I get a lot of random questions emailed to me, so I’ve decided to share some of those questions with my answers here as well, just in case you were wondering the same thing.
I choose my oils for a variety of reasons. The main things I look for are their benefits to skin, shelf life, and cost. Let’s tackle shelf life and cost first!
Various oils have various longevities. For example, unrefined hemp seed oil has a shelf life of only 2 months. While unrefined hemp seed oil is a lovely oil, and I *am* able to slightly extend its life with Vitamin E, such a short lifespan makes me very nervous. First of all, I don’t know how long the product has been sitting on a manufacturer’s shelf before it makes it to me. Second, I would need to use all of the oil in a relatively short time. And third, my customers would be receiving a product with an already short lifespan- only 2 months in a best case scenario. Personally, I have so many products that I almost never make it through something within 2 months.
Cost factor is definitely another consideration. There is a reason you see a lot of the same oils used from soaper to soaper- it’s because they provide excellent skin benefits at a reasonable cost. Olive oil, shea butter, coconut oil, palm kernel oil, and sweet almond oil are among commonly seen soaping oils. These are relatively inexpensive but yield a great bar of soap. It’s unusual to see rarer, exotic oils such as sea buckthorn, pomegranate, and calendula oil in soap. These are premium oils that come at premium prices. I could certainly make a bar of soap with one of these oils, but the cost would be passed onto the customer, and it can be argued how much of the benefit you even get out of the premium oil once it’s saponified (made into soap). This isn't to say that some of these oils are not worth the extra money- they certainly can be! They would be more appropriately used in a body butter or facial serum, and possibly worth every penny of the product!
Every oil has a unique feel and unique qualities. An oil can feel light or heavy, astringent or greasy. Oils can be high or low on a comedogenic scale (likeliness to clog pores). Oils have unique fatty acid profiles, polyphenols, and polysterols. WAIT, STAY WITH ME!! I promise to keep this painless. =)
Among other things, an oil’s fatty acid profile tells us some of the benefits to skin that the oil provides. For example, an oil with high oleic acid will be well-absorbed by our skin, moisturizing, anti-inflammatory, and regenerative. An oil with high linoleic acid may improve your skin’s barrier functions, prevent scaling, and even reduce acne!
Oils also contain an array of polyphenols and polysterols. Polyphenols may sound familiar from reading about the benefits of drinking green tea, red wine, and eating dark chocolate. Polyphenols also provide benefits when applied topically. Polysterols are a plant’s equivalent of the cholesterol found in our own skin. Each oil brings its own polyphenols and polysterols to the table, and these should be considered when formulating your creation.I won’t go into any more detail here, but I highly recommend doing more research online! It’s definitely overwhelming, so feel free to ask me in person, too. (But don’t be surprised when I pull out my notebook!)