Elon Musk, the uber-successful tech mastermind behind Tesla and SpaceX, has to get his power from somewhere, and though he’s a genius businessman and inventor, he used to get that power from the same source as all of us regular people: caffeine. According to a report from Business Insider, Musk used to drink eight cans of Diet Coke everyday, along with several cups of coffee, back when he was working 100 hours per week.
“I got so freaking jacked that I seriously started to feel like I was losing my peripheral vision,” Musk once said of the addiction.
He hasn’t totally kicked the habit, though he’s trying to cut out caffeine: He claims his office is now stocked with caffeine-free soda.
Researchers recently found that it’s safe to drink up to 400 milligrams of caffeine everyday. There are 46 milligrams of caffeine in one 12-ounce can of Diet Coke, meaning that he was consuming a minimum of 368 milligrams of caffeine a day, not including all the coffee he drank after getting his soda fix. Bear in mind that there's an estimated 155 milligrams of caffeine in just one 8-ounce cup of Starbucks Pike Place Roast coffee. Yikes, "jacked" indeed.
Though Diet Coke doesn’t contain any sugar, it does contain aspartame, an artificial sweetener that is 200 times sweeter than sugar. Aspartame may cause cancer, although studies have thus far have been inconclusive.
Coffee, on the other hand, may actually be healthy: Some scientists think that it can reduce your risk of developing diabetes and heart disease, and like red wine, coffee has powerful antioxidant properties.
Musk is certainly one of the smartest guys on the planet right now, but given these facts, his choice to keep drinking soda may not be his best idea. Might we suggest actually giving up soda and going back to coffee? After all, something has to give him the fuel he needs to finally invent flying cars.
This story originally appeared on Foodandwine.com.