Safety Razors Demonstrate Lower Incidence of Erythema, Multispectral Near-Infrared Spectroscopy Finds

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Researchers involved in a study published in Skin Research and Technology utilized multispectral near-infrared spectroscopy (NIRS) to quantify and qualify the effects of safety razors versus cartridge razors. As a result, they found that safety razors exhibited a lower incidence of erythema than cartridge razors.

The observational study enrolled 59 healthy male volunteers. All patients were adults above the age of 18, proficient in English, and did not exhibit signs of a skin condition in the relevant area that may lead to or be accompanied by skin redness.

Two widely available razors in the Canadian market, a safety razor (Razor A) and a 3-blade cartridge razor (Razor B), were assessed. Shaving-induced erythema was meticulously assessed immediately post-shaving, at 5 minutes, and at 10 minutes.

The utilization of multispectral NIRS, facilitated by the MIMOSA Pro imaging device, allowed for the non-invasive examination of tissue layers, unveiling changes in composition, oxygenation, and blood flow.

The safety razor, characterized by a single blade, induced significantly less erythema than its multi-blade counterpart. The immediacy of the impact was apparent, with 40.3% of the safety razor-shaved skin displaying erythema compared to 57.6% with the cartridge razor. Even at 5 minutes post-shaving, the difference persisted, with 36.5% versus 53.8% erythema incidence, respectively.

The results of the study suggest that the design difference attributable to safety razors, such as controlled razor chatter and gentler gliding, contribute to the observed lower incidence of erythema, according to researchers. The delayed erythema onset prompted a reflection on microtrauma and nicks from shaving among researchers, who discussed the balance needed for effective hair removal with minimal skin injuries.

"The study has showcased multispectral NIRS imaging as a valuable tool for assessing and quantifying shaving-induced erythema and revealed significant differences in shaving-induced erythema between safety and cartridge razors," according to study authors Boodoo et al. "The lower incidence of erythema associated with safety razors suggests a potential advantage for individuals prone to skin irritation. However, it is important to note that the complex mechanisms and individual factors contributing to shaving-induced erythema warrant further investigation."

Reference

Boodoo C, Duta D, Swift N, et al. Multispectral near-infrared spectroscopy study evaluating the effect of razor design on shaving-induced erythema. Skin Res Technol. January 26, 2024. Accessed February 1, 2024. https://doi.org/10.1111/srt.13598