some oils can penetrate our skin to offer an improvement to skin's barrier lipids, that polyphenols can penetrate our skin to behave as anti-oxidants, and that phytosterols probably don't penetrate our skin, but it's okay because they help our skin by increasing its barrier properties. So let's get back to Rosi's original question - is there any reason to use expensive oils in our products?
I think we need to do a bit more defining! (Yeah, I know, I'm a babbler. You ask me the time, I tell you how to build a clock, but it's not an easy question!) What is an expensive oil? I think it can be defined as an oil that costs more than our carrier oils. For instance, I pay $5.25 for 16.9 ounces/500 ml for soy bean oil and $7.50 for 60 ml/2 ounces of evening primrose oil, so it's safe to say that evening primrose oil could be considered an expensive oil. But there are good reasons for using each of these oils.
Evening primrose oil contains gamma-linoleic acid, which is great for improving skin's barrier repair mechanisms and reducing transepidermal water loss. It contains some nice polyphenols and phytosterols, but not a lot of Vitamin E.
Soybean oil contains a lot of linoleic acid, which is great for improving skin's barrier repair mechanisms. It contains a lot of phytosterols, which will help with inflammation, loads of polyphenols, and loads of Vitamin E, which is a great skin softener.
But for all of that, soybean oil can feel really greasy on our skin while evening primrose oil can feel dry. If you hate the skin feel of soybean oil, all the awesome-ness it offers is irrelevant.
We could do comparisons for tons of different oils and in the end, it comes down to what qualities you want in your product and what skin feel you want. I think the key is knowing your ingredients - knowing what they contain and knowing how they feel - so you can make educated decisions.
When researching your oils and butters, don't believe the hype. I can't count how many websites I came upon touting this oil or that one as the ultimate oil for all your problems, when the reality is that each oil offers something different to the formulator. As awesome as evening primrose might be, I can find really good arguments for using pumpkin seed oil, rice bran oil, pomegranate oil, and so on.
I know I harp on about it, but take some time to get to know the skin feel of your oils. (Click here for the series on this topic.) Spend some time in your workshop getting to know them! You won't regret spending the time on oils and butters because they are such an essential part of products from lotions to conditioners to anhydrous products.
To finally answer the question "is there a reason to use expensive oils in our products?" Yes, I think there is. And there are reasons not to use expensive oils, too. That's the very vague short answer. For the long answer, check out the posts from the last week!
Join me tomorrow for more fun formulating!