Acne is generally thought of as an adolescent affliction, although my experience suggests otherwise. In my practice, I see a regular stream of individuals who continue to suffer from 'bad skin' long after puberty. In fact, statistics show that more than one in two women and 40 per cent of men over 25 have some acne, and for a few this problem persists into middle age. Traditional nutritional advice is to avoid fatty food, especially chocolate. However, recent evidence suggests it is not fat but another commonly found ingredient in chockie bars that incites the skin to break out.
Clues to the causes of acne may be found by comparing the nutritional habits of different populations. Researchers looked at the diets and dermatological health of two indigenous populations: the Kitavan islanders from Papua New Guinea and the Aché hunter-gatherers from Paraguay. While the Kitavans subsist mainly on fruit, vegetables, fish and coconut, the Aché diet is comprised almost entirely of wild, foraged-for and locally cultivated foods. Intriguingly, the prevalence of acne in both these groups eating essentially natural foods was found to be nil. This is in stark contrast to the high rates of acne seen in industrialised nations.
Some have suggested that such differing propensities to acne are a matter of genetics. However, the observation that populations swapping their traditional diet for something less natural become more acne-prone points strongly to nutrition as the critical factor. The typical Western diet is renowned for its high fat content and this supports the view that fatty foods cause spots. However, some researchers have put forward the notion that it is sugars and starches (carbohydrates) that are the major culprits in acne eruptions.
While carbohydrates in traditional diets generally come in whole, unadulterated forms, those consumed in the West are typically refined, and may contain a load of sugar. Eating a diet rich in foods such as white bread, biscuits, cakes, confectionery, sweet drinks and sugary breakfast cereals may have important implications for our skin.
One effect these foods have is to stimulate the production of copious quantities of insulin. Laboratory experiments show that rushes of insulin encourage the secretion of a skin waterproofing agent called sebum, and may initiate changes in the skin that block the glands that make it. It is this backlog of sebum, often coupled with a bacterial infection, that causes spots, pimples and acne. The evidence suggests that keeping the carbs in our diet based on natural sources such as fruits, vegetables, beans, pulses and brown rice makes for healthier skin.
The good news is that chocolate isn't necessarily off the menu: dark varieties containing 70 per cent or more cocoa solids are relatively low in sugar, and are therefore the treats of choice for those keen to keep their skin clear.