Results explain the renewed popularity of this skincare ingredient.
Of all the ingredients touted to improve your skin, the topical application of vitamin A derivatives stands up best to scrutiny. These retinoids have the ability to make skin look all shiny and new.
Therein lies the rub, for when retinoids first became widely used around the turn of the century they were prone to cause sensitivity, redness and flakiness, exacerbated by sun exposure. They could also leave skin looking plasticky - taut with a give-away strange sheen. So although they won early fans, including a host of alien-ethereal celebrity faces, many women were left feeling a little wounded and started looking for the next wonder.
Under the supervision of dermatologists, however, these tricky retinoids never really went away, because used in a controlled way they do deliver impressive results on tolerant, well-managed skins. Avowed fans include Madonna - who also shoots up her vitamins - and Gwyneth Paltrow.
Now, thanks to advances in formulation which have minimised skin irritation and made them more stable, they are enjoying a second wave of popularity. This has led to useful amounts in the form of retinol in more off-the-shelf products across the price ranges.
And no longer are they restricted to night-time use. British Vogue recently hailed "The Return of Retinol" in an article that said among skincare experts there was unmatched unanimity about the ingredient's anti-ageing effectiveness, continuing: "In today's world of peptides, growth factors, glacial water, and extracts from rare Corsican flowers, that's saying a lot."
My experience as a beauty writer is the same, time-after-time dermatologists say suncare first, then try skincare with vitamin A. Clinics here generally prescribe it in ascending strengths as skin becomes accustomed to its application. They also point out that prescription retinoid acid is usually in stronger doses than the more gentle retinol compound, which is capped at 2 per cent for cosmetic inclusion. In clinics, strengths may be double or triple this, but with higher doses comes a higher risk of reaction.
The move from clinic to counter sales, with products containing lower levels of the active ingredient, does mean any results are likely to be slower. If amounts are insignificant, results may be negligible. Earlier versions of retinol were often so unstable that many cosmetics products containing it were likely rendered ineffective.
That said, a ground-breaking study published in the British Journal of Dermatology several years ago showed that a product containing cosmetic retinol could match the performance of a prescription product. The one studied, Olay's Pro X Deep Wrinkle Treatment, is not available in New Zealand. Other new generation versions are, notably the innovative Neutrogena Rapid Wrinkle Repair range which usefully adds a day cream with sunscreen to the armoury and an eye-cream, both mainstream firsts.
French skincare range RoC stands out as one of the first to use retinol in commercial skincare and at luxury level La Prairie used it as a hero "time release" ingredient in its recent Cellular Power Charge Night Serum. There are also several boutique brands at maximum cosmetic strength, with others to come.
Cosmetic companies are not obliged to reveal ingredient percentages, but some who do claim effectiveness from 0.5 per cent retinol. American celebrity dermatologist Dr Fredric Brandt, who dispenses to the rich and famous, has a cosmetic sideline at the maximum 2 per cent level. His Glow by Dr Brandt Overnight Resurfacing Serum is expected here early next year.
Stockist Mecca Cosmetica is expecting its well-informed clients to be queuing up. It already has two full-strength options from Chantecaille and Perricone and store manager Chris Devlin says customers do seek them out. He recommends a 28-day Retinol Cure twice-a-season: "It will give you the very best skin you've ever had."
Mecca also stocks a retinol-laced line from another high-profile US derm, Dr Dennis Gross, but his approach is to mix it up with other ingredients, notably vitamin D. This he reckons is the way forward, made possible by retinol's new stability and gentleness.
Trade-offs in strength are balanced with lowered reactions when compared with retinoic acid because retinol can now be combined with skin-soothing ingredients. These include antioxidants and anti-inflammatories. At Chantecaille plant and nut oils give added hydration.
Neutrogena's parent company Johnson & Johnson won't talk retinol percentages in its products, saying most consumers have no frame of reference for what is high and low. The company told Viva, however, that its own testing during product development revealed preferences.
"J&J tested several concentrations and found that in the first four weeks of treatment higher concentrations showed more clinical improvement, but because there is more irritation associated with higher concentrations of retinol, the study subjects actually rated the formulations with lower levels of retinol as preferable. By the end of the study the subjects preferred the lower concentration formulas."
Clients in clinics are more likely to be offered a step up in strength. Most also recommend a mix of ingredients and treatment approaches for best results. Prescription Skincare in Remuera recommends combining prescription skincare with vitamin A peels for added effect, ideally in the winter months.
Whatever form you might favour to take your vitamin therapy, expect retinol to keep popping up in plenty more products. Use is advised at night, or in conjunction with a good sunscreen, SPF30+.
What it does
Retinol gives skin a more luminous, plumped look. It smoothes skin cells, improving tone and texture, making fine wrinkles and brown spots less obvious. It can even help lessen pre-cancerous lesions.
Retinol is less likely to cause irritation than retinoic acid. Both compounds are derivatives of vitamin A, a key human nutrient and anti-oxidant. Retinyl palmitate is another of a number of related compounds. Retinol was isolated first, but it was prone to degenerate when exposed to air and light so retinoic acid was developed.
Under the brand name Retin-A retinoic acid first won United States FDA approval in 1971 for prescription use in cream form to treat acne.
Dermatologists noticed it improved skin generally and over the past four decades more versions, under various brand names including Renova and Differin, have gained approval to be medically dispensed. (That's not something that can be readily said of most skincare).
The small retinoic acid molecule penetrates skin well, with an exfoliating effect, prompting cell turnover and collagen stimulation, but because of the reactions to it scientists revisited the milder retinol compound. They improved retinol's stability by micro-encapsulation, meaning degeneration is now less of an issue and it can better combine with other ingredients.
Cleverly it goes on inert, reducing the risks of redness and so being more suitable for sensitive skins. Retinol is activated by the skin itself, but not immediately, it penetrates and is stored in the cells, with a gradual conversion into retinoic acid. That is why some products talk about its being time-released.
Off the shelf
Ren Bio Retinoid Anti-Aging Concentrate $120, La Prairie Cellular Power Charge Night Serum $760, Neutrogena Rapid Wrinkle Resist Moisturiser SPF30 $38.95, Chantecaille Retinol Intense cream $206, Perricone MD High Potency Evening Repair $192.
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