What is Sodium Hydroxymethylglycinate?

Sodium Hydroxymethylglycinate – or SHMG, for less of a mouthful – is a chemical preservative commonly found in cosmetics that helps prevent bacterial or fungal growth.

Many customers turn to Pai as a result of reactions to their skincare, something this ingredient is known for. So here’s our guide to what it is, its side effects and whether it’s safe for your skin.

What is Sodium Hydroxymethylglycinate?

Sodium Hydroxymethylglycinate is a preservative, though it can also be used as a skin-softening agent.

It can be a skin irritant in high doses, and should therefore only be found in cosmetic products at a concentration of 0.5% or less.

Sodium Hydroxymethylglycinate is classed as a Formaldehyde-releasing agent. It does this in order to achieve its preserving function on the final cosmetic product. However, this can be bad news for your skin.

Formaldehyde is a known carcinogen and a skin sensitiser, and Formaldehyde exposure – even to levels below 0.05% – could cause contact dermatitis in those with Formaldehyde allergies.

So why is it used in skincare? While parabens (commonly used preservatives) are often demonised, far more people are sensitive to Sodium Hydroxymethylglycinate. However, many manufacturers replace their paraben preservatives with this in an attempt to avoid any associated bad press, or to add a ‘paraben-free’ claim to their products.

Sodium Hydroxmethylglycinate is often described as 'organic' or naturally derived from glycine, an amino acid.

However, the ingredient goes through a rigorous manufacturing process involving several synthetic procedures (which, incidentally, is why it’s not COSMOS-approved).

Side effects

Sodium Hydroxymethylglycinate is one of a group of chemicals that are known to be associated with allergic contact dermatitis – so it’s safe to say it’s worth avoiding using it topically, whether you have sensitive skin or not.

Reactions usually entail a stinging or burning sensation, and reddening of the skin.

Sodium Hydroxymethylglycimate-free skincare

While many people come to organic skincare after reacting to chemicals in their usual products, finding a range laced with Sodium Hydroxymethylglycimate will certainly not solve the problem.

All of Pai’s products are formulated with sensitive skin in mind. That’s why we avoid using Formaldehyde-releasing preservatives, and indeed any other ingredient that could cause irritation.

Instead, we use only preservatives that are COSMOS-approved – and we go the extra mile by patch testing every single product on people with sensitive skin.

Sodium Hydroxymethlyglycinate is also listed as:

GLYCINE, N- (HYDROXYMETHYL) -. MONOSODIUM SALT;
GLYCINE, N- (HYDROXYMETHYL) -, SODIUM SALT;
N- (HYDROXYMETHYL) GLYCINE, SODIUM SALT;
N- (HYDROXYMETHYL) -. MONOSODIUM SALT GLYCINE;
SODIUM SALT GLYCINE, N- (HYDROXYMETHYL) -;
SODIUM SALT N- (HYDROXYMETHYL) GLYCINE;
N- (HYDROXYMETHYL) – SODIUM SALT GLYCINE;
SODIUM HYDROXYMETHYLGLYCINATE;
GLYCINE, N- (HYDROXYMETHYL) -, MONOSODIUM SALT;
HYDROXYMETHYLAMINOACETIC ACID,
SODIUM SALT;
SODIUM N- (HYDROXYMETHYL) GLYCINATE

For more advice, book in for a free skin consultation with one of our skin coaches