The Ketogenic Diet and Epilepsy: A Difficult Balance
As far back as ancient Greece, physicians noticed that fasting could reduce seizure activity. In the 1920s, doctors at the Mayo Clinic developed the ketogenic diet to reproduce the benefits of fasting without complete food deprivation. By sharply limiting carbohydrates and emphasizing fats, the body shifts from using glucose for energy to burning fat and producing ketones, molecules that may help calm overactive nerve cells (Rho, 2017).
For nearly a century, the ketogenic diet (KD) has served as a powerful medical tool for treating epilepsy. For people whose seizures don’t respond to medication, it offers another path that can be life changing when it works, though not without its challenges.
Why Diet Matters in Epilepsy
Epilepsy affects the brain’s electrical system, causing recurring seizures. Roughly one third of people with epilepsy don’t respond to medication (Kwan et al., 2009). For them, doctors often consider alternative treatments such as surgery, nerve stimulation, or dietary therapy like the ketogenic diet.
What the Diet Looks Like
The classic ketogenic diet is extremely high in fat, about 90 percent of calories, with only small amounts of protein and very few carbohydrates. It is a precise and demanding prescription, often measured to the gram by medical professionals.
Patients are closely monitored by a neurologist and dietitian since even a small dietary slip can disrupt ketosis and bring seizures back.
How It Helps
The diet seems to work through several pathways:
It stabilizes the brain’s energy supply, keeping neurons from over firing.
It boosts certain neurotransmitters like GABA, which calm brain activity (Wang et al., 2003).
It may reduce inflammation and alter gut bacteria in ways that protect the brain (Olson et al., 2018).
About half to two thirds of patients who stay on the diet experience fewer seizures, and some stop having them altogether (Kossoff et al., 2018). For people who have exhausted all other treatments, that is a remarkable improvement.
When the Cure Creates Its Own Problems
Yet a diet that pushes the body into a constant state of ketosis is not without its downsides. Short-term issues such as fatigue, nausea, constipation, dehydration, or low blood sugar are common during the first weeks. Over time, more serious effects can develop from nutrient imbalances, deficiencies and metabolic changes.
• High cholesterol and triglycerides: Imbalanced macronutrient intake can raise cardiovascular risk.
• Nutrient deficiencies: Limited fruits, vegetables, and grains reduce intake of fiber, B vitamins, selenium, and magnesium. Supplements help, but are not foolproof (Kossoff et al., 2018; Armeno et al., 2014).
• Kidney stones: Metabolic changes can raise calcium levels in urine, increasing stone risk and contributing to metabolic acidosis (Kossoff et al., 2009; Bergqvist et al., 2005).
• Bone loss: Chronic acidosis and calcium loss can weaken bones and increase fracture risk (Bergqvist et al., 2008).
• Slowed growth in children: Low calorie or protein intake can slow physical development and growth (Armeno et al., 2014).
• Mood and cognition changes: Irritability, brain fog, or poor concentration may result from altered glucose metabolism and micronutrient gaps (Zare et al., 2017; Lutas & Yellen, 2013).
• Metabolic acidosis: A buildup of ketones can strain the kidneys and bones (Kossoff et al., 2009).
• Fatty liver or pancreatitis: Constant fat metabolism may overwork the liver and pancreas, occasionally leading to inflammation (Sharma & Jain, 2014; Liu et al., 2018).
• Heart rhythm disturbances: Low selenium or magnesium levels can weaken heart muscle or disrupt rhythm, and severe deficiency has been linked to sudden cardiac events (Bank et al., 2008).
• Hormone disruptions: Missed periods, low thyroid activity, and fertility changes can occur with prolonged restriction and altered energy metabolism (Paoli et al., 2013).
• Gut microbiome imbalance: Limited fiber and plant foods can disrupt digestion and reduce beneficial bacteria in the gut (Olson et al., 2018).
Even for adults, sticking to the diet long term can become socially and emotionally draining. Eating becomes math, not pleasure. The diet’s rigidity can isolate people, and the psychological weight of constant vigilance should not be underestimated.
Modern Compromises
Because of these challenges, newer versions like the Modified Atkins Diet (MAD) and the Low Glycemic Index Treatment (LGIT) were developed.
