Rosehip oil is believed to contain trans-retinoic acid or tretinoin, a form of Vitamin A. You'll see this on every site about rosehip oil. But a recent study failed to find this compound, which is odd considering every write up you see on this oil mentions it, and the oil shows the ability to reduce scarring and reduce hyper pigmentation of them. It is believed to be the very active ingredient in rosehip oil, so I guess more studies need to be done.
Rosehip oil has been used for quite some time in traditional medicine as a cell regenerating, wound healing, and scar lessening ingredient, and studies are bearing this out. Studies on photo-aging and scar repair show rosehip oil - used at as little as 6% of a formula - can reduce fine wrinkles causes by UV damage and reduce hyperpigmentation of scars. Why is this? It was thought these wondrous powers were due to the trans-retinoic acid - it is likely from all the free radical scavengers, anti-oxidants, tannins, and carotenoids!
Rosehip oil does contain Vitamin C and beta-carotene (the precursor to Vitamin A), both of which are anti-oxidants or free radical scavengers. The beta-carotene gives the oil a yellow-ish colour. And rosehip oil feels a little dry because of all those tannins, making it a more astringent or non-greasy oil when compared to something like sunflower oil.
Despite all these wonderful polyphenols, phytosterols, and fatty acids, rosehip oil is not a good choice for people with breakout prone skin. It is known to make acne worse, and can cause breakouts! Sorry!
It would appear that using a CO2 extract of rosehip oil has its benefits. One study showed higher levels of linoleic and linolenic fatty acids, with a reduction of oleic acids, in a CO2 extracted oil. The oil is also a darker colour, which seems to indicate the presence of more carotenoids.
Because of all those wonderful unsaturated bonds, rosehip oil has a shelf life of about 6 months. Keep it in the fridge or freezer, and make a note of the "best before" date for your products.
So what does rosehip oil offer? Some great anti-oxidants and free radical scavengers, lovely moisturizing and softening from oleic acid, skin barrier repair and anti-inflammatory properties from linoleic and linolenic acid, the possibility of some reduction of fine lines and signs of photo-aging, and scar reduction. Sounds pretty good to me! Add 0.5% Vitamin E to your creations to extend the life of the oil.
Apparently the ideal amount for rosehip oil in a facial product is 6%. Try it in a facial serum at up to 10% (I've already included in the dry skin serum recipe!) Or try it in a facial moisturizer like this one at 6%. You could substitute it for the hempseed oil and still get all that lovely linoleic acid.
Join me tomorrow for more oil related merriment!