The relevance of choline for brain development is well established and choline supplementation has been used in a set of neurological diseases to improve brain outcomes [1, 2]. Choline supplementation in a mouse model of autism improved social interaction and anxiety-like behavior [3]. Rett Syndrome, the most common autism spectrum disorder in females, is a neurodevelopmental disorder characterized by an apparent healthy postnatal development, lasting until 6-18 months old, followed by a rapid regression in language, loss of motor skills, impaired social interaction, anxiety, and the onset of repetitive behaviors [4, 5]. Currently, there is no cure for Rett Syndrome; however, there is encouraging data that suggests that supplemental choline can help.  

In a mouse model of Rett Syndrome, supplementing infant pups with extra choline resulted in improved behavior [6]. In many people Rett Syndrome is caused by gene mutation that creates a metabolic roadblock in methylation. Methylation is important because it is needed to make many important molecules needed by brain, and also, it is needed to control the expression of many genes. Choline, folate and vitamins B12 and B6 are all involved in methylation and it may be that choline has some beneficial effects in autism because of its role in methylation. So far, the best evidence for a role for choline is based on studies in mice, but hopefully studies in people will begin soon.

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