What are they?
Retinoids (retinol, tretinoin, etc) are compounds similar to vitamin A, the one we receive with food from liver and carrots. Retinol is a popular type of retinoids.
What are they good for?
Retinoids are some of the most powerful anti-aging ingredients that are currently known to cosmetic industry. They control skin-cell division and trigger synthesis of structural proteins which keep the skin elastic and bouncy. Retinoids were also reported to even the skin tone, have mattifying and anti-blemish effects. They are also frequently used for anti-acne therapy.
The queen of retinoids is retinoic acid or tretinoin – it is the most potent agent out of the whole group, but it also causes a lot irritation. It is considered to be ten times more potent than retinol. Other retinoids like isotretinoin or retinaldehyde are similar compounds that will be converted to tretinoin by your skin. These additional conversion steps can be advantageous. They allow the ingredient to act slower and so are milder on the skin.
**Unlike natural retinoids, tazarotene is not converted to tretinoin in the skin and acts a bit differently. It is good for reducing pigmentation, fine wrinkles, and skin roughness.
Another interesting retinoid is adapalene, which was synthetized recently. It is quite effective against acne, as it has anti-inflammatory properties.
Here is the list of retinoids currently used in skin care: tretinoin (retinoic acid), retinaldehyde, retinol, isotretinoin, alitretinoin, etretinate, acitretin, adapalene, tazarotene, bexarotene, seletinoid G.
Good to know
Some of the retinoid products are so strong that they require prescription.
Retinoids make skin more sensitive to the sun, so sunscreen is a must when using retinoid.
Using retinoids require patience. Usually clear effect is seen after regular use for 3, or better 6 months
In general retinoids are quite unstable. But no panic - just keep them dark. E.g. if stored away from sunlight, ideally in the fridge, tretinoin is effective after 3 months of use. Retinol-palmitate and tretinoin-palmitate are more photo-stable than pure retinol or tretinoin.
Retinoids can cause irritation. It is more common with tretinoin and tazarotene than with isotretinoin, adapalene, retinol, and retinaldehyde. But no long term side effects have been observed. So careful introduction into skin routine, e.g. application once week with slow increase in frequency and concentration is the best way to go.
Again, remember always use sunscreen after a retinoid application.
If you are PREGNANT or trying to conceive, get advice from your doctor, but might be best to omit use of retinoids altogether.