What causes people to get grey hair and thin hair when people get older?
I see all these ads on TV talking about grey hair and thin hair and some people that go bald when they get older and this got be wondering what causes this?
And also all the billions of dollars these companies spend money on and there is no cure or treatment.
The FDA allows these companies to sale creams and gels that do not work and medication people take that do not work.
The grey hair is simply due to pigmentation cells in hair follicles dying as people age. Your hairs are constantly falling out and being replaced with new-grown ones, and as the pigment cells die, the new hairs sprouting from that follicle have less melanin to color them. So they look grey, and eventually white, rather than black or blond or red or whatever your original color was.
As time goes on more and more of your hair follicles lose their hair-coloring ability because of their pigment cells dying, so the colored hairs you lose are replaced by more and more grey or white ones.
Hair thinning and baldness is more complicated and I’ll let somebody else answer that one.
The gene for male pattern baldness is on the X chromosome, which is why it’s far more common in men; it also appears to have varying degrees of penetrance. It’s related to testosterone levels, and women who for whatever reason lose their estrogen supply or take testosterone can also experience it if they aren’t genetically inclined.
Rogaine (minoxidil) is a topical agent that has varying efficacy in hair regrowth, and Propecia (finasteride) is a testosterone blocker, used in higher doses to treat BPH, and also has varying efficacy in addition to unpleasant side effects, impotence being one of them.
Since I’ve gone through menopause and also started taking an estrogen blocker for breast cancer, my own body hair has changed dramatically; my pubic hair has become thinner and sparser, whereas the hair on my legs and chin have thickened slightly.
This part is not true.
Here’s what is true:
Congress prohibits the FDA from regulating these almost-medicines. Thereby allowing the snake oil salesmen to sell lots of useless creams and supplements and vitamins and all the rest.
Why did Congress do that? Graft & lobbying. The kingpin is
who’s a thoroughly reprehensible human as that wiki will detail.
What causes people to get grey hair and thin hair when people get older?
Their children.
That’s what I came in to say. I gather that Rogaine (minoxidil) has varying levels of effectiveness for different people, but I have the good fortune to be among the 20% or so of users who get pretty dramatic results.
There have been lots of ads for ball caps that appear to be lined with laser emitters - supposedly, these thicken hair growth.
Seems like snake oil to me - expensive snake oil. Even if they were proven to work, I’m not sure I’d spend hundreds or thousands to get one. But obviously some people do.
I’m 67 and have yet to see my first gray hair. However, I see fewer and fewer of the remaining hairs - I definitely inherited the hair gene from my dad’s side of the family. I remember all of his sisters wearing wigs in their later years. When my dad died at 72, he was just starting to show some gray, but his hair was definitely thinner.
My mom, on the other hand, at 87 have thick, wavy, very gray hair - my sister got that gene. And so it goes…
At 62 I’ve got skin, not hair, above my eyes for several inches. With lots of hair in the middle above my nose. So much more full-head-of-hair than bald or even balding.
It’s even all the same color it was when I was 30: uniformly gray. Win some, lose some. 
Within this vale
Of toil
And sin
Your head grows bald
But not your chin --use
Burma- Shave
I"m 62 and just seeing my first gray hairs. Which is a relief, because the rest of me looks 62, and I really, really don’t want people thinking I dye my hair.
As to thinning, a bit. It doesn’t seem to be pattern baldness – no receding hairline – but definitely thinner than it was when I was 20, or 30, or even 40.
So it seems to me that gray hair is inevitable, thinning isn’t. Thinning or balding seems to be mostly a male thing, while graying is universal.
I’m not losing hair, gravity is just causing it to migrate 
And the gray is definitely there, at 53. But I have many, many more important things to worry about in life, both balding & graying are way down on the list. For many folks they’re apparently more important.
I’m a guy. I’m 58 and about half of my blonde hair is grey/silverish and that’s mostly on the sides. A little thinning, but not bad. I still have a full head of hair. My dad had a super-high forehead, though mine isn’t that bad nor noticeable.
I have some gray hair, but no children.
Yea Melanin is the natural pigment that occurs in your hair, skin, and eyes. The more you have the darker your hair, skin, or eyes might be.
But I’m not sure what that has to do with grey hair.
If you had kids you’d have more.
Or things like diet or stress could also cause grey hair and thin hair?
It’s some sort of combination of androgens (not just testosterone), age and genetic predisposition. Teenagers don’t lose their hair, despite being chock-full of all that stuff- something changes as we age and our hair falls out. ISTR that something similar is why anabolic steroid users will also lose hair as a result of their use.
Because the melanocytes (the cells which produce melanin, or pigment) in human hair follicles are prone to dying off as we age.
Maybe. My mother had 2 children and zero grey until early 80s. By the time she died at 98, her hair still had much of its original colour although it was getting kind of a grey “tinge” to it.
A high-school classmate lost her hair for unknown reasons, and had to wear a wig.
I, at 75, still have dark brown hair (and yes, I’ve been accused of dying it). No kids.