The Theory of Oxidative Stress: Free Radicals Turn Hair Gray

(Part 1 of a two Part Review of Oxidative Stress Theory For Grey Hair) Let’s deal with it: 2011 is the year of the free radicals. From skincare systems encouraging us to shield ourselves from unsafe free radicals to diets meant to purge us from these cell-damaging entities, it appears as though our society is continually on the defensive in opposition to free radicals. Even so, free radicals aren’t just responsible for unhealthy diets and tired-looking skin: they’re also directly behind the silver hair strands that are sprouting on your head. From Wikipedia:

The free-radical theory of aging (FRTA) states that organisms age because cells accumulate free radical damage over time. A free radical is any atom or molecule that has a single unpaired electron in an outer shell. While a few free radicals such as melanin are not chemically reactive, most biologically-relevant free radicals are highly reactive. For most biological structures, free radical damage is closely associated with oxidative damage. Antioxidants are reducing agents, and limit oxidative damage to biological structures by passivating free radicals. Strictly speaking, the free radical theory is only concerned with free radicals such as superoxide ( O2- ), but it has since been expanded to encompass oxidative damage from reactive oxygen species such as H2O2, or OH-.

Underneath those gray hairs lies a battle that our bodies wage every single day. On the one hand, we have our antioxidants (comprised of vitamins, proteins and enzymes), which protect our body against cellular deterioration. On the other hand, we have pro-oxidants (or free radicals), which make up a typical component of contemporary living. From pollution and smoking to deficient diets plus a lack of exercise, a build-up of those pro-oxidants end in an imbalance inside the body, otherwise known as oxidative stress.[ C. E. CROSS, B. HALLIWELL, E. T. BORISH, W. A. PRYOR, B. N. AMES, R. L. SAUL, J. M. McCORD, and D. HARMAN. “Oxygen Radicals and Human Disease.” Ann Intern Med, October 1, 1987; 107(4): 526 - 545.] As far as your graying hair is involved, oxidative stress can wreak havoc on your capacity to restore your locks to their original coloration and luster. So how does oxidative stress cause hair follicles to go gray? Each tiny follicle on your head is involved in a dynamic hair growth cycle, during which the follicle is either in an extended interval of expansion (the anagen stage), in a period of rest (the telogen stage) or in a transitional interval in between both (the catagen stage). The anagen stage is by far the most active part of the hair growth routine, and can be divided into half-dozen distinct pieces. For the purpose of gray hair and oxidative stress theory, we’ll give attention to anagen stage III and anagen stage IV. Hair follicle melanocytes (specialized cells which directly manage the pigment of one's hair) achieve their peak of development for the duration of anagen stage III. As the melanocytes proliferate, they become aligned inside the foundation of the hair follicle bulb - also often known as the papilla cavity – and start the transition to anagen stage IV, which marks the hair pigmentation process. Based on biomedical and pathology researchers within the UK, US and Germany, oxidative stress directly impacts melanocyte development through the anagen stage III process. An excess of pro-oxidants accumulation inside the papilla cavity and overwhelm the melanocytes, as a result killing off these specialized cells. As the hair follicle transition into anagen stage IV, there are no longer any melanocytes to pigment the hair, resulting in the gray hair strand. [TOBIN DJ, SLOMINSKI A, BOTCHKAREV V et all (1999). “The Fate of Hair Follicle Melanocytes During the Hair Growth Cycle.” J Investig Dermatol Symp Proc 4.323-332.] This gray hair follicle is none other than the gray hair strand that’s at present sprouting from your scalp. Don’t resign your self to gray hair just yet. Although this process may seem like the last word on hair pigmentation, it stands to reason that if oxidative stress can lead to melanocyte death, then the reduction of oxidative stress can allow these specialized cells to re-emerge and kick-start the hair pigmentation process all over again. Part Two:Oxidative Stress: Hydrogen Peroxide & Gray Hair

About the Author: Frederica Hegney is Moderator of the Grey Defense website. Examine our blog site to determine what leads to gray hair and what selected steps you could take on to slow, stop or reverse grey hair. You may also follow her on twitter @GreyHairDefence