Chemical peels are an ancient practice. Abrading the skin and / or introducing an abrasive topical agent dates back to prehistoric times. While the methods have been refined, whether it’s a pumice stone followed by soured milk in 4000BC or a lactic acid peel today, the concept remains the same – to resurface and rejuvenate the skin.
What is a peel? By inducing a controlled injury to the skin’s surface, a chemical peel works by removing the upper layer or layers. The skin’s natural healing process then works to generate a new, smoother surface – thus reducing acne scarring, fine lines and other contour issues. The ultimate goal of a skin peel is an improvement in texture along with a reduction in discolouration. Depending on the type of peel, skin shedding can be significant and last days, or – as is commonly the case today – can be minor. In the past skin peels were preceded by exfoliation or abrasion to enhance the chemical’s effect – today the peel solution alone is often sufficient.
Throughout history and across the world skin peels evolved along similar lines. Ancient Egyptians would abrade their skin with alabaster, a soft white stone, and follow up with topical solutions made with acids, oils and salt. The Romans and Greeks used pumice stone and resin and graduated to sulphur for serious results. Gypsy populations developed the deep chemical peel – their early experimenting was the forerunner for the phenol peel, a medical grade resurfacing treatment sometimes requiring a general anaesthetic. It was in the 19th century however that skin peels really has their moment, with a sharp increase in experimentation led by Austrian dermatologist Ferdinand Hebra, founder of the Vienna School of Dermatology. Various processes were trialled (including hair-raising experiments with lime and nitric acid) before the tincture – a mix of various chemicals with alcohol – became the prototype of the modern chemical peel.
Today, popular peels usually involve either alphahydroxy or betahydroxy acid, with deeper peeling agents used for specific conditions. While the science behind these chemicals is sophisticated its surprising how direct the link is to the past. Alphahydroxy acid for instance forms the basis of many common treatments like the glycolic peel. AHAs include lactic, citric and tartaric acids – all of which have their roots in the age-old cosmetic use of sour milk, sour grapes and citrus juices. Betahydroxy acid peels like the salicylic peel are used to control acne – harking back to the the ancient Indian practice of applying wintergreen, an aromatic plant high in BHA, to control skin oil.
Skin peels today are highly refined – absorption rates, penetration and after effects continue to improve. With ongoing efforts to minimise trauma while enhancing results, the skin peel is safer and more effective than ever. Many deeper and more complex treatments are the result of modern research – retinoic acid based peels and TCA for example are 20th century discoveries – but the basics of the skin peel remain unchanged and our debt to the past, and to the long chain of trial and error which got us here, remains.