I went from a 13 to a 14 when I was 28. Arch doesn’t seem to have flattened. It sucked because I had a nice collection of custom cowboy boots. 14s are also a pain to find in any variety. I prefer a fairly flexible boot with wide toe box and think I could pretty much wear a Crispi Lapponia for everything.
I wore a 9 at high school graduation in a hiking/hunting boot. 8.5 tennis shoe. Wear a 9.5 now 30 years later. I have a very high arch and it’s still pretty high. I also walk on the outside of my foot so I wear down the outside of the sole down by my heal faster than anywhere.
After having kids my wife’s feet grew as well. She can now wear my shoes but it drives her crazy because of how I wear the sole down. She asks me all the time how I can even walk in a straight line. I just tell her with lots of practice and maybe it’s actually her with the crooked feet.
It's a thing, I wasn't aware of it until it happened. I'm a full size + (10.5 to 11.5 / 12) from high school to being 50. I used to have a very high arch and narrow foot but it's flattened and spread out a bit so now they're just low-volume and it's a bit easier to find good fitting boots and shoes. I still use Sheep Feet insoles in my hunting / hiking boots as they're the best I've found.
Funny thread, thought it was just me. I am 6’3”, 200 lbs and 66 years old. My shoes and boot sizes vary a lot, but have gotten bigger. Measure to an 11.5 on a shoe size scale, but wear everything from a 10 (Lacrosse Aerohead Sport 3.5mm) to a 14 in an insulated Lowa Renegade hiker. Generally try on a 12 and adjust accordingly. Moral of the story: Try on before buying.
Age 33, started running 3 years ago and went from size 10 regular to 11 wide. Always had a collapsed arch but my feet have spread out even more. Luckily I bought most of my boots a little bigger with room for socks to start with!
Your tendons and ligaments stretch over time. Fun fact pregnant women release a hormone called relaxin that accentuates this to get them ready for birth but going up in shoe size is a common thing from what I gather.