"Don't part your hair in the middle, your part will get wider and wider"

Or so I’ve been told/threatened by the person who trims my hair and by one of my girlfriends and a former girlfriend a few years ago.

Urban legend? Verified truth? What’s the straight dope?

How exactly would that work if it were true?

• the act of parting your hair and then combing the left side to the left and the right side to the right somehow puts stress on the hairs right at the location where the part is? (How? Why?) If you part your hair 66% / 33% instead of right down the middle, wouldn’t you then be stressing your hairs THERE, at THAT part?

• the weight of one’s hair somehow makes hairs disappear from the middle of one’s head when the ones in the middle are the farthest from the distant ends on either side of the head? Again, why would that not cause the same issue if hairs were parted in a different spot? It would be different individual hairs but some hairs somewhere would be the ones that are the farthest from where they are combed to, yes?

• the top of one’s head is a place hairs are prone to depart and if you part your hair there it is somehow worse because, umm, hell I dunno, maybe if other hairs were being draped across that area it would reassure the top-of-head hairs and they’d stay planted?

I can only offer my personal experience with this. For 30 years I have been parting my hair in the middle. (I feel it’s fair that way.) Also, tying it in a ponytail for a goodly number of years. My hairline is slowly drawing back from my forehead, but nothing suspicious is happening at the part.

Mine is parted in the middle too, a result of the Leif Garret style popular in the 70s.

Since male pattern baldness begins on the top of the head I suspect that’s what may be going on with the suggestion that the part gets wider and wider. People who part on the side can get away with a comb-over look for a while.

Anyway, no baldness in my genes so, no issues for me.

I’ve been parting my hair down the middle for almost 50 years. No sign of widening part so far.

And Leif Garret’s part seems to have widened enough to reach his ears on both sides.

I think it’s just as you say, male pattern baldness.

Either that, or Louis C. K.'s really let himself go.

I have no idea nor thoughts to contribute on why this might be so, but I can make a (relatively lame) speculation on why some people might think this is so.

Parting the hair partially exposes a narrow line of scalp to the sunlight. Perhaps this might be more so with a part on top than a part more to one side. Maybe there is some thinking that exposing that narrow strip of scalp to sunlight will cause hair loss right along that line.

It’s always seemed to me that a part looks wider in the middle of the head than it does on the side of the head. Since hair is angled at about 30° (it doesn’t grow straight out at a right angle to the scalp), it also seems to me that if it’s parted on the side, it’s tensioned because it’s forcibly pulled against the angle of growth, so it curls a little and closes the gap. If you part it in the middle, it lays flatter because it’s going with the grain and the part appears wider.

I think these people are trying to tell you that the “butt-cut” just doesn’t flatter you.

I’ve been parting my hair all my life, too. The one thing that does happen is, your hair naturally begins to fall at the part so when you try to style it differently, it feels weird and is harder to do.

But then again, my hair is very curly so maybe it’s a facet of the texture. Maybe silky soft hair doesn’t do this…mine isn’t.