In recent years, the cosmetics industry has commercialized many products that are supposed to fight against the harmful effects of exposure to blue light from screens on the skin. Adverse effects that remain to be proven scientifically, proof that this is rather a commercial opportunity.
Previous studies have pointed to the potentially damaging health effects of prolonged exposure to blue light. Scientists have already shown that this blue light can disrupt sleep and promote myopia, especially among young people. Last July, an American study showed that it attacks the retina eyes that can blind, especially the youngest.
Blue screens flood our daily lives
"In our modern societies, we are really flooded with blue light, for an average of 6 hours per day in France," says Catherine Grillon, a researcher in skin biology at a CNRS laboratory in Orléans. Smartphone, tablet, e-reader, computer screen ... the sources of blue light have invaded our daily lives.
An important and chronic exposure "can be deleterious" also for the skin, causing an "oxidative stress" contributing to skin aging, admits the researcher. However, in small doses, blue light is not harmful: it is even used as a therapy against skin diseases such as acne, eczema or psoriasis, or even certain dental diseases.
A flourishing business
In recent years, cosmetics players have seized the commercial opportunity of combating the harmful effects on the skin of exposure to blue light. Many SMEs have become involved in this new business while large groups have not yet shown strong interest.
However, when the Uriage laboratory started digging the question in 2014, "there was really very little" on the subject in the scientific literature, recalls Luc Lefeuvre, director of research and development of the company.
Scientific reality or commercial opportunity?
It is questionable whether this business opportunity is based on real scientific evidence. "Certainly on skin models, as we want to see differences and the action of our products, we maximize the dose so as to trigger an effect on the skin," says the researcher. "I know that my product is effective against blue light, but I still have trouble correlating the exposure of my model and the reality," he says.
To go further, "it would be necessary to put oneself in real conditions of life." But as it is a radiation much less aggressive than the ultraviolet rays, the impact of the blue light will appear perhaps after a few months, some years, or much later, "adds Luc Lefeuvre.
The discovery of a scientific proof looks difficult
Some providers of cosmetic assets have started clinical trials to obtain concrete answers. Again, they are limited since they only cover a dozen volunteers addicted to screens and are only followed for a few weeks. "As UV is not far from the blue light in the wavelength spectrum, it is not necessarily obvious to differentiate" their respective effects on the skin, notes Catherine Grillon CNRS.
"There is a marketing effect, that's for sure, like any other pretext for selling a cream," confirms the researcher. Tatsu Kurebe, a Japanese entrepreneur in the cosmetics industry, confirms this trend. "In Japan, some companies also market anti-blue light products, but this is not a hot topic, there is no evidence to support" their claims, he sweeps.