One of the most common questions readers send us is whether a facial oil can replace a moisturiser. The honest answer is: sometimes, for some skin, in some seasons. To see why, it helps to know what a moisturiser is made of.
The three jobs of a moisturiser
Dermatologists usually describe moisturising ingredients in three groups:
- Humectants, such as glycerin, urea and hyaluronic acid, draw water into the outer layer of the skin.
- Emollients, such as many plant oils, esters and fatty alcohols, soften and smooth the surface.
- Occlusives, such as petrolatum, dimethicone and some waxes and butters, form a film that slows water loss.
A typical cream or lotion combines all three, in a base that is mostly water. A pure plant oil covers mainly the second job and a little of the third. It does not contain water or humectants.
When an oil alone can be enough
If your skin is normal to slightly dry, the air is reasonably humid and you apply the oil to skin that is still damp after cleansing, an oil can be enough. The damp skin supplies the water and the oil helps hold it there.
When you probably need both
- In cold, windy weather or in heated and air-conditioned rooms where humidity is low.
- If your skin feels tight within an hour of applying an oil.
- If you use drying treatments such as retinoids or benzoyl peroxide.
- If you have eczema-prone skin, in which case a doctor-recommended emollient should come first.
Low humidity is the big one. Desert cities and long hours indoors under strong air conditioning, the climate of most casino floors, can leave even oily skin feeling parched. Our Las Vegas desert-climate guide looks at that environment in detail.
Combining them well
The easiest method is to apply moisturiser first, then press a few drops of oil on top in the evening. Alternatively, mix one or two drops of oil into your moisturiser in the palm of your hand. Either way, keep sunscreen as the final morning step.
A note on "natural"
Plant oils are not automatically gentler than a well-formulated cream. Some people react to specific oils, and many oil blends contain essential oils that can irritate. A fragrance-free moisturiser from a pharmacy is often the kinder choice for reactive skin.
