Capillus is a tech startup with an interesting premise: that waves of infrared light emitted inside of a hat can regrow hair in only 6 minutes a day. Their products are quite expensive, so consumers are eager to know whether their products are actually based on good science.
In this article we’ll review the formulation of Capillus and the wavelengths of infrared light used based on medical research to determine whether we believe the hats can truly regrow hair or are a waste of (a lot of) money.
Can Red Light Therapy Regrow Hair?
Before we can specifically evaluate the Capillus device, we must evaluate the broader premise: whether red light therapy can regrow hair in general. As we detailed in our recent infrared sauna review, low level light therapy (LLLT) has been proven in medical research to have a host of health benefits, mostly related to its mediation of inflammation.
Since hair loss in the context of pattern baldness has been shown in medical studies to be an inflammatory process, this suggests red light therapy could be a useful treatment.
There have been studies directly testing red light therapy on hair loss.
A 2013 clinical trial published in the Lasers in Surgery and Medicine journal found that red light therapy at a wavelength of 655 nanometers (nm) “significantly improved” hair counts in men with pattern baldness compared to a control group using incandescent red light.
There was a followup trial published in the same journal the following year, this time testing the effects of LLLT on women with pattern baldness. The study found similar benefit in women as the previous study found in men; hair counts were significantly increased.
A more recent medical review of red light therapy for hair loss suggested that the therapy may be more beneficial for women because pattern baldness is driven by steroid hormones (androgens). Women have less of these hormones than men, and thus the therapy isn’t “constantly fighting against the influence of DHT” as it is in men. The researchers suggested this is why red light therapy trials for hair loss have been slightly more favorable in female populations than male.
Overall we can conclude that there is preliminary evidence suggesting that red light therapy may be effective for hair loss.
Can Capillus Regrow Hair?
Just because red light therapy may be effective for hair loss doesn’t necessarily mean the Capillus will, if it’s not built in a way that mirrors red light devices used in the medical trials.
There are several factors to consider in regards to red light devices and hair. Two of the most important are wavelength (of the red light), and irradiance. Wavelength measures the frequency of the light, and irradiance measures the power.
Capillus has three products: CapillusOne, CapillusPlus and CapillusPro.
Both CapillusOne and CapillusPro use a wavelength of 650 nm, and we can’t find the wavelength listed for CapillusPlus but it’s likely the same. This appears to be an effective wavelength, as it’s within the range of the above-linked medical studies.
The power reading (mW) for the Capillus lasers is 5, which is the same as that used in the medical studies above.
Another medical review of red light for hair loss concluded that “low-level light...at low powers of 5 mW, can enhance hair growth”.
It appears that the specs used by Capillus are grounded in good science.
There have been no studies on the Capillus device itself, so we can’t definitively say it’s proven to work.
Overall we believe the Capillus may be effective for hair loss in both men and women, based on its specs, but there are some limitations that are worth discussing.
First, there seems to be no medical consensus yet on the best overall irradiance for hair loss. The lasers being of the same power is just one factor; we need a consensus on how long to use the lasers and how many lasers to use to get research-backed recommendations for overall power, and we believe the research is too early-stage to determine that.
To illustrate this point, consider one hat with 30 lasers and one hat with 60. The lasers may be of the same power, but the person using the hat with 60 lasers would receive more overall irradiance.
Perhaps the person using the 30 laser hat wears the hat for 5 times as long daily as the person wearing the 60 laser hat though. Then the wearer of the 30 laser hat would be receiving more irradiance daily. We don’t know what the best practices are yet in this regard.
We believe that at the current stage of the technology, the Capillus may be helpful for hair loss, but we don’t believe that it’s likely to fully reverse moderate-to-severe hair loss. There isn’t really any medical research backing the idea that a man with severe hair loss can use a LLLT device and restore his hairline to its youthful state.
Since these products seem relatively safe and free of side effects, they may be worth trying for patients with mild hair loss whose doctors approve of the treatment.
Misleading Health Claims
We disagree with several of the health claims on the Capillus website.
First, the company claims “clinically proven technology.” While red light therapy has been proven in clinical trials to be effective for hair loss, the Capillus device has not. Thus we find it to be irresponsible and misleading for the company to make this statement.
Second, we find the “6 mins a day” recommendation made by Capillus to be unscientific, based on the lack of scientific consensus on optimal total irradiation for hair loss as we discussed in the previous section. Capillus doesn’t source this recommendation, so we will assume it’s just a marketing claim and not backed by any clear scientific evidence.