Alert on recent misleading health claim that using cosmetics makes you happier!

Laurent Misery Anthony Bewley In recent years, we have observed the emergence of a new trend in cosmetics, where some cosmetic providers (usually not the ones the dermatologists meet on a regular basis) claim that the application of their cosmetic products to the skin can have beneficial effects on client's emotions, psyche, well-being, affect, stress, sleep, mood, depression, anxiety and mental health. Certain manufacturers even claim that their products could have direct effects on brain and the nervous system. The Psychodermatology Task Force of the European Academy of Dermatology and Venereology (EADV) has alerted authorities, consumers and health care professionals about to this worrying trend and misleading marketing.1 We know that the study of the relationship between the skin and the nervous system, or between the skin and the mind, is a fascinating and rapidly expanding field of research. It is well evidenced that the psychological impact of skin disorders can be very significant, and that stress can aggravate cutaneous disorders.2 We also know that the interaction between the skin and the nervous system is very robust, and that skin properties (sweating, blood flow, inflammation) can be modified by the nervous system and the brain.3 There is evidence that the use of cosmetics can potentially improve the quality of life of users to some extent, particularly in the case of skin diseases. Cosmetics have been used to ‘enhance’ or alter appearances since ancient times (e.g. eyeliner in ancient Egypt). And evidence has shown that, where patients or clients choose to use an agent which makes a visible difference, this may have an effect on quality of life and well-being. Certainly, we and others are actively engaged in appearance-related and psychodermatological research. Genuine neurocosmetics are supposed to modulate the functioning of the neuro-immuno-cutaneous system only at the epidermal level because they are cosmetics,4 and have been traded since the 1990s. They are frequently used for their soothing effect, especially in the case of sensitive skin and sometimes in patients with atopic dermatitis or other inflammatory dermatoses. However, so-called ‘new neurocosmetics’ are different and are marketed as the fruit of the latest industry-sponsored discoveries and are supposed to transform consumers' lives. Some manufacturers claim that these effects are directly linked to the sensory properties of their products on the skin, but the evidence is based on non-comparative studies on emotions and well-being or multisensory evaluations.5 These approaches in neuromarketing and consumer neuroscience are not aligned with the rigorous scientific and clinical principles of dermatology, psychodermatology, health psychology, psychiatry or skin neurobiology. While food and clothing also produce pleasant sensations, we do not classify them as ‘neuro-foods’ or ‘neuro-clothing’. The products are pleasant cosmetics, but not neuro-cosmetics, and they do not represent a novel scientific advance. More worryingly, some pseudo-neurocosmetics contain agonists and antagonists of neurotransmitters like substance P, norepinephrine, serotonin, dopamine, cannabinoids or opioids, with the aim of exerting psychotropic effects through their transmission to the central nervous system via the blood flow (direct effect) or via neuronal processing from the skin to the brain (indirect effect). We have to underline that all these neuronal pathways are deeply involved in addiction mechanisms.6 As dermatologists, psychiatrists or psychologists, we are concerned because these pseudo-neurocosmetics, which are commonly very expensive, may appeal specifically to a vulnerable population with self-confidence issues or psychiatric disorders. Because psychiatric comorbidities are very frequent in patients with skin diseases, dermatologists should be at the forefront of advocating for their patients and combating these scientifically unsupported claims. In conclusion, it is important to acknowledge the evidence that cosmetics can only have an effect on the skin, mucous membranes or skin appendages. There is no convincing evidence that a cosmetic can have a direct effect on the brain and the psyche. If this were the case, the use of the product would have psychotropic implications associated with a risk of inducing dependency, and such products would be not cosmetics but medications or drugs (Figure 1). Claims of the direct psycho-neurological benefits of ‘neuro-cosmetics’ should be considered as misleading, and we, as client or patient advocates, have a duty to point out the implications and consequences of such marketing. None. None. Not applicable. Not applicable. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.