The secret to keeping a pair of jeans forever is to stop washing them, according to the CEO of the company that invented blue jeans 141 years ago.

Chip Bergh, CEO of Levi Strauss & Co., says that not putting a pair of jeans in the washing machine makes their shape and color last longer.

"If you talk to real denim aficionados, they tell you don't wash your blue jeans," Bergh said Tuesday during an interview at Fortune magazine's Brainstorm Green conference.

Not only does the CEO encourage others to do it, he doesn't wash his own jeans.

"These jeans are maybe a year old and these have yet to see a washing machine," Bergh said, referring to the dark blue jeans he was wearing.

"I know it sounds totally disgusting," Bergh continued, adding that he has yet to get a skin disease. "I know it does."

Levi Strauss & Co. began in 1853 when Bavarian-born immigrant Levi Strauss moved to San Francisco and started a dry goods business, according to the company's website. In 1872 he partnered with Jacob Davis, a tailor from Nevada, and invented a "riveted-for-strength" type of work wear made from brown cotton duck material and true blue denim.

The U.S. Patent and Trademark Office issued a patent for the jean, titled "XX," to Strauss and Jacob in 1873. The XX later became known as the 501. Levi's has since become world renown for making long-lasting, durable apparel.

Instead of washing jeans, experts suggest turning them inside out and placing them in the freezer overnight once a month to kill order-causing bacteria, according to ABC News. Another alternative is spraying the jeans with white vinegar or vodka and letting them air dry.

Other leaders in the fashion industry agree with Bergh's advice.

"I never wash my Levi's" fashion designer Tommy Hilfiger once told TMZ, according to ABC News.