Can red light diminish wrinkles?

Can infrared phototherapy alleviate signs of ageing?

It is entirely natural to see wrinkles form as time goes by. The appearance of these small furrows is due to a combination of genetic, hormonal, and environmental factors. Among the intrinsic processes, we can mention the gradual decrease in the synthesis of collagen and elastin, the dermal proteins ensuring the tone and elasticity of the skin, initiated from the age of 25, as well as the slowing down of cellular regeneration, estimated at 50% between the ages of 30 and 70, leading to a thinning of the skin barrier. In addition to these internal factors, sun exposure throughout life plays a key role in the appearance of wrinkles. Referred to as photoaging, this process accounts for nearly 80% of skin ageing. Finally, the facial expressions we adopt, which reflect our emotions, accelerate the onset of wrinkles.

While some individuals are quite comfortable with their wrinkles and fine lines, the emergence of these ageing signs can be distressing for others who then seek solutions. In recent years, a new method has gained popularity in combating skin sagging: the red and/or infrared light therapy. Indeed, this technique has its appeal: it can be performed at home, provided one invests in an LED mask, it is non-invasive, and it is associated with few side effects. Moreover, several studies have shown that it has interesting biological effects in reducing wrinkles.

Infrared light is primarily associated with a stimulation of fibroblast activity, the dermal cells that produce collagen and elastin. More specifically, infrared light activates cytochrome c oxidase, a complex protein unit IV of the mitochondrial transport chain, responsible for the synthesis of adenosine triphosphate. Adenosine triphosphate, or ATP, is a key molecule in cellular energy. This interaction enhances cellular activity, oxygen consumption, gene expression, growth factors, and cell proliferation.

This was particularly demonstrated during a study in vitro conducted by PARSA and his team in 2021. Human fibroblasts were irradiated daily with a combination of red LED lights (640 nm) and near IR (830 nm) at 0.5 mW/cm2 for 10 minutes (0.3 J/cm2). After three days, the researchers observed a significant increase in the expression of the ELN, COL1A1 and COL3A1 genes, which code for elastin, type I collagen and type III collagen, respectively, as well as the synthesis of type I procollagen and elastin proteins. ATP production also increased.

By stimulating the production of collagen and elastin and enhancing cellular regeneration, the infrared light establishes itself as a non-invasive solution to improve skin firmness.

Infrared light and wrinkles: what is the clinical evidence?

While red light cannot erase wrinkles as such, it can reduce their visibility and help the skin regain suppleness and elasticity. Studies on this subject have multiplied in recent years, in parallel with the rise of home-use LED masks. Some of these are presented in the table below.

Study	Light Parameters	Protocol	Results
LEE et al. (2006)	Near-infrared red light (λ=900 nm and I=35 mW/cm2)	Daily exposure of 20 volunteers for a duration of 6 months, 15 minutes each day	75% of participants reported an improvement in their skin texture
MATUSCHKA & al. (2014)	Red to near-infrared light (λ=570–850 nm and I=23.4 mW/cm2)	Exposure of 57 volunteers twice a week for 6 months, each session lasting 30 minutes	69% of participants reported a reduction in their wrinkles
SIRITHANABADEEKUL & al. (2023)	Red light (λ=633 nm and I=32.64 mW/cm2)	Exposure of 20 volunteers twice a week for 6 weeks, each session lasting 12 minutes	Average reduction of 9.38% in neck wrinkles
GRANOTIER & al. (2023)	Red light (λ=630 nm and I=21.7 mW/cm2)	Exposure of 20 volunteers twice a week for 3 months for 12 minutes each session	Average reduction of 38.3% in crow's feet wrinkles

The benefits of red or infrared light for reducing wrinkles (λ = wavelength and I = irradiance).

Effets de la lumière rouge (λ = 630 nm et I = 21,7 mW/cm2) sur les rides pattes d'oie. — Effects of red light (λ = 630 nm and I = 21.7 mW/cm2) on crow's feet wrinkles.
Source: GRANOTIER F. & al. Reversing signs of skin ageing through red light photobiomodulation. Skin Research and Technology (2023).

If the red or infrared light is beneficial for reducing wrinkles, it is crucial to consider certain usage precautions.

Indeed, to safely benefit from infrared phototherapy, it is essential to always follow the manufacturer's instructions, particularly regarding exposure time and frequency of use. Furthermore, it should be noted that these devices are not suitable for everyone and should not be used by pregnant or breastfeeding women, as a precautionary principle, nor by individuals undergoing photosensitising treatment, those with coagulation disorders, skin cancer, or suffering from an active phase of inflammatory dermatosis.