The definition of moisture
We break it down for you in this article on moisture vs hydration, but as a quick recap: moisture = water. Moisturizers are something different: think of a moisturiser as an umbrella term for anything that adds water to your hair or skin or helps retain it once it's already there.
Can you moisturise your hair with just water?
Maybe in an ideal climate where the humidity level was just right all the time - and your hair was in 100% perfect condition.
That's not the case for most of us, but luckily, that's why moisturizing ingredients exist. They're here to help us with our hair hydration goals: moisture restoration and moisture retention.
Moisture restoration is just like it sounds: bringing in additional moisture to take our hair's water content back up to its ideal level. Moisture retention is all about holding onto that moisture - a tricky thing for hair on either extreme of the porosity scale.
The ingredients that help us do this function in very specific ways, but each falls into at least one of these categories:
What are humectants?
Humectants are hygroscopic ingredients - they have a tendency to absorb moisture from the air. They do this by forming hydrogen bonds with molecules of water, actively drawing it into your hair and skin.
Humectants use this power to increase your hair's water-binding capacity and control the rate of moisture evaporation from your hair. This is especially necessary for super low porosity, moisture resistant hair, which struggles to absorb the water it desperately needs to raise its low moisture levels.
Some humectants simply hold onto moisture, like glycerin. Others like guar gum and xanthan gum are known as film-forming humectants because they don't just hold onto moisture; they actually form a film that helps physically block moisture loss.
This type of humectants operate somewhere between conventional humectants and occlusives (more about them below).
Some common humectants are: glycerin, hyaluronic acid, sorbitol, lactic acid and propylene glycol, flax seed gel, dehydroxyxanthan gum, guar hydroxypropyltrimonium chloride, hydrolyzed proteins (also classed as rejuvenators), ceramides (also classed as rejuvenators).
Products that are rich in humectants: La Aplanadora Leave In, atrActiva Keratin Rich Conditioner (see Part 2 of this article for a full breakdown of their moisturizing ingredients).
What are emollients?
Emollients soften your skin and hair, replacing lost lipids and providing lubrication and protection. On your strands, they fill in the voids which make the surface irregular and rough, leaving it even and smooth.
Ingredients from very different sources with very different chemical structures and physical properties can all be emollients: seed and nut oils, fruit butters, fatty alcohols, esters, fatty acids, hydrocarbons, and synthetic polymers, including silicones and polyquaterniums.
Some common emollients: olea europaea (olive oil), butyrospermum parkii (shea butter), cetyl alcohol, cetyl esters, lauric acid, cera alba (beeswax), petrolatum, polyquaternium-7, behentrimonium methosulfate, dimethicone.
Products that are rich in emollients: MayOliva Treatment, Multivitamin Treatment, Capilo La Aplanadora Leave In.
What are occlusives?
DHA Hair Care Experts