (rather than the highest ratios) may reduce kidney stone risk. If kidney stones develop, they can usually be managed without stopping the diet. Confidence level: Moderate to High (based on this study plus consistent findings in previous research).
This research is most relevant for: children with drug-resistant epilepsy and their families considering ketogenic diet therapy, pediatric neurologists and epilepsy specialists, pediatricians managing children on ketogenic diets, and families already using this diet who want to understand monitoring needs. Children with normal kidney function starting the diet at younger ages may have lower risk. Those with pre-existing kidney problems should discuss risks carefully with their doctor.
Kidney stones can develop at any point during ketogenic diet therapy, but the study didn’t specify average time to stone formation. Most stones in this study were asymptomatic and caught on routine imaging rather than causing symptoms. Benefits for seizure control typically appear within weeks to months. Regular monitoring (ultrasounds every 6-12 months) is recommended to catch any problems early.
Frequently Asked Questions
Does the ketogenic diet cause kidney stones in children with epilepsy?
The ketogenic diet increases kidney stone risk in some children—about 14% develop stones according to a 2026 study of 80 children. However, most stones are asymptomatic and managed without surgery, and the diet’s seizure benefits often justify the risk with proper monitoring.
What age children are most likely to get kidney stones on a ketogenic diet?
A 2026 study found that older children at diet initiation had significantly higher kidney stone risk compared to younger children. Researchers recommend considering diet start age when weighing risks and benefits.
Can my child continue the ketogenic diet if kidney stones develop?
Yes, in most cases. A 2026 study found that only 4 of 11 children with kidney stones needed to stop the diet, and no children required surgery. Regular monitoring allows continued therapy in most patients.
How often should my child get kidney imaging if on a ketogenic diet?
The 2026 research suggests regular renal surveillance and routine kidney imaging facilitate early detection. Discuss specific monitoring schedules with your child’s neurologist, but baseline imaging and periodic follow-up ultrasounds are typically recommended.
Is the modified Atkins diet safer for kidneys than the ketogenic diet?
A 2026 study found zero kidney stone cases in children on the modified Atkins diet versus 13.8% on the full ketogenic diet, suggesting lower risk. However, the modified Atkins group was very small, so larger studies are needed to confirm this difference.
Want to Apply This Research?
- Track monthly seizure frequency, dietary adherence (ketogenic ratio maintained), and scheduled kidney ultrasound/lab test dates. Record any urinary symptoms (pain, blood in urine, urgency) immediately.
- Set reminders for scheduled kidney monitoring appointments and blood work. Log daily water intake to support kidney health (aim for age-appropriate hydration). Record seizure events to demonstrate diet effectiveness to your medical team.
- Create a dashboard showing: seizure reduction percentage over time, adherence to ketogenic ratio targets, completed kidney imaging and lab results with dates, and any symptoms reported. Share monthly summaries with your neurologist to optimize diet management.
This research summary is for educational purposes only and should not replace professional medical advice. Decisions about ketogenic diet therapy for children with epilepsy should be made in consultation with a pediatric neurologist or epilepsy specialist who can evaluate your child’s individual risk factors, medical history, and needs. If your child is on a ketogenic diet, follow your doctor’s recommended monitoring schedule for kidney function and imaging. Seek immediate medical attention if your child experiences symptoms of kidney stones (flank pain, blood in urine, urinary urgency) or any concerning symptoms.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.