Finding that first grey hair or two in your otherwise dark locks comes as a bit of a shock for most people, as going grey is one of the earliest signs of aging. Once the greying process has begun, the transition to all or mostly grey hair is only a matter of time, unless of course you choose to cover your grey with hair dye, as do nearly 88 percent of American women as well as a lesser percentage of men.
Everyone knows that “aging” causes grey hair but what is the real underlying biological reason behind this phenomenon? And is going grey really inevitable as you age? What if grey hair could be reversed naturally without covering it up with hair coloring?
First of all, let’s get a closer look at just why hair turns grey as you age. The age at when a person begins to go grey varies among individuals depending on genetic and other factors, but usually begins for most people in their third decade of life and then progresses until the majority of their hair shafts are affected. To better understand how this happens, let’s examine the anatomy of a human hair.
Human Hair Anatomy
The hair shaft, the part that you see and can run your comb or brush through, is non-living and is made up of three layers of a type of protein called keratin. The inner layer is called the medulla and may or may not be present, depending on the type of hair you have. The middle layer is called the cortex and makes up the bulk of the hair shaft. The medulla and the cortex both contain cells that hold pigment that give your hair its colour. The outermost layer is called the cuticle, which under magnification looks like overlapping roof shingles tightly packed together. Most hair conditioners are formulated to smooth out this outer keratin layer.
Back to the hair pigment cells in the middle and innermost hair layers. These pigment cells are called melanosomes (say “me-LAN-oh-somes”) and are loaded with melanin, a natural pigment found in skin, hair and eye colour. The type of melanin you have determines your hair colour. People with black or brown hair have a type of melanin called eumelanin and people with red hair have a different pigment called pheomelanin.
These melanosomes loaded with pigment are transported to the hair shafts by cells called melanocytes (say “me-LAN-oh-sites”) which are located in the hair follicles. These follicles are the living part of your hair and are embedded at the base of each hair shaft just under the skin of your scalp.
The follicles also serve as an “anchor” for each hair and at the base of each follicle is the hair bulb, the place where living cells grow and divide to form the actual hair shaft. The hair bulb is also the place where the melanocytes (the pigment cells) reside. The cellular precursors to the melanocytes are melanocyte stem cells which also reside in the follicular bulb and provide a reservoir for the continuous production of melanocytes. As long as this continues uninterrupted, the melanocytes continue to produce pigment and your hair retains its natural colour.
Why Hair Turns Grey
The greying of hair due to aging involves several processes, including the depletion of the melanocyte stem cells, changes in neurohormones, and oxidative stress, but it’s oxidative stress that is thought to be the main driver of greying hair. In a nutshell, oxidative stress results because your body produces chemical compounds called free radicals as a by-product of your metabolism. These free radicals can be very damaging if left unchecked as they produce inflammation.
Fortunately, your cells also produce compounds known as antioxidants which serve to neutralize the free radicals and keep your body in balance. This process of oxidative stress builds naturally over time and has been implicated in the development of chronic diseases such as diabetes, heart disease and even cancer.
Psychological stress has also long been thought to have an effect on the greying of hair as well. The process is well documented in mice but has not been conclusively shown in humans. This is not because scientists don’t think there is a relationship, but it’s a difficult thing to measure. Of course there are many anecdotal reports of a person’s hair turning white practically overnight as the result of an acute psychological shock.
In a rather remarkable study on human hair greying process the authors found that at times not only does greying of individual hair shafts naturally reverse itself without any intervention but that greying is conclusively tied to periods of increased life stress in humans.
They also point out that within white hairs, there are specific components of mitochondrial energy metabolism that are upregulated. Mitochondria (say “my-toe-CON-dree-ah”) are tiny organelles within the cells that produce the energy necessary for the cells to function. This suggests that metabolism regulates not only hair growth, which has been well demonstrated, but hair pigmentation as well.
Energy metabolism is known to be a major contributor to other features of aging which are disease related. The authors also state that with exercise and dietary interventions, cellular markers of aging have been demonstrated to be temporarily reversible and their data supports that "aging is not a linear and irreversible biological process and may, at least in part, be halted or even reversed".
Addressing The Grey Hair Problem
Because greying hair seems to be produced by multiple pathways, including metabolic factors, neuroendocrine alterations, oxidative stress and life stressors, all of which have been implicated in the aging process, it makes sense to address it in the same way. A healthy nutritious diet high in antioxidant rich fruits and vegetables, regular exercise, adequate sleep and stress reduction are all common sense additions to your routine. In addition, supplementing your NAD+ levels, which has been clearly shown to have a wide variety of powerful anti-aging effects, including the promotion of brain health and cellular regeneration as well as decreased inflammation, can directly address the energy metabolism component of greying hair.
NAD+ (Nicotinamide Adenine Dinucleotide) is essential for cellular functioning and repair and levels of NAD+ naturally decline as you age. This decline contributes to many of the unwanted changes you are likely to experience as you grow older, including cognitive decline, lessening muscle strength and a reduction in bone density.
Supplementation with a high quality NAD+ product is the most reliable, practical and effective way to increase your levels. You can find more information on all of our NAD+ supplements here, including NAD+ as well as its precursor NMN. Daily NAD+ supplementation will increase your levels of this powerful coenzyme and ensure you have the very best protection against the damaging effects of the aging process. And who knows, perhaps you’ll be able to throw away that hair dye!
References:
- Itou T, Ito S, Wakamatsu K. Effects of Aging on Hair Color, Melanosome Morphology, and Melanin Composition in Japanese Females. Int J Mol Sci. 2019;20(15):3739. Published 2019 Jul 31. doi:10.3390/ijms20153739
- Nishimura EK. Melanocyte stem cells: a melanocyte reservoir in hair follicles for hair and skin pigmentation. Pigment Cell Melanoma Res. 2011;24(3):401‐410. doi:10.1111/j.1755-148X.2011.00855.x
- Nahm, M., Navarini, A. A. & Kelly, E. W. Canities subita: a reappraisal of evidence based on 196 case reports published in the medical literature. Int J Trichology 5, 63–68,doi:10.4103/0974-7753.122959 (2013).
- Zhang, B. et al. Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells. Nature 577, 676–681,doi:10.1038/s41586-020-1935-3 (2020).
- Rosenberg A, Rausser S, Ren J et al. Human Hair Graying is Naturally Reversible and Linked to Stress. bioRxiv 2020.05.18.101964; doi: https://doi.org/10.1101/2020.05.18.101964
- Kiss T, Giles C, Tarantini S. et al. Nicotinamide mononucleotide (NMN) supplementation promotes anti‐aging miRNA expression profile in the aorta of aged mice, predicting epigenetic rejuvenation and anti‐atherogenic effects. FASEB Journal 18 April 2020 https://doi.org/10.1096/fasebj.2020.34.s1.04769
