10 Mindblowing Things That Happen As You Age

...but we don't know what will either.

Sure, we know how greying happens: Pigment in hair is produced in cycles using something called melanocytes. Simply put, hair can't grow and produce pigment at the same time, so it will alternate between the two phases. Unfortunately, hair has a limited number of pigmentation cycles in it, and once the melanocytes become exhausted, uncoloured hair will grow with its characteristic white or grey colour.

The only thing is, we're not 100% sure as to why this happens in the first place and exactly why the pigment-making melanocytes should even run out int he first place.

There are certain medical conditions that affect the greying of the hair and the age at which a person goes grey is strongly linked to their genetics. Stress, however, almost certainly won't make you go grey.

The common myth that stress turns your hair white is a little bit of coincidence and a little bit of confirmation bias. For example, world leaders such as Barack Obama and Tony Blair were noticeably much older and greyer at the end of their terms in office than at the beginning and many people put this down to stress. However, it probably has a lot more to do with the fact that their "most stressful years" have coincided with their last pigmentation cycle.

Most people will go through their most stressful years just as they begin to grey, perhaps when they're at the pinnacle of their career or their kids have just turned into horrible teenagers - either way, a lot of people tend to come to false conclusions to explain their greying locks (it couldn't just be that they're getting old could it?)