These changes represent our best considered responses to three major issues regarding folate. Choline was increased to more effectively take advantage of the use of piracetam. It is a key substrate for making acetylcholine, a neurotransmitter. It is also key in making cell membranes. There is no toxicity issue with the higher doses, except that a small amount of hyperactivity is noted in some children for a short period of time until they adapt to the higher level of choline.
Excesses are harmlessly urinated out of the body.
Betaine is trimethylglycine. Mammals have an alternative pathway for conversion of homocysteine to methionine that uses betaine as a methyl donor. The byproduct is dimethylglycine. None of these agents is harmful. The purpose of this addition is to try to keep homocysteine, in conjunction with the folate-B12 pathway, in the form of methionine to rob CBS of substrate for overproduction of cysteine.