Methyl Donor

A compound that contributes a methyl group (–CH₃) to biochemical reactions, serving as a substrate for methyltransferase enzymes. Methyl donation is essential for DNA methylation, neurotransmitter synthesis, homocysteine remethylation, and the synthesis of creatine and phosphatidylcholine. Key dietary methyl donors include betaine (trimethylglycine), choline, folate (Vitamin B9), and Vitamin B12. In supplement formulation, betaine anhydrous (Section 47) is the most commonly used dedicated methyl-donor ingredient.