There are two key actives required for managing hyperpigmentation (dark spots, age spots, or whatever you want to call them): patience and diligence. A third requirement is to have realistic expectations. I haven’t yet found the killer app for hyperpigmentation, but I have finally come to the breakthrough conclusion that there is a regimen, rather than a single product application, that is required to make any inroads on fading dark spots. If I’m right then I hope to make greater advances in the coming months. But I’ll come back to that in a second.
First, you need to appreciate that hyperpigmentation is stubborn. It has taken years, probably most of your adult life, to form. Mostly it comes down to melanocyte activity. There are typically between 1000 and 2000 melanocytes per square millimeter of skin and make up about 5% to 10% of the cells in the basal layer of epidermis (incidentally, black and white skins possess the same number of melanocytes).
Freckles, for example, are red patches due to hyperactive melanocytes that start in infancy, particularly in fair skins, and on exposed areas of the epidermis. Chloasma, also known as pregnancy mask, is due to excessive melanocyte activity forming symmetrical patches on the face in pregnancy or as a result of oestrone/progesterone therapy. Senile-lentigines or liver spots are brown patches on the forearms, face and hands due to a proliferation of melanocytes.
After doing a fair amount of reading on the subject, I have come to the conclusion that my approach which has been try to tackle dark spots with some kind of melanin or tyrosinase inhibitor is limited. And that’s certainly been my experience. I try fading and brightening creams, successful fading is limited, I get bored and give up. The better approach is a regimen: 1) exfoliate the damaged skin, 2) protect new skin from further sun damage, 3) use a melanin inhibitor and 4) give the regimen a big boost a few times a week with green LED light therapy.
Come to think of it, Lumixyl has a glycolic peel, brightening cream and a sunscreen. I now think all those stages are necessary. However, I do understand that most of us don’t like to feel locked into an entire range and I think its fine to mix and match with your favorite exfoliator (some kind of glycolic peel - Juice Beauty ($45 in the shop) or La Vie Celeste ($60 in the shop) to name a few - or an antioxidant/exfoliator such as Your Best Face Prep would be ideal) and sunscreen.
Regarding the melanin inhibitor, there are a confusing number of actives to choose from and so here’s a rundown of some of the most common.
Hydroquinone is an effective inhibitor of melanogenesis. But it achieves this by being cytoxic to melanocytes. Concerns about cancer have restricted the use of hydroquinone in Europe and Japan. Generally, these days, people try to find alternatives.
Tyrosinase inhibitors are alternatives to hydroquinone that are considered safer. Melanin forms through a series of oxidative reactions involving the amino acid tyrosine in the presence of the enzyme tyrosinase. Hence, some actives focus on inhibiting tyrosinase.
One such active is decapeptide-12, a synthetic peptide comprising a sequence of amino acids developed by dermatological researchers at Stanford University.
SymWhite 377 (phenylethyl resorcinol) is a synthetic compound partly derived from natural lightening compounds in scotch pine bark. Studies have shown that it is effective at brightening skin without harmful side effects.
Arbutin (hydroquinone-beta-D-glucopyranoside) A glycosylated hydroquinone found at high concentrations in certain plants and capable of surviving extreme and sustained dehydration, arbutin has been shown to inhibit melanin synthesis by inhibition of tyrosinase activity. A one-month study on 80 Chinese women, using a 1% alpha arbutin concentration, resulted in a “skin lightening effect”. It was faster and more effective than kojic acid (see below).
Glabridin (licorice extract) inhibits tyrosinase activity of melanocytes without cytotoxicity. Having said that, most of the research on licorice extract is on its antioxidant properties.
Magnesium ascorbyl phosphate is a non-irritating, stable form of vitamin C. It can be used at concentrations as low as 10% to suppress melanin formation.
Hexylresorcinol: In vivo studies conducted on .5% hexylresorcinol in 2007 demonstrated lightening results that were just as effective as 2% hydroquinone over an eight-week period.
Cinnamomum subavenium is one to look out for. As Sarah reported, two chemicals have been isolated from this plant that can block tyrosinase at only a 1% concentration. As far as we know, it hasn’t yet made it into cosmetic products, but we will be excited to try it out when it does.
Some hyperpigmentation actives that, for various reasons, might be best avoided include:
Azelaic acid is a rather weak competitive inhibitor of tyrosinase in vitro. In addition, azelaic acid has an antiproliferative and cytotoxic effect on melanocytes.
Kojic acid decreases melanin content, but it is dose dependent (at 1% or less, it doesn’t work) and at higher doses can be a strong irritant.
Retinoids such as tretinoin and adapalene are derivatives of vitamin A. The mechanisms for reducing pigmentation include inhibition of tyrosinase induction, interference with pigment transfer, and acceleration of epidermal turnover. They also have the ability to disperse pigment granules within keratinocytes. Retinoids may act as penetration enhancers when used with other lightening agents such as hydroquinone and mequinol. The most common adverse effects include burning, stinging, erythema, dryness, and scaling. Although the adverse effects are reversible, retinoid use may result in hyperpigmentation, especially in dark-skinned individuals.
I'm going to be working on my exfoliate, protect, inhibit and light therapy hyperpigmentation regimen and will report back as I find (hopefully) combinations of products that work.