Sodium hydroxymethylglycinate is a relatively common ingredient in skin care products. The properties of the substance allow it to function equally well as an active ingredient to improve the look and feel of the hair or skin and as an additive to improve the quality of formulations. The ingredient may be referred to by a large number of other names, including n-sodium salt glycine, hydroxymethylaminoacetic acid sodium salt and sodium-n hydroxymethyl glycinate.
Some confusion exists about the origins and sources of sodium hydroxymethylglycinate. The ingredient is derived from the abundant, natural amino acid glycine. This nutrient is found in a variety of foods, including gelatin, pork, turkey, fish and eggs. Inside of the human body, glycine can be used to produce protein, which is a vital component of the hair and skin.
Unlike other ingredients that are made from amino acids, sodium hydroxymethylglycinate cannot be produced with a natural chemical reaction. Instead, glycine must be put through a series of synthetic modifications, alterations and reactions that do not occur in nature. As a result, it is correct to say that sodium hydroxymethylglycinate is naturally derived, but not an entirely natural ingredient.
This distinction is important because some skin care companies tout sodium hydroxymethylglycinate as a natural alternative to other ingredients that perform similar functions in skin and hair care products, such as parabens. While this is not a false statement, it can cause confusion among consumers.
When included in formulations as an active ingredient, sodium hydroxymethylglycinate is typically chosen by skin and hair care companies due to its ability to function as a humectant. This means that sodium hydroxymethylglycinate naturally draws moisture from the air because its molecules are attracted to those found in droplets of water. Once the moisture has been removed from the air, it can be absorbed by the hair or skin.
Sodium hydroxymethylglycinate’s properties as a humectant are useful for replacing lost moisture in the skin tissue to prevent or combat dryness. When contained in moisturizers and body lotions, sodium hydroxymethylglycinate helps to treat symptoms of dry skin, including itching, flaking and redness. Properly hydrated skin also appears fuller and plumper, and as a result, sodium hydroxymethylglycinate may be used in anti-aging products designed to make wrinkles less noticeable on the complexion.
For the hair, sodium hydroxymethylglycinate keeps the hair shafts supple and pliant, reducing the likelihood of breakage and split ends. Often, the ingredient is used in conditioners due to this effect. Dry hair is also more prone to fly-aways and static. As a result, sodium hydroxymethylglycinate is an effective ingredient in shampoos, conditioners and styling products meant to make the hair more manageable. By drawing moisture into the hair fibers, sodium hydroxymethylglycinate creates thicker, fuller strands with more bounce and lift, and so hair care brands may add the ingredient to volumizing products as well.
As an additive, sodium hydroxymethylglycinate functions as a preservative. Inside of skin and hair care products, the ingredient kills microbes, such as bacteria, mold and mildew. This allows products to remain potent and pure. Sodium hydroxymethylglycinate is often the preservative of choice among skin care companies because it is effective against a broad range of microbes and remains viable and stable in products of all different acidity levels.
In the United States, sodium hydroxymethylglycinate is approved for use in skin care products at concentrations of 0.5 percent or less, and at these levels, is considered as "Generally Regarded as Safe" by the U.S. Food and Drug Administration. The European Union has approved sodium hydroxymethylglycinate for use in beauty products at concentrations of up to 0 .5 percent as well.
Despite its approval, some concerns exist about the potential health consequences of sodium hydroxymethylglycinate. The ingredient is known to cause irritation to the eyes, such as redness and watering, and can produce burning and inflammation in those with sensitive skin.
In addition, some studies have raised the question as to whether sodium hydroxymethylglycinate can expose the body to formaldehyde, a toxin and cancer-causing agent. So far, clinical studies have found that sodium hydroxymethylglycinate is likely only to degrade into formaldehyde when products are improperly stored. The studies have also shown that the amount of formaldehyde given off by sodium hydroxymethylglycinate is typically at a concentration of less than .005 percent and that this tiny amount of formaldehyde would be unlikely to cause any health risks.