• Andrés Martínez, science journalist

    Detoxing the skin: a myth

    26 May

    Detoxing is all the rage and detox products number in their dozens on shop shelves. Countless diets propose eliminating toxins from the body by all possible means. It may well be that many of these means are healthy, but the skin does not accumulate toxins and neither can toxins be easily eliminated through the skin.


    Today, detoxifying the body and its organs is an obsession. We are offered diets, exercises and treatments aimed at purifying our bodies from within. We are also told that certain products applied to our skin will not only remove toxins, but will also cleanse our insides.


    Natural body cleansing

    The human body detoxifies naturally through the liver, kidneys and gut. The complex machinery of the liver neutralizes many toxic substances and transforms them into soluble compounds that are eliminated through the urine via the screening action of the kidneys. The gut, in turn, is responsible for removing solid waste from the body.

    As an external organ of the body, the skin has had to face numerous external hazards and threats over millions of years of evolution and adaptation to our environment. Today, the skin fulfils an excellent barrier function and few chemicals can pass through it easily.

    Many detox treatments are based on the argument that the skin is a major cleanser of the body because it secretes sebum and sweat. But sweat is little more than water, mineral salts (sodium chloride and, in smaller quantities, calcium, potassium, phosphorus and copper) and trace amounts of other elements. Saunas are one such therapy, with undeniable advantages in toning the body and stimulating circulation; however, there is no evidence that they can eliminate significant quantities of toxins, other than urea, through the skin.

    The scientific data used to support detox techniques often refer to special cases (occupational or accidental exposure to large doses of toxic substances, drugs, etc.) or isolated cases (one or very few people). The statistical evidence does not seem to clearly support detoxification.


    Detox the skin?

    In their advertisements, many detox products claim to remove the dirt and impurities accumulated in the skin each day. So, what’s new? This is precisely what soaps do, and very effectively. So let’s use soap, provided it is based on a moisturizing formula that hydrates the skin and that it respects the slightly acidic pH of the skin.

    Products that are claimed to detoxify the skin do not manage to do so effectively, for example, products containing antioxidants to combat free radicals. It is indeed true that these oxidizing radicals, sometimes essential to fight off viruses and bacteria, are potentially harmful. But since they are generated in the body as by-products of metabolism, it is difficult to combat them through the skin, as this blocks the passage of most substances. Incidentally, the intake of antioxidants in high doses can be counterproductive.

    Other products that supposedly detoxify the skin contain exfoliants to remove dead skin cells. These cells, however, far from being an undesirable impurity, defend us against viruses, which need to invade living cells to multiply. The layer of dead cells (the stratum corneum) acts as a barrier that is difficult to breach. Furthermore, healthy bacteria in the skin should not be removed, as they prevent harmful fungi and other organisms from proliferating. In short, removing the top layer of dead cells does not have a purging or detoxifying effect, as this layer is itself a natural component of the skin.

    The skin has its own excellent cleansing mechanism, as it renews itself on an ongoing basis through natural shedding, yielding a completely new skin within a few weeks. A mechanism as simple as it is effective.


    What conclusions can we draw?

    The body has effective cleansing mechanisms that have enabled us to survive to the present day. It is argued that modern civilization is more exposed than ever before to toxic substances of all kinds, but the truth is that our life expectancy continues to increase.

    The most effective cleanser for the skin, and the entire body, is to follow a balanced diet, ensure the proper functioning of the kidneys by keeping the body hydrated, do exercise, avoid unhealthy habits (such as smoking and drinking too much alcohol) that overload the liver and get enough sleep.

    Most detox treatments based on diets and other techniques make sense in cases of poisoning or drug abuse and are theoretically not harmful for healthy people. But we need to be aware that the skin has few toxins and that the idea of detoxifying the skin by applying products to it belongs more to the realm of mythology than to medical science.



    The Guardian

    The Detox Dossier

    US News Health