Ginger has a hunch about humectants: I’ve heard that that humectants only work if there’s a high moisture level in the air and other wise they’ll draw the moisture out of your hair. Is this possible?
The Right Brain replies: Humectant is a very misused word in the beauty industry. Many people use “humectant” interchangeably with “moisturizer” when in reality the two are very different. Let’s take a look.
How do humectants work?
Humectants are different from regular moisturizers because they are able to attract and hold onto water molecules. Chemicals that have this ability are said to hygroscopic. Examples of hygroscopic, or humectant, cosmetic ingredients include glycerine, sorbitol and propylene glycol. What do these ingredients have in common that allow them pull moisture from the air? They all have multiple OH (Oxygen and Hydrogen) groups that interact with water molecules in a process called hydrogen bonding. Chemicals that have multiple OH groups are known as polyols. Whew! Enough with the chemical vocabulary let’s get on with the answer to your question.
Can humectants cause dry skin?
If humectants can attract moisture from the air, can they also pull it out of your hair or skin? In theory, yes. If you were in a very dry climate and you slathered on a pure humectant (glycerine for example), the OH groups could pull moisture from the deeper layers of your skin up to the surface where it could evaporate. So in this particular example, a humectant could actually cause your skin to become drier.
Fortunately, skin lotions don’t contain pure humectants; they also contain water, emollients, occlusive agents and other water binding chemicals. Water provides an immediate burst of moisture to the upper layers of skin while the other ingredients help prevent water from evaporating from your skin. So the chances of the humectant having a drying effect on your hair or skin is pretty slight.
The Beauty Brains bottom line
Hair and skin lotions are formulated with multiple moisturizing agents. Even products like Gly-Miracle Skin Humectant cream contain more than just humectants. So you don’t have to worry about these lotions sucking you dry.
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Hydrating dry skin with skin moisturizers is essential.
The lipids of the epidermis play a vital role in healthy normal skin, as they help the stratum corneum to regulate natural water loss. If they are removed by harsh soaps or detergents, or by damage such as a burn, the skin loses some or all of its ability to retain water, becomes dry and will start to break down.
The epidermis also contains natural enzymes, which are important for getting rid of old skin cells. Enzymes need moisture in which to work, so dryness (desiccation) of the stratum corneum worsens dry and unhealthy looking skin.
If alcohol makes up a large proportion of the product, then that too has a drying effect.
Some beauty brands (especially natural or organic ones) use alcohol as a preservative – instead of chemical ingredients, such as Parabens or Formaldehyde.
However, for alcohol to effectively preserve a moisturising cream, it must make up a minimum of 20% of the product – and in some products it can be substantially higher.
Alcohol in such high concentrations not only dries the skin, but can trigger skin irriation too.
All this information is so confusing to me. What ingredients should I look for if I need a good moisturizer?
Petrolatum, mineral oil, glycerin and cetyl alcohol
The problem with hair products is when you apply them to the hair, they have the time to dry after several hours. My fear is that it start drawing the moisture from my hair once the hair lotion has dried out. Unless the humectant really prevents it from drying out no matter how long it is in the hair even during winter time. Do i have it wrong?
Petrolatum, mineral oil, glycerin and cetyl alcohol – are you kidding!!!! these are the things you want to most avoid.
amanda, what source led you to believe those ingredients are to be avoided?
I wouldn’t avoid petrolatum, mineral oil, glycerine and cetyl alcohol.
They don’t break me out and they’re pretty good. I’m good with almost any moisturizer that lists water first then glycerine.
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