It’s similar to how red-light face masks work. These masks are usually worn for about 10 minutes and always have a light wavelength level in the 600-nm range (usually 630 to 660), like the HigherDose hat does, but you’ll also see masks with higher infrared-light levels that promise healing and reduced inflammation. The hat delivers only the main red-light therapy level and features 120 medical-grade LED bulbs arranged in a half circle for easy wear around your head.

The technology is FDA-cleared, meaning the FDA has determined that this device is substantially equivalent to an existing legally marketed device. HigherDose specifically states that the hat uses “FDA-cleared technology known to stimulate hair growth and improve scalp health,” but this is not the same as FDA-approved, which goes under much more rigorous testing. FDA-cleared is the only status we’ve really seen with red-light devices, though, and it’s the same status you’ll see on our red-light mask recommendations.

Photograph: Nena Farrell

It’s fun that the HigherDose hat really does look like an actual hat. There are other devices we’re testing that look straight off a Star Wars X-Wing, but I could easily wear the HigherDose hat out in public and get zero looks or questions. You can barely tell it’s lit up while I’m wearing it; the only giveaway is the small battery pack on the back of the hat. You can also remove the battery pack easily if you want to wear the hat without any tip-off that it’s a gadget. There’s an adjustment strap in the back and even a cutout that I could put a ponytail through while the battery pack is attached. It’s a legitimate baseball cap that hides 120 light bulbs inside.

Using this hat also reminded me of using an infrared brush. Infrared brushes lock in moisture, so some days that I wore this hat, my hair felt a little oily afterward (usually because I was procrastinating on wash day). I usually tried to wear this hat before taking a shower, since it would lock in more moisture, and my hair leans on the oily side at the roots. However, depending on your hair texture and oil level, this may not come up.

Growth Chart

Photograph: Nena Farrell

I took a quick, crappy picture my first week of using the HigherDose hat. You can see a scraggly regrowth section in my part line, along with a healing scab that was a clear irritation spot that targeted my compulsion to pull. That photo is from September. Compared to photos I took in January, you can easily see a difference. Thicker roots, fewer patches, and a troublesome short patch had grown in nicely in my weeks wearing the hat. My scalp looks better, and the overall texture of my hair looks smoother.