The Modified Atkins Diet loosens the rules, allowing more protein and calories while keeping carbs extremely low. It is easier to follow but still triggers ketosis. Studies show similar seizure control with fewer side effects (Kossoff et al., 2006; Liu et al., 2018).
The Low Glycemic Index Treatment focuses on choosing carbs that digest slowly and keep blood sugar steady. It is less likely to cause nutrient deficiencies and may be more sustainable long term (Pfeifer & Thiele, 2005).
These modified plans represent a middle path, less punishing though sometimes less potent.
A Difficult Balance
For people with drug resistant epilepsy, the choice is not between healthy and restrictive eating. It is between ongoing seizures that can cause injury, cognitive decline, or even death, and a demanding diet that may offer relief.
The ketogenic diet is not a simple fix. It replaces one set of risks with another and requires medical oversight, patience, and support. Yet for those who regain seizure control, the trade can be life changing.
In the end, the ketogenic diet occupies a gray space, not fully medicine and not fully lifestyle. It reminds us that health rarely deals in absolutes. Sometimes the best we can do is choose carefully, monitor closely, and live fully within the compromises that bring safety and an improved quality of life.
References
Armeno, M. et al. (2014). National consensus on the ketogenic diet. Rev Neurol, 59, 213–223.
Auvin, S., & Nabbout, R. (2011). Le Régime Cétogène Chez L’Enfant. Montrouge: John Libbey Eurotext.
Bank, I. M., Shemie, S. D., Rosenblatt, B., Bernard, C., & Mackie, A. S. (2008). Sudden cardiac death in children receiving the ketogenic diet: Possible role of selenium deficiency. Pediatrics, 122(2), e326–e330.
Bergqvist, A. G. C., Schall, J. I., Gallagher, P. R., Cnaan, A., & Stallings, V. A. (2005). Fasting versus gradual initiation of the ketogenic diet: A prospective, randomized clinical trial of efficacy. Epilepsia, 46, 1810–1819.
Kossoff, E. H., McGrogan, J. R., Bluml, R. M., Pillas, D. J., Rubenstein, J. E., & Vining, E. P. (2009). Optimal clinical management of children receiving the ketogenic diet: Recommendations of the International Ketogenic Diet Study Group.Epilepsia, 50, 304–317.
Kossoff, E. H., Zupec-Kania, B. A., Auvin, S., Ballaban-Gil, K. R., Bergqvist, A. G. C., Blackford, R., et al. (2018). Optimal clinical management of children receiving dietary therapies for epilepsy: Updated recommendations of the International Ketogenic Diet Study Group. Epilepsia Open, 3, 175–192.
Liu, H., Yang, Y., Wang, Y., Tang, H., Zhang, F., Zhang, Y., et al. (2018). Ketogenic diet for treatment of intractable epilepsy in adults: A meta-analysis of observational studies. Epilepsia Open, 3, 9–17.
Lutas, A., & Yellen, G. (2013). The ketogenic diet: Metabolic influences on brain excitability and epilepsy. Trends Neurosci, 36, 32–40.
Olson, C. A., Vuong, H. E., Yano, J. M., Liang, Q. Y., Nusbaum, D. J., & Hsiao, E. Y. (2018). The gut microbiota mediates the anti-seizure effects of the ketogenic diet. Cell, 173, 1728–1741.
Paoli, A., Rubini, A., Volek, J. S., & Grimaldi, K. A. (2013). Beyond weight loss: A review of the therapeutic uses of very-low-carbohydrate (ketogenic) diets. Eur J Clin Nutr, 67, 789–796.
Rho, J. M. (2017). How does the ketogenic diet induce anti-seizure effects? Neurosci Lett, 637, 4–10.
Sharma, S., & Jain, P. (2014). The modified Atkins diet in refractory epilepsy. Epilepsy Res Treat, 2014:404202.
Zare, M., Okhovat, A. A., Esmaillzadeh, A., Mehvari, J., Najafi, M. R., & Saadatnia, M. (2017). Modified Atkins diet in adults with refractory epilepsy: A controlled randomized clinical trial. Iran J Neurol, 16, 72–77.
Written by Kim Johnson, RD, LN | Owner
Kim specializes in: Eating disorders, disordered eating patterns, IBS, nutrition management for neurodivergent individuals - ADD/ADHD and autism spectrum disorder, weight concerns and supporting those ready to move past chronic dieting.