When selecting oils it is important to look at the fatty acid content.  Oils high in linoleic acid are very good for oily, combination and acne prone skin, but they are prone to going rancid quickly.  Butters are very occlusive and tend to have a longer shelf life. Their high Stearic and/or Palmitic acid content help lock in moisture so are good for dry and dehydrated skin.

When formulating creams it is important to have a balance of different oils and butters to create a cream that has a good skin feel. In the industry you will often hear people talk about spreading cascades to define the skin feel of a product.  This was coined by Henkel (now part of Cognis) and describes the different spreading values of emollients. Accordingly oils can be classified as fast, medium and slow spreading.  

A fast spreading oil will disperse quickly on the skin than a slower spreading oil. Using high amounts of fast spreading oils is likely to leave a very thin film on the skin leaving it soft however the effects will disappear quickly and may leave your skin feeling dry. Conversely using a high levels of slow spreading oils or butters will leave a fatty layer on the skin which is not likely to disperse quickly and will feel heavy. Using a combination of fast, medium and slow spreading oils will have a synergistic effect on the skin feel of the product as well as how long it is able to lock in moisture and keep the skin feeling supple.

Below is a basic guide to selecting different vegetable oils for your skincare products. This is based on my own observations and is somewhat subjective especially when we come to the fast and medium fast spreading oils. This is just a starting point and you may find that you disagree with some of my conclusions.

The Three Main Skin Types: Oily/Acne Prone, Sensitive, Dehydrated   

Mature Skin and Eye Care Products

F - Fast Spreading, VF - Very fast spreading, M- Medium spreading, S- slow spreading, VS - Very slow spreading, VVS - Very, very slow spreading