South Korean scientists have developed a flexible light-therapy cap that could become a new tool for combating hair loss. In laboratory experiments, the device suppressed age-related changes in hair follicle cells by nearly 92% compared with untreated samples, according to a study published in Nature Communications (NatCom).

The technology was created by researchers at the Korea Advanced Institute of Science and Technology (KAIST) with support from City University of Hong Kong. The cap is based on organic light-emitting diodes (OLEDs) that emit near-infrared light in the 730–740 nanometer range. According to the authors, this wavelength is optimal for activating dermal papilla cells — key structures at the base of hair follicles responsible for hair growth.

“Because OLED panels are thin and flexible, they can closely conform to the curved surface of the scalp, providing uniform light stimulation across the entire area,” explained electrical engineer Ken Cheol Choi of KAIST.

Unlike existing light-therapy “helmets,” which rely on lasers or conventional LEDs and often have bulky designs, the new system is integrated into a soft, flexible cap. This allows more even light distribution and may improve treatment effectiveness.

In laboratory conditions, researchers evaluated the radiation’s effect on human dermal papilla cells, which with age begin producing a marker of cellular aging — β-galactosidase. Exposure to infrared light significantly reduced levels of this enzyme by 92% compared with the control group. The effect was notably stronger than that achieved with red light, which is commonly used in current devices.

“We plan to further confirm the safety and effectiveness of the technology in preclinical studies and gradually assess its therapeutic potential,” Choi noted. Developers are also working on a version of the cap that can be fully washable for everyday use.

Currently, only a few approved treatments for hair loss are available: minoxidil can slow hair loss but does not work for everyone, while finasteride may be effective but carries a risk of side effects and is not prescribed for women. As a result, interest in low-intensity light therapy continues to grow.