Argan, jojoba, rosehip, shea, coconut, grapeseed. On the shelves, they look like variations of the same product, and in common perception, “plant oil” is taken as a guarantee of gentleness. In reality, the difference between one oil and another is as great as that between two different active ingredients, and it depends almost entirely on one thing: which fatty acids it contains.
In summary
- Plant oils and butters are triglycerides: they differ in the types of fatty acids they contain.
- Oils rich in linoleic acid are lighter and suited to blemish-prone skin; those rich in oleic acid are more nourishing and suited to dry skin.
- An oil doesn’t hydrate: it contains no water. It limits water loss, which is something else.
- Essential oils have nothing to do with plant oils: they are volatile, fragrant extracts with different usage guidelines.
Article written by Elisa Avalle, founder of LeLang Skin Care and dermocosmetics specialist. Cover image generated with the support of artificial intelligence.
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What’s inside a plant oil
Oil pressed from seeds or fruit is made largely of triglycerides, that is, three fatty acids bound to a glycerol molecule. The profile of those fatty acids determines everything: fluidity, absorption rate, stability over time, and affinity with skin lipids.
Alongside the triglycerides is a small unsaponifiable fraction containing vitamin E, sterols, polyphenols, and carotenoids. It makes up a very small proportion by weight, but gives the oil its antioxidant properties and often its color.
Oleic and linoleic acids: the distinction that matters
Oleic acid is a monounsaturated fatty acid: it makes oil feel richer and more occlusive, but when applied in large amounts to already fragile skin, it can disrupt the barrier lipids.
Linoleic acid is polyunsaturated and a component of skin ceramides. Acne-prone skin has often been observed to have sebum relatively low in linoleic acid, and some studies have evaluated topical application specifically on this skin type. This leads to a practical rule: for blemish-prone skin, linoleic oils; for dry skin, oleic oils.
| Oil or butter | Predominant fatty acid | Which skin types |
|---|---|---|
| Grapeseed, sunflower, hemp | Linoleic acid | Combination, blemish-prone, young |
| Rosehip | Linoleic and linolenic acids | Blemishes, discoloration, mature skin |
| Argan, sweet almond, hazelnut | Balanced oleic and linoleic acids | Almost all skin types; a good starting oil |
| Olive, avocado | Oleic | Very dry skin; not for reactive facial skin |
| Coconut | Lauric | Body and hair; may be occlusive on the face |
| Jojoba | It is not a triglyceride: it is a liquid wax | All skin types, highly stable |
| Shea, cocoa, mango butter | Stearic and oleic | Dry patches, lips, body |
Pages on individual oils are already on the site: argan, jojoba, coconut, rosehip, grapeseed, hazelnut, shea butter.
An oil is not a moisturizer
This is the costliest misconception. Hydrating means adding or retaining water, and oil contains no water. What it does is slow evaporation: if you apply it to skin that is already dehydrated and dry, it seals in nothing. Oil makes sense over a water-based product or on slightly damp skin.
If your skin feels tight but oily, the problem is almost always water, not oil: see the difference between dry or dehydrated skin.
The comedogenicity question
Lists that assign every oil a score from 0 to 5 are based on tests conducted decades ago, applying the pure substance to rabbit ears. The model has long been criticized: the species is not comparable to humans, and the dose has nothing to do with that in a real formula.
The only oil worth exercising real caution with is coconut, which is rich in lauric acid and is indeed occlusive for many facial skin types. Otherwise, the right question is about the finished product and your skin, not a table score.
Rancidity: the problem no one talks about
The richer an oil is in polyunsaturated fatty acids, the more beneficial it is for the skin and the more vulnerable it is to oxidation. Rancid oil changes smell and, when applied to the face, becomes a source of oxidative stress instead of an antioxidant.
- Store them away from light and heat, preferably in dark glass.
- A dropper bottle lets air in every time you use it: more practical, less stable.
- Vitamin E on the label (Tocopherol) is not just an active ingredient: it’s the antioxidant that protects the oil itself.
- Jojoba and saturated butters are the most stable; polyunsaturated seed oils are the most delicate.
Vegetable oils and essential oils are not related
A vegetable oil is a pressed fat; an essential oil is a volatile, concentrated extract made up of aromatic molecules. The former can be used neat on the skin; the latter never should: it must be diluted and is among the most common causes of contact dermatitis. Find usage guidelines in the essential oils guide.
How we use them
Our cleansing oil is based on sunflower, sweet almond, hazelnut and grapeseed oils: a deliberately more linoleic than oleic profile, because it needs to dissolve sebum and makeup without leaving a heavy film on skin that is then cleansed a second time.
CLEANSING GENTLE OIL Makeup-removing facial cleansing oil non-comedogenic, the first step of double cleansing Dissolves makeup, including... Discover CLEANSING GENTLE OIL
Frequently asked questions
What’s the difference between one vegetable oil and another?
Vegetable oils and butters are made mostly of triglycerides, and what sets them apart is the type of fatty acids they contain. This profile determines their fluidity, how quickly they absorb, their stability over time and their affinity with the skin’s lipids. They also contain a small unsaponifiable fraction, with vitamin E, sterols, polyphenols and carotenoids, which gives the oil its antioxidant properties and often its color.
Which vegetable oil should you choose for blemish-prone or dry skin?
A practical rule of thumb is to look at the fatty acids. For combination or blemish-prone skin, oils rich in linoleic acid are recommended, such as grapeseed, sunflower and hemp oils. They are lighter and have an affinity with the skin’s ceramides. For dry skin, choose oils richer in oleic acid, which are more nourishing. Argan, sweet almond and hazelnut oils have a balanced profile and are a good starting point for almost all skin types.
Does vegetable oil moisturize the skin?
No, because oil contains no water. What it does is slow down evaporation, so there’s little moisture to retain on skin that’s already dehydrated and dry. It works best applied over a water-based product or onto slightly damp skin. If your skin feels tight but looks oily, it’s usually water, not oil, that’s lacking: in that case, a good moisturizer is needed first.
Are plant oils comedogenic?
Tables that give each oil a score from 0 to 5 are based on old tests conducted with the pure substance on rabbit ears, a model long criticized for being far removed from human skin and the doses used in a real formula. The oil that warrants real caution is coconut oil, which is rich in lauric acid and can be occlusive on many facial skin types. For the rest, the finished product is what matters.
How should you store plant oil to keep it from going rancid?
Keep away from light and heat, preferably in dark glass. A dropper is practical, but lets air in with every use. Oils rich in polyunsaturated fatty acids are the most fragile, while jojoba and saturated butters are the most stable. Tocopherol on the label protects the oil itself from oxidation. Rancid oil changes smell and becomes a source of oxidative stress on the skin.
The next step
If an oil left your skin shiny or with a few more blemishes, before deciding that oils aren’t for you, check which oil it was. At LeLang partner pharmacies and parapharmacies, you can try the texture before choosing.
Not sure which oil is right for your skin?
Book a free virtual consultation: we’ll start with your skin type, not the latest trend.
Sources for this article
- Lin T.K., Zhong L., Santiago J.L., International Journal of Molecular Sciences, 2018: review of the anti-inflammatory and barrier-repair effects of plant oils applied to the skin.
- Letawe C., Boone M., Piérard G.E., Clinical and Experimental Dermatology, 1998: evaluation of the topical application of linoleic acid to microcomedones.
- Draelos Z.D., DiNardo J.C., Journal of the American Academy of Dermatology, 2006: critical review of the concept of comedogenicity.
- Regulation (EC) No. 1223/2009 on cosmetic products, INCI nomenclature for ingredients of plant origin.
Where to go next: Prickly pear oil · Rice bran oil · Dry or dehydrated skin
Discover the products: Facial cleansers · Sensitive skin
