Billionaire Elon Musk prefers caffeine-free Diet Coke over the original—here's why

Elon Musk may have an $180 billion fortune, but one of his favorite drinks costs less than $1 a pop.

In a tweet posted early Monday morning, the 51-year-old Twitter CEO shared a photo of his bedside table which, along with two replica guns, a water bottle and a large number of ring stains, also included four cans of caffeine-free Diet Coke.

Musk wasn't always partial to the caffeine-free version of the drink, which comes in a gold can rather than the classic silver. In fact, the entrepreneur used to drink eight cans a day — on top of his coffee intake — as recently as 2007.

A can of Diet Coke has 46mg of caffeine, meaning Musk was consuming at least 368mg of caffeine each day from his soda intake alone. One can of Red Bull, in comparison, has 80mg of caffeine.

"I got so freaking jacked that I seriously started to feel like I was losing my peripheral vision," he said in an interview with Inc at the time. "Now, the office has caffeine-free Diet Coke."

But that's not to say Musk doesn't still enjoy a traditional Diet Coke every now and then. In June, the Tesla CEO tweeted that he enjoys it at the movies.

Musk isn't the only billionaire with a penchant for the calorie-free Coca-Cola alternative. Former U.S. president Donald Trump famously loves the beverage, and Bill Gates — who, like Musk, once held the title of world's richest person — in 2014 admitted that he starts his day with a can of Diet Coke and drinks "three or four" each day.

"All those cans also add up to something like 35 pounds of aluminum a year," Gates wrote.

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