There's a little-known reason.

By Perri Ormont Blumberg
Woman with Blue Jeans from Back
Credit: Westend61/Getty Images

Roses are red / Denim is blue / Have you ever stopped and pondered why this is true?

But really, though. Have you ever wondered why jeans are made in the signature color of blue? Well, now's your chance to find out. Believe it or not, jeans date back to the 19th or 18th century (conflicting reports exist on the true birth of the denim jeans as we know them) and there's even an entire website dedicated to their storied origin at

The blue hue actually has to do with the traditional dyes used when jeans were first made. "People have been wearing blue jeans for centuries. Originally, the blue color came from a natural indigo dye. The dye was chosen for the way it interacted with cotton," explain Nathaniel Lee and Jessica Orwig on Business Insider. Interestingly, there's also a reason denim gets its trademark faded appearance after a few washes. "When heated, most dyes penetrate the cotton fibers but indigo dye attaches to the fiber's surface, instead. The result? During each wash, some of the fibers and dye molecules escape, giving jeans that signature faded look over time," continue Lee and Orwig.

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