Being a billionaire sounds kind of miserable. This week, Twitter CEO Jack Dorsey revealed several of his intense wellness habits to CNBC, and most of them sound like things normal people would explicitly avoid if they had gobs and gobs of money to throw around. For instance, among the ice baths, hot sauna barrel sessions and jog-walking to work, it seems Dorsey, 42, is also into the trendy eating practice of intermittent fasting. What is intermittent fasting? Intermittent fasting, or IF, is exactly what it sounds like: You eat during a small window of time during every day, and the rest of the time you “fast,” or don’t eat. For example, some people choose an eight hour window in which to eat, and then hang back the other 16 hours of the day. The routine supposedly gives you a lot of time and energy for doing other stuff like running a massive tech company and journaling (another one of Dorsey’s trendy wellness habits). Dorsey says he only eats one meal per weekday, and tries to fast on the weekends. (Which, by the way, is really extreme when it comes to intermittent fasting.) “During the day, I feel so much more focused. … You have this very focused point of mind in terms of this drive,” Dorsey told CNBC about intermittent fasting habit. “Certainly, the time back from breakfast and lunch allowed me to focus more on what my day is.” Dorsey is far from the first high-profile name to sing IF’s praises. Stars like Hugh