Baldness is no doubt something no one wants to have, whether for health or aesthetic reasons.  But with most people's luck, about 147 million people worldwide are affected by alopecia areata, an autoimmune disease causing hair loss on various parts of the body, usually on the scalp.

To address this widespread problem, researchers from the University of Wisconsin-Madison detailed in an issue of ACS Nano how they came up with a noninvasive approach.  The team has integrated an anti-baldness device into a simple hat.  Doing so, the device cannot be seen while doing its job.  And because the device is powered by the movement of the user, a battery pack or a complex electronic control system is not required.

The device uses nanogenerators-which are what they sound like, small generators-that gather energy from the movements of the user and transmit them to gentle, low-frequency electrical pulses that stimulate and reactivate dormant hair follicles.  The researchers say that the gentleness of the pulses does not even penetrate the scalp past the outermost layer.  Because of the gentle nature of the electrical stimulation, this is particularly effective in early cases of pattern baldness.  However, it can no longer help with advanced cases that are evident when the skin has already gone smooth, as University of Wisconsin-Madison materials science and engineering professor, Xudong Wang explained.  "Electric stimulations can help many different body functions," he said. "But before our work, there was no really good solution for low-profile devices that provide gentle but effective stimulations."

When the team tested their device on Sprague-Dawley rats, they found that it resulted to a higher follicle density and longer hair shaft, while comparing the results with those of conventional medical treatments.  A different set of results were from tests on genetically defective nude mice that showed how the device could improve a couple of factors that sequentially caused the increase in number of hair follicles and promoted hair regeneration.

The researchers claim that the device does not cause any side effects-a major advantage over existing medical treatment methods for baldness that cause major side effects like sexual dysfunction, depression, and anxiety.  "It's a self-activated system, very simple and easy to use.  The energy is very low so it will cause minimal side effects," said Wang.  "I think this will be a very practical solution to hair regeneration."  The team plans to execute clinical trials on humans soon.