How does infrared light support hair growth?
Photobiomodulation supports hair growth. The wavelength of light that is most effective at supporting hair growth is near infrared 830 nm.
If we look at the pharmaceuticals on the market that support hair growth, and their mechanisms of action, we can understand why 830 nm would be effective. Minoxidil was first developed as an anti-hypertensive, blood pressure regulation medication.
Scientists say that extended use of Minoxidil could result in heart complications. Unfortunately for Minoxidil to actually work you would have to keep using it for your entire life.
Another option includes a class of oral drugs known as alpha 5-reductase inhibitors. These drugs work by lowering DHT (dihydrotestosterone) systemically - meaning they lower it throughout the entire body not just in the scalp.
DHT binds to the hair follicle cutting off blood flow and thus oxygen and nutrient delivery. The hair is suffocated, begins to miniaturize, and eventually enters a dormant phase (the telogen phase) where the hair does not grow. These hairs are still alive for approximately 3 years and then undergo apoptosis (cellular death). The only way to restore the hair then is through a transplant.
While these drugs may work better than Minoxidil, in my experience, DHT is an androgen and it’s responsible for blocking the development of secondary androgenic characteristics - basically what makes a man a man - deeper voice, body hair, bigger jaw. In more simple terms these drugs have a feminizing effect on men.
In addition, a small portion of men report impotence, other sexual problems and depression that may not resolve.
To make matters worse, these drugs lower nitric oxide levels in the body. Nitric oxide is crucial for vasodilation. Nitric oxide allows your blood vessels to expand. This may be the cause of erectile dysfunction in some men.
These drugs seem to offer a choice between hair or heart.
So how does near infrared light work to support hair growth?
670 laser and 830nm non laser photons of light act on cytochrome C oxidase leading to the production of adenosine triphosphate (ATP). This is converted to cyclic AMP in the hair follicle cells, releasing energy and stimulating metabolic processes necessary for hair growth.
It releases nitric oxide from cells leading to increased vascularisation and blood flow to the scalp and distribution of nutrients and oxygen to the hair roots.
It prevents excessive build-up of DHT.
In general there is the principle "wherever energy goes blood flows"
Near infrared light draws blood to the area of application. So it reduces the DHT that's blocking the blood flow while actually increasing the blood to the specific area.
It stimulates the epidermal stem cells. The result of this is the shifting of the dormant (telogen) phase hair follicles back into growth phase hair follicles (anagen) phase. And just to remind these hair follicles can stay in dormant phase for up to three years!
But for all of this to work you need a light source that is powerful enough to pass through the hair (an effective photon blocker) and actually reach the hair follicle. This is the reason that some people try photobiomodulation with lower powered lamps for hair growth with little to no success.
The other is that they are trying to do it with an incandescent lamp and they cannot get close enough to the light source to get sufficient power density without catching their hair on fire.
And a synergy may be to combine this with a shampoo that contains ketoconazole. Ketoconazole is an antifungal that has been shown to reduce scalp DHT REF: https://onlinelibrary.wiley.com/doi/10.1111/dth.13202
Or, use of vasodilators like spearmint and menthol can increase blood flow. I like Regenepure Dr. but have no affiliation with the company. There is room for improvement and so we are undertaking to develop a gentle, high quality shampoo to compliment our skin serum. Stay tuned.
DISCLAIMER: We are not medical professionals, and this is not medical advice. Please consult your medical professional before proceeding with any protocol.