Common misconception: blue light emitted by screens contributes to skin ageing to the same extent as sunlight.

Over the past decades, the ubiquity of digital devices has profoundly altered our luminous environment. Smartphones, computers, tablets or televisions are now part of everyday life and entail repeated exposure to blue light, primarily emitted by light-emitting diodes (LEDs) and fluorescent lighting. Unlike natural exposures, this light is perceived at close range, often for prolonged periods, especially around the face.

The blue light corresponds to a portion of the visible spectrum between 400 and 500 nm.

Although the sun remains by far the primary source of blue light to which we are exposed, digital screens also emit it, albeit in proportions lower than solar radiation. However, the frequency and proximity of this exposure raise increasing questions about its biological effects on the skin.

According to several recent studies, prolonged and repeated exposure to blue light could disrupt certain functions of skin cells, prompting questions about its potential role in premature skin ageing.

Several studies suggest that the blue light emitted by screens is capable of inducing a oxidative stress at the cutaneous level. AUSTIN and his team notably demonstrated that just one hour of exposure to light generated by electronic devices at very close proximity was sufficient to significantly increase the production of reactive oxygen species in human fibroblasts. These findings underscore that even a brief exposure can trigger harmful cellular responses, although the effects of repeated or chronic exposures remain poorly characterised.

Conversely, the connection between oxidative stress and skin ageing is well established.

The skin is one of the main target tissues of free radicals, which play an important role in its ageing. With age, not only does the production of free radicals increase, but the DNA repair capabilities of skin cells gradually decline. This accumulation of oxidative damage promotes fibroblast impairment, degradation of the extracellular matrix and, ultimately, the appearance of wrinkles and skin laxity.

At the molecular level, blue light primarily induces the formation of superoxide (O₂⁻), a highly reactive free radical generated notably through the activation of flavins. This radical is then rapidly converted to hydrogen peroxide, contributing to a diffuse yet sustained oxidative stress. Unlike acute UV exposures, blue light may exert its deleterious effects through a continuous production of low levels of reactive oxygen species, capable of evading antioxidant defences and inducing cumulative DNA damage.

Moreover, the excessive generation of free radicals induced by blue light is accompanied by a activation of inflammatory pathways. Studies have demonstrated an increase in pro-inflammatory cytokines, such as TNF-α, via the activation of the AP-1 and NF-κB transcription factors. This inflammatory response contributes to the impairment of the skin barrier and fosters an environment conducive to premature ageing. It should also be noted that blue light stimulates the expression of matrix metalloproteinases, enzymes involved in the degradation of the collagen and elastin. These enzymes not only break down existing fibres but also inhibit the synthesis of new collagen, compromising the skin’s repair mechanisms and promoting long-term loss of firmness.

Beyond structural ageing, blue light could also influence skin pigmentation.

Multiple lines of evidence suggest it can induce persistent hyperpigmentation, notably in skin phototypes with darker skin. This response appears to be linked to a disruption of melanocyte activity, with an increase in melanogenesis. This phenomenon can be partly explained by a greater expression of the tyrosinase–dopachrome tautomerase complex in the melanocytes of darker skin, making these cells more reactive to blue light. The oxidation of melanogenic precursors, together with diminished carotenoids, potent natural antioxidants, would favour more intense pigmentation, potentially manifesting as pigmentary spots.

Finally, some studies suggest that blue light could interfere with the cutaneous circadian clock.

A decrease in PER1 gene expression was notably observed in keratinocytes exposed to 410 nm blue light. This disruption of biological rhythms could impair the nocturnal phases of skin repair and regeneration, thereby indirectly accentuating the mechanisms of cutaneous ageing.

In practice, it is important to distinguish the natural blue light of the sun from that emitted by digital screens.

The sun remains by far the principal source of blue light to which the skin is exposed, and above all the only one associated with ultraviolet radiation, whose deleterious effects on skin cells and skin ageing are clearly established. In contrast, artificial blue light from screens is emitted at far lower intensities and falls within a broader light spectrum, which limits its biological impact.

To date, available data suggest that blue light from screens can induce measurable cellular responses in vitro, notably in terms of oxidative stress or pigmentation disturbances. However, clinical evidence demonstrating that daily screen exposure significantly accelerates skin ageing remains insufficient. The observed effects appear to depend mainly on specific experimental conditions, which are difficult to translate to real-world exposure in everyday life.

Thus, while blue light emitted by screens constitutes a legitimate subject of research, it should not be placed at the same level of risk as solar exposure.

Note : In practice, prolonged screen use is more commonly associated with ocular fatigue, hence the emergence of blue-light filtering glasses.

• MORTAZAVI S. A. R. & al. Can light emitted from smartphone screens and taking selfies cause premature aging and wrinkles? Journal of Biomedical Physics and Engineering (2018).

• Scientific Committee on Health, Environmental and Emerging Risks SCHEER. Opinion on potential risks to human health of light emitting diodes LEDs (2018).

• AUSTIN E. & al. Electronic device generated light increases reactive oxygen species in human fibroblasts. Lasers in Surgery and Medicine (2018).

• GOLDUST M. & al. The impact of blue light and digital screens on the skin. Journal of Cosmetic Dermatology (2023).

• WHEELWRIGHT T. Cell phone usage stats 2026. Reviews.org (2025).

• RAMIREZ S. Smartphone statistics 2026: Global usage, market trends & insights. SQ Magazin (2025).