Congratulations on birthing your first grey hair! You must be so proud, no?
A general rule of thumb is that 50% of 50-year-olds will have about 50% grey hairs – the so-called 50-50-50 rule. While this isn’t strictly true*, it is well known that Caucasians are more likely to turn grey sooner than African Americans and Asians. But before you rush out to stockpile hair dye if you’re feeling at risk, first check with your parents and/or grandparents. The exact timing of your journey to resembling Dumbledore or Gandalf the Grey (whichever you love the most, with/without the beard) is mostly pre-determined by your genetics and you are likely to go grey at a similar time in your life as your parents and grandparents.
Delaying the inevitable is, however, a highly lucrative business. In the USA, approximately 2 billion dollars are spent on women’s hair colouring products each year and $150 million on men’s. As such, there is a plethora of research examining the ‘hows’ and ‘whys’ of greying hair. Much research tries to find out whether or not we can stop or slow it.
Sun exposure, smoking and certain drugs and chemicals can speed the rate at which your hair turns grey due to ‘oxidative damage’. Each can cause a build of hydrogen peroxide within the cells of the hair follicles (the pores from which your hair grows out of), potentially killing off melanocytes. Our body is able to protect itself by removing hydrogen peroxide using an enzyme called catalase. But as we get older the amount of catalase decreases.
It has been claimed that eating foods rich in catalase (such as spinach and avocado and/or taking catalase-based nutritional supplements) may boost catalase activity and reduce hair greying. Present research says that this is highly unlikely because the catalase we eat in food is normally completely destroyed by enzymes in the gut. Catalase-rich greenery is nevertheless good for you (as so by all means use it as an excuse to get stuck into some veg!) but be highly sceptical about supplements as their safety has yet to be confirmed.
Ironically, certain components of permanent hair dyes called ‘resorcinol’ and ‘lawsone’ may actually increase the rate at which you might be going grey as they can slow the rate of melanin production. These substances penetrate the hair follicles and inhibit key processes involved in melanogenesis (they inhibit an enzyme called tyrosinase).
But all is not lost. ‘Enalidomide and tamoxifen are two anti-cancer drugs which have been linked to hair re-pigmentation. That’s right – drugs that could restore our natural colours! Behold, the elixir of eternal (hair) youth – grey hair may be reversible after all! Be advised though, for these aren’t the sort of drugs that anyone wants to take unless they really need to. Researchers hope that they can identify what it is in these drugs that causes the colour restoration and create less toxic drugs that have the same anti-greying effect.
There is still for the silver foxes and President Obamas of the world but the cosmetic industry has a lot of work to do before we can benefit from these drugs’ side effects. So for now, it’s a good idea to avoid too much sun, not smoke, eat a good diet, and enter old age gracefully. Failing that, start putting some money aside for all those hair appointments.
Answer by Amy Timmins
*A 2012, a published study revealed that between 45 and 65 years of age, 74% of people were affected by grey hair with a mean intensity of 27%.