Going Grey: Why does your hair change colour as you age?

Do you also worry about your grey hair and wonder why is it happening? While previously experts have attributed it to stress, poor diet and even genetics, US scientists have found another answer to why hair turns grey as we grow older.A new study says it is likely because stem cells – which give hair its natural pigment – get stuck as hair ages. The study, published in the journal Nature, was led by researchers from New York University's (NYU) Grossman School of Medicine.What did the study find? Why is this study important? Let’s find out.Why does hair turn grey?Growing and losing hair is a common occurrence. New hair comes from hair follicles found in the skin. This is also where melanocyte stem cells (McSCs), which are responsible for producing protein pigments that provide hair its colour, reside, as per BBC.Some stem cells have the ability to develop into many different cell types. They can also move between growth compartments in hair follicles, as per The Guardian.

When these cells stop moving, it causes greyness in hair.

Researchers studied this process in mice by focusing on McSCs, which are also present in humans.During normal hair growth, McSCs regularly oscillate between compartments of the developing hair follicle.[caption id="attachment_12483652" align="alignnone" width="640"] When the stuck stem cells stop moving, it causes greyness in hair. Pixabay (Representational Image)[/caption]As hair ages, sheds and then grows back over time, more number of melanocyte stem cells “get stuck in the stem cell compartment called the hair follicle bulge, where they remain”, reported The Guardian.Once these cells stop their movement and become fixed in this stem cell compartment, they fail to regenerate or mature into melanocytes completely. As no pigment is being made, hair turns grey or silver.The NYU Langone Health team used special scans and lab techniques to examine the ageing process in cells, reported BBC.Researchers found that these stuck McSCs fail to regenerate as they lose exposure to signals that would allow them to become mature cells and produce pigments responsible for colour.“It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for greying and loss of hair colour,” the study’s senior investigator Mayumi Ito, was quoted as saying by The National.ALSO READ: Stress isn't the only thing giving you white hairWhy is the study significant?Scientists believe that if these findings are also true for humans, then they could pave a potential path to reverse or prevent grey hair.The study’s lead investigator, Qi Sun, a postdoctoral fellow at NYU Langone Health, said: “The newfound mechanisms raise the possibility that the same fixed-positioning of melanocyte stem cells may exist in humans.[caption id="attachment_12483662" align="alignnone" width="640"] Scientists believe that if these findings are also true for humans, then they could pave a potential path to reverse or prevent grey hair. Pixabay (Representational Image)[/caption]“If so, it presents a potential pathway for reversing or preventing the greying of human hair by helping jammed cells to move again between developing hair follicle compartments,” The Guardian quoted the researcher as saying.These scientists now plan to explore ways to restore the movement of McSCs or physically transfer them back to their germ compartment where they can produce pigment.ALSO READ: Will humans be able to grow young again after study makes reverse ageing possible in mice?According to the British Association of Dermatologists (BAD), this study can also help in understanding the treatment of some kinds of cancers better.Dr Leila Asfour from BAD told the United Kingdom's broadcaster BBC: "The obvious implication of this research, when it comes to the general public, is that it means being one step closer to finding a way to reverse our grey hairs."But this study's results help the medical field understand better other conditions where these stem cells may have a role - for example, understand the underlying nature of the deadliest skin cancer we treat called melanoma."The research can also help with alopecia areata, a medical condition where the immune system attacks hair follicles, triggering hair loss. Those suffering from the condition sometimes get white hair when it regrows, Dr Asfour added.Speaking to BBC, Dr Yusur Al-Nuaimi from the British Hair and Nail Society said this study could open up more treatment options in the future."The recent study in mice adds to our understanding of the hair follicle and how the pigment-producing cells function. We are already discovering more about the potential of stem cell therapies for conditions including hair loss and studies such as this one, with new findings about the colour-producing cells, may lead to an array of future treatment options for our patients,"Dr Al-Nuaimi stated.With inputs from agenciesRead all the Latest News, Trending News, Cricket News, Bollywood News,India News and Entertainment News here. Follow us on Facebook, Twitter and Instagram.