GroWell Cap Review: I Have Hair for the First Time in 15 Years

Jun 5, 2026 2:16 PM

I shaved my head 15 years ago and never looked back. This GroWell LED cap changed that.

From reviewing archival footage—scrolling back 63,979 or so photos on my iPhone camera roll—it appears I shaved my head for the first time sometime in the spring of 2011. I was 30 years old, and it seemed like a logical choice given the slow thinning of my always-thin hair and the pleasantly round shape of my head, the one physical trait I consistently receive compliments on from complete strangers.

It didn't feel like an especially momentous decision at the time. Looking back after 15 years of smooth-headedness, though, shaving my hair off that first time feels like a significant milestone that I galloped past without taking appropriate notice.

When you don't have hair on your head, everyone assumes you're bald. I've always been quick to correct them that I, in fact, have hair—and it's not even receding. It was, however, very thin and getting thinner. Since I was the kid whom nature denied a Vanilla Ice haircut a few short years after my mother denied me Hammer pants, my hair has always been fine and wispy. Once age thinned it enough, I just buzzed it, then kept buzzing a couple times a week for so long that no one remembered me having it.

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Well, now I have hair again, thanks to eight weeks of using an LED cap made by GroWell. I don't have a lot of hair, but I have at least as much as I did when I was 30, and maybe even as much as I did when I was 25. I wear the brand's cap for 25 minutes every other day, which is about average for these devices, and I'm using the brand's proprietary shampoo to strengthen my strands, though I'm not doing any other treatment.

How It Works

LED hair regrowth treatment is not for everyone. If the top of your head has been rendered completely smooth, it's very unlikely to make any difference. But if you have dormant follicles, they can be enlivened by the use of specific red-light wavelengths that stimulate those follicles through increased blood flow to the scalp. Results can take up to six months, but after eight weeks, the difference is noticeable enough to merit review.

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There are dozens of LED hair-growth gadgets on the market, ranging from a $50 product on AliExpress that's been shopped onto a model to comically bad effect to the $2,500 Capillus Spectrum, which boasts an aggressive array of laser diodes. Contrary to what I would have suspected, women are actually the current dominant consumer group for LED hair-regrowth therapy. As it was explained to me, women are accustomed to spending money on their appearance, and thinning hair is often experienced as a crisis. Men, on the other hand, tend to take the path I did and buzz it all off, then go about their day.

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I agreed to test the FDA-cleared GroWell, which sits in the middle of the price range at $550. It contains a total of 63 diodes, including 24 lasers and 39 LEDs. Beyond its attractive price point, comfortably between sketchy drop shippers and well-marketed products that cost nearly as much as the top-end MacBook Pro, the GroWell stands out for offering treatment at a level supported by clinical research without an overkill approach that can be counterproductive.

Also, unlike the helmet-style caps on the market, it's an insert attached to a control unit with a small 1,800 mAh Li-ion battery, which GroWell says should be good for several years of regular use. Because it's in three small pieces (a control pack that's the size of an old Motorola Razr, a USB-C cord, and a flat pad that's only as thick as a piece of cardboard), it's easy to fold up and pack on a trip. That's clutch, as you don't want to miss treatments when traveling. (Note that if you stop using the device, your follicles will return to their previous state.)

Growing Pains?

It couldn't be easier to use: Tuck the light pad inside the provided cap or one of your own, connect it via USB-C to the control module, and press the button. It will light up for the next 25 minutes while you go about your business. Because it goes in your own hat, the fit may not be perfect, and I did find myself adjusting it a bunch, which probably wouldn't happen with some of the helmet-style devices.

In a 2013 study, the levels and duration provided by GroWell with every other day of use over 16 weeks helped everyone who participated in the study regrow some hair, on average 35 percent more for men and 37 percent for women. The same study showed that using more powerful lasers for longer may actually stunt growth a bit. I'm only estimating here, but I would guess I have at least 30 percent more hair than I would have without the treatment, and maybe more.

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GroWell's therapy-grade laser and LED diodes are proprietary to Apira, the company behind iGrow and GroWell. Unlike most competitors, GowWell says to only use the product every other day, rather than every day, to give your scalp a rest day to process the cellular stimulation. Also, unlike others, they limit wattage to avoid oversaturating follicles past the optimal 3 to 4 Joules. Studies suggest that more powerful lights or more frequent use can fry your follicles and actually inhibit regrowth.

I have not yet tested other LED therapy devices to compare efficacy, but the results after two months of use with the GroWell have been dramatic. After about six weeks, a female acquaintance whom I ran into in a bar said, “I didn't know you had hair,” and then asked to touch it. Most other people seem to have come to the same conclusion—I was bald by choice, and now I'm not. Maybe that's true. Maybe, as my brother-in-law says, any problem that can be solved with money isn't a real problem. I'm not sure if that's true, but if $550 and two hours of passive treatment with no side effects can get you hair, you're really not bald.

People now ask me if I plan to keep my hair after completing my testing. I probably will. Right now, I'm still just letting my hair grow wild to see how much hair I can get. I'm only eight weeks in, and results are supposed to keep improving for up to six months. Once I have another inch or so, I'm kinda excited to go to a barber for the first time since the first Obama administration and see what he can do with it.