Sodium Hydroxymethylglycinate or SHG, is often described as “naturally” derived from glycine, an amino acid. However, in order to get to the point where it can be used in a product, it must go through a rigorous manufacturing process using lots of chemicals, including formaldehyde.
SHG is also thought to break down into formaldehyde in the body - which is a problem if the product you are using is a moisturiser, designed to be absorbed into the skin. Products containing Sodium Hydroxymethylglycinate may irritate your skin and are best avoided.