Does keto diet help autism

Autism spectrum disorder (ASD) is a lifelong neurodevelopmental disorder that is characterized by stereotyped behavior and deficits in communication and social interaction. Autism spectrum disorder affects 3.4–6.7 per 1,000 children. Boys are four times more likely than girls to have Autism spectrum disorder. The core features of Autism spectrum disorder patients are social communication deficits and repetitive sensory–motor behaviors. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM), patients who are diagnosed with Autism spectrum disorder must have persistent deficits in social communication and repetitive and unusual sensory–motor behaviors. Comorbidities in Autism spectrum disorder are common and include epilepsy, sleep disorders, gastrointestinal (GI) symptoms, and psychopathologies such as anxiety, depression, attention deficit hyperactivity disorder, and intellectual disability. Sleep disturbances occur in 50–80% Autism spectrum disorder children, and sleep disorder is associated with behavioral dysregulation. Epilepsy is also one of the most common comorbidities in Autism spectrum disorder children, and the average prevalence reaches 26%. Autism spectrum disorder individuals who have epilepsy are likely to exhibit more severe autism-related symptoms. GI symptoms, which range from 23 to 70% in ASD children, are related to the severity of Autism spectrum disorder. Approximately 31% of children with Autism spectrum disorder have intelligence quotient scores below 70. The cost of raising a child with Autism spectrum disorder is 1.4–3.6 million dollars according to the level of intellectual disability, and the largest expenses are special education costs and the loss of parental productivity. When children grow up, supportive living accommodations and the loss of individual productivity become the highest costs. Therefore, Autism spectrum disorder places a large burden on society and the affected families. There are no effective drugs for Autism spectrum disorder. Several interventions, such as special education and behavioral interventions, provide some benefits, but these interventions do not improve all core symptoms of Autism spectrum disorder and have less effects on comorbidities, including epilepsy. Therefore, new therapies are urgently needed to broaden the management options and improve the prognosis of these patients. Lower levels of disaccharidases and hexose transporters were found in Autism spectrum disorder patients with GI symptoms, which suggests carbohydrate digestion disorders as a physiopathological mechanism in Autism spectrum disorder patients. Therefore, a low-carbohydrate diet, such as a ketogenic diet (KD), is likely suitable for Autism spectrum disorder patients.

A ketogenic diet is a high-fat, appropriate-protein, and low-carbohydrate diet that has a positive effect on energy metabolism. For example, a ketogenic diet increases the levels of adenosine triphosphate (ATP) and enzymes associated with mitochondrial metabolic pathways and enhances mitochondrial biogenesis. Acetyl-CoA is converted to ketone bodies under the effects of d-β-hydroxybutyrate dehydrogenase, acetoacetate succinyl-CoA transferase, and acetoacetyl-CoA-thiolase. Ketone bodies, including β-hydroxybutyrate, acetoacetate, and acetone, function as fuels under fasting or starvation conditions and cross the blood–brain barrier (BBB) to feed the brain. These molecules also prevent mitochondrial permeability transition and attenuate reactive oxygen species (ROS). Therefore, ketone bodies have neuroprotective effects in the central nervous system (CNS). A ketogenic diet is a significantly effective treatment for epilepsy. Refractory epilepsy patients aged 1–18 years treated with a ketogenic diet for 4 months had a 56% reduction in mean seizure frequency. A ketogenic diet may also improve some core autistic features and comorbidities of Autism spectrum disorder, but data of clinical studies of a ketogenic diet as a treatment for Autism spectrum disorder are very limited. The present review examined the role of a ketogenic diet in Autism spectrum disorder treatment and discussed the underlying mechanisms.