We all know what a moisturiser is, right? Not so fast. Moisturisers mean a heap of different things and – as I recently found out- don’t actually have a scientific definition.
Having said that, broadly speaking you can divide moisturisers by their ingredients- into Emollients, Humectants and Occlusive ingredients¹. And they’re actually pretty different. So when choosing a moisturiser, you want to choose the ingredients your skin needs most.
Let me walk you through them now:
What they do: Attract water towards themselves increasing moisture content in the outer layer of the skin
Used for: Dry, rough and scaly skin
Downsides: May be tacky in feel and may irritate
Examples: Glycolic & Lactic Acid, Urea, Hyaluronic acid, Glycerin, Butylene Glycol, Glycerin
What they do: Create a barrier and reduce or prevent moisture loss from the skin
Used for: Dry and irritated skin
Downsides: Can feel greasy
Examples: Cetearyl Alcohol (fatty alcohol), Stearic Acid, paraffin
What they do: Soften, soothe and improve the appearance of skin (but don’t add moisture to the skin). Most have some occlusive property
Used for: Normal and Dry skin
Examples: Dimethicone, Cetearyl Alcohol (fatty alcohol), Jojoba
(Note: some ingredients have more than one function)
So how on earth do I work out which one I need?
Most moisturisers will include a few emollient ingredients (some more suited to dry skin and others to oilier skin) – the variable is the presence (or not) of humectants and occlusive as well.
Step one is to pick the right emollient for your skin type. Dimethicone, Glyceryl Stearate and Jojoba (to name 3 out of possibly a hundred or so!!) are lighter so more suited to oilier skins where Lanolin, Avocado oil and Shea butter (again, the full list is HUGE!!) are richer and more suited to drier skin.
Seriously dry skin? Dry and cracked/hardened skin and irritated skin really needs all three moisturizing types- so look for something with a rich emollient (see above) PLUS a humectant and occlusive ingredients.
Oily or combination skin? You still need a moisturizer especially in dry, windy weather or you sit in an air conditioned environment. Just avoid occlusive ingredients altogether- and go for light emollients.
If you’re not sure what kind of moisturiser an ingredient is, best just to ask google.
A number of moisturising ingredients may have safety concerns, so if you’re not sure, check the ingredients here.
Remember: Ingredients listed on a product label are shown in order of concentration from highest to lowest*. So if the ingredient you are looking for is towards the end of the list, there won’t be much of it in the product (which is the way it should be for some active ingredients, but generally not moisturising ingredients)
*for ingredients with a concentration > 1%
¹ Sethi et. Al 2016, Indian Journal of Dermatology