Some people think that some individuals on the autism spectrum have a range of nutritional and metabolic problems. These include low levels of nutrients, high levels of oxidative stress (a chemical state within cells that can increase cellular damage) and difficulties with metabolic processes (such as digestion).
Some people think that these nutritional and metabolic differences may be the cause of some of the core features of autism (such as impaired communication and social difficulties) and related issues (such as challenging behaviours).
They also believe that by taking dietary supplements, such as dimethylglycine, they can reduce some of those symptoms. However the exact mechanism by which dimethylglycine might do this is unclear.
For example, Bolman and Richmond (1999) speculated that DMG might act as a neurotransmitter, changing the rate of amino acid activity in the brain, enabling it to work more effectively. Kern et al (2001), speculated that DMG might increase methylation, leading to a reduction in lactic acid build-up and enhanced oxygen use during times of hypoxia, enabling the body to work more effectively.
There have been numerous claims made for the use of dimethylglycine supplements as an intervention for people on the autism spectrum. For example:
Rimland (1990) reported “In some cases dramatic results have been seen within 24 hours: A Los Angeles mother was driving on the freeway, three-year-old Kathy in the back seat, five-year-old mute autistic son Sammy in the front. DMG had been started the day before. Kathy began to cry. Sammy turned and spoke his first words: ‘Don't cry, Kathy.’ The mother, stunned, almost crashed the car.”
The Autism Research Institute (2008) claims that “Many parents have reported that, within a few days of starting DMG, the child's behavior improved noticeably, better eye contact was seen, frustration tolerance increased, the child's speech improved, or more interest and ability in speaking was observed.”
Rimland also claims (2001) that “Over the past 40 years I have encountered a great many cases of severely SIB/A [self-injurious and assaultive behavior] individuals who have responded wonderfully well to nutritional supplementation, particularly high dose B6 and magnesium, and DMG.”