Dimethylglycine and Trimethylglycine (commonly known as DMG and TMG), are classified as a food substance rather than a vitamin. It is found in very small amounts in brown rice and liver. The benefits of taking DMG or TMG range from behavioural changes, reduction of seizures,and decreased obsessive-compulsive behaviours to improved language
DMG and TMG have been reported from thousands of families to be quite beneficial to many individuals with autism. Similar to vitamin B6 and magnesium, DMG and TMG are safe, relatively inexpensive, and help about half of the children and adults with autism. It should be noted that some kids tolerate DMG but not TMG. Also note that whichever one of these is used, it needs to be balanced with folic acid and vitamin B12.
Research on humans and laboratory animals has shown that DMG and TMG enhance the effectiveness of the immune system. Some children and adults with autism have seizures, and there are two published reports of decreases in seizure activity as a result of DMG
Two studies have shown no improvements from DMG in individuals with autism, however at least one of the studies used only half the recommended dose. A double-blind placebo-controlled study by Drs. Shin-siung Jung, Bernard Rimland, and Stephen M. Edelson involving 84 participants documented a significant decrease in behavioural problems.