Why do so many American servicemen in WWII look so old?

Dental and orthodontic care (or the lack thereof) can really change the appearance of the mouth. I wonder if young men back then had more crooked teeth, or fewer teeth in their mouths than we would expect today.

And the older ones had disproportianaly lower survival rates for one reason and another.
One lesson of WWI was that kids didn’t do well in the regular army: they tend to fall asleep while on duty. It was a lot harder for a 15yo to enlist in WWII.

One lesson of WWII was that people over 25 didn’t survive as well in combat and POW roles.

Leading to the present situation: in Aus, 18-24yo at enlistment.

Some men were in their 30’s when joined the service . My dad was in WW 1 and had to lie about his age , he was too young . He had no birth record , he was born in Russia around 1892.

I don’t think it’s just WWII or even B&W photos. I noticed a long time ago that people photographed in general in times gone by tend to look older than their present-day counterparts of an equal age.

Fear, stress, lack of sleep, fatigue, bad food, and seeing people around you shot to pieces. There’s no mystery. War isn’t noble or invigorating. It’s exhausting and dirty. Young men lose their youth very quickly.

I would guess that the major factor in making WWII GI’s look older is that the B&W film used then had much less exposure latitude than modern B&W or color film.
This causes strong highlights and deep shadow in the pics. Detail will be lost in the gray areas such as facial features that we use to judge the age of a person.

But looking at footage from the Vietnam War, those guys definitely look younger.

I used to think that people from my father’s (he was in WWII) generation always looked older than those in my generation, and my sister agreed with me. My dad explained that it’s the clothing and hairstyles that give that illusion. All the girls my age (I was a teenager at the time) wore long, straight hair while those of my mom’s generation had shorter, curled hair. My mother still had her hair curled for the week at the salon, and wore the same type of dresses as in her high school pictures. Boys in my dad’s yearbook had short hair while my generation had longer hair. Since the elder generation generally still wore their hair in the same way as they aged, and also wore clothes similar to when they were younger, I had associated my parents’ age with their fashion.

Yeah, it’s funny how kids in photos from a hundred years ago will sometimes look like little old people. Especially the ones working in the mines and mills.

It’s probably a combination of things. even now, if I look back at the yearbook I got in first grade, the 8th-graders back then all seem like they were in their 20s. But if I look at my 8th grade yearbook, we all looked like a bunch of kids.

Well, hell, the dang war’s been over for more than seventy years! How young do ya want 'em to look?

That Lt. Leo Jones in a photo from the OP’s link looks like he’s about 17.

McNamara tours.

It’s something you see in pre World War Ii photos of baseball players. They look old

http://baseballhall.org/sites/default/files/externals/9302f9ba4ff31b599f4c26b9f2439bb0

This photo was apparently taken in 1929 (It can’t be later than 1932). Going left to right Jimmie Foxx is 21, Babe Ruth 34, Lou Gehrig 26 and Al Simmons. I assume they were reasonably decently fed growing up but they spent a lot of time outdoors. I wonder if soap was made differently…not as much skin conditioners as today.

If you want an example of a ballplayer who looks older to us than his biological age, consider Eddie Collins. He looked like an old man while he was still an active player.

With the exception of Ruth, they all look like guys in their mid-20s. They’re a bit pudgier than today’s highly trained athletes are on the whole (the John Kruks of the world notwithstanding).

And… Colby Rasmus has never looked young… maybe not old, but never young.

The only one in that picture who is overweight is Ruth. Foxx was always very muscular and fit. Gehrig and Simmons look lean.

Uniforms in those days were loose-fitting, which tended to even things out. Slim players looked fatter, and fat players looked slimmer.

If you want to see an out-of-shape contemporary ballplayer, check out Bartolo Colon.

My father (AVG/CBI WW II) always claimed it was the life they lived (even before the war), the uncertainty of life back then, and nutrition standards back then. He went into the service younger than he should have but even then he had already worked in the coal mines as a breaker boy and worked the farm and he had earned his weathered-older-looking face. He looked older in uniform at 18 (without his hat) than my brother did at 25 after having done two tours in Nam.

I’ve got all kinds of photos of my dad in WW-II and he looks young. But at the same time he looks like an adult.

Maybe we’re seeing the same thing from different age points. To me, today’s young adults look like they live in their parent’s basement.

Don’t underestimate the effects of smoking. During that time period, nearly everyone smoked to some extent. Regular tobacco use will make you look significantly older.