Vitamins are amazing for your body, but what do they do when you rub them on your skin? Earlier we looked at vitamin C and what it does - now let's take a gander at vitamin A, one of the most amazing products for your skin!
Vitamin A is found in vegetables (such as carrots), egg yolk, liver and fish oil. It actually isn't one compound, but a range of different, related compounds which all act similarly in the body, and are generally referred to as retinoids. There are also some synthetic retinoids which do the same thing too. One of the most widely found retinoids, retinol, is shown below:
Vitamin A has a lot of important functions in the body, including in the eye and the immune system. It's also important in skin health.
Retinoids have been used since the 1970s for treating acne. It's mainly used as a cream that's applied to skin - retinoids used this way include retinoic acid, retinyl palmitate, isotretinoin, tretinoin, retinol and tazarotene. It can also be taken as tablets - the most commonly used is isotretinoin (Roaccutane). Retinoids reduce sebaceous gland size and secretion, and reduces the amount of bacteria in the skin, which is one of the main causes of acne! It suppresses keratinisation - in other words, it reduces the chances of dead skin cells clumping together and causing clogged pores. It also reduces inflammation (redness and swelling).
Creams containing retinoids have also been found to decrease signs of photoageing (sun damage) such as wrinkles, dark spots and roughness. It works mainly by enhancing the rate of skin repair, and increases collagen temporarily - but once you stop using it, the damage can quickly come back!
Rosacea and psoriasis can also be treated with oral retinoids. Taking retinoid tablets has also been shown to slow down the progress of some skin cancers.
However, long term use of retinoids can sometimes result in a lot of unpleasant side effects, and you can even overdose on them! It can dry out your skin completely, cause hair loss and damage your liver. It's also a teratogen (affects your baby if you're pregnant), and can give you headaches, nausea, gastrointestinal problems and weak bones. Topical vitamin A is much safer, with irritated and flaky skin (dermatitis) being the main side effect, but in some cases it might not be enough.
One of my favourite skin products, rose hip oil, is full of vitamin A! :)
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