Red light therapy has come a long way since then. Rahman explained that red light wavelengths activate the mitochondria in skin cells and increase blood flow to hair follicles. This uptick in stimulation encourages mitochondria to increase their production of adenosine triphosphate (ATP), which promotes new growth.

When it comes to efficacy, we noted that iRestore Elite is FDA-cleared. This is a designation bestowed on moderate-risk tools that are sufficiently similar to other cleared devices already on the market. There are specific pathways that devices must follow to obtain FDA clearance, and the iRestore Elite was cleared through the FDA’s 510(k) premarket evaluation.

There are three hair-growth devices in iRestore’s lineup: the entry-level Essential ($499), the mid-tier Professional ($899), and the Elite ($1,899). Each contains iRestore’s “Lumitech” technology, which combines LED lights and medical-grade lasers. These laser diodes are proprietary to iRestore and are called Vixo lasers, operating in the 655- to 680-nanometer (nm) range. (Preliminary studies with mice have shown that using red light in the 600- to 660-nm range, and infrared wavelengths in the 800- to 850-nm range, can promote everything from cell regeneration to pain relief.)

The idea is that this dynamic duo can penetrate deeper into the skin than ordinary red light with lasers, while the LEDs ensure light is distributed across the scalp for maximum efficacy. Together, they reach a maximum of 2,500 milliwatts (mW), compared to the Professional’s 1,410 mW and Essential’s 600 mW.

The Elite is iRestore’s top-of-the-line offering and has the most LEDs of the three laser hair-growth systems, with 500 diodes total—that’s 300 lasers and 200 LEDs. The Essential has 51 lasers and 69 LEDs for a total of 120 diodes, while the iRestore Pro has 82 lasers and 200 LEDs for a total of 282 diodes. The Elite was also designed to cover more of the scalp. The Elite requires 12 minutes of daily use, while the Professional and Essential require 25 minutes every other day.

If price is not an object, the Elite is the no-brainer choice for more concentrated light therapy, shorter use time, and potentially faster results.

Rooting for You

Photograph: Julia Forbes

The helmet arrived in hefty red packaging, containing the helmet, portable battery pack, charging cord, and a red-and-black zippered travel case. It feels very fragile, and I wouldn’t throw it around—then again, you probably wouldn’t be shoving an $1,899 helmet in the back of your bathroom vanity.