Editor's note: This story was first published in May 2013.
(CNN) -- Jim Heston, an American guesthouse operator in Cambodia, has lived a life in denim and has the photos to prove it. There were the dungarees he wore as a little boy, the dark bell-bottoms he had on for a hike up Japan's Mount Fuji, and the Levis straight-leg 501 jeans he's stayed with for the past 36 years.
At 54, Heston doesn't get embarrassed anymore, "but if I had to share any of these blue jean moments a few years back, I would have been a little more reluctant," he says. In particular, there was the snapshot of him on a Hawaii beach in a Daishiki and jeans his mother extended with red fabric because he was growing faster than his pants were wearing out.
May 20, 1873, is considered the birthday of blue jeans. Readers shared their favorite and most cringe-inducing moments in denim (hello, acid wash) to mark the occasion.
"They're the most unique piece of clothing everyone owns because they keep changing as you wear them," said Angelika Corrente, who runs Denimhead, global trend forecaster WGSN's denim division.
A few facts about denim:
1. Jacob Davis, a tailor in Reno, Nevada, came up with the idea of riveted pants in response to a customer whose pockets kept ripping. He feared someone might steal his idea and recruited Levi Strauss, owner of dry goods wholesaler Levi Strauss & Co., as a business partner. They obtained a patent on May 20, 1873.
2. Denim jeans -- or trousers, waist overalls or dungarees -- started out as work-wear for hard labor in mines, factories and fields. By the 1980s, as high fashion brands began to introduce the concept of designer jeans, the shape and fit began to slim down.
3. Consumers in the United States buy approximately 450 million pairs of jeans every year.
4. On average, U.S. consumers have seven pairs of jeans in their wardrobe, according to Cotton Incorporated.
5. Environmental awareness has pushed denim laundries to improve techniques for bleaching and coating jeans to give them different looks, Corrente said. Where lots of water, aggressive washing and sandpaper was once the norm for creating that worn vintage look, lasers and and ozone gas cameras are now being used to minimize water waste and chemical runoff.
6. This year's trends are marked by a hybrid appreciation for fads of other eras. You're as likely to see someone rocking the heavy raw denim popular among '60s bikers and rebellious youth, an '80s-inspired high-waisted, flower print, or the acid-washed, ripped-up grunge look of the '90s.
CNN's Emanuella Grinberg contributed to this report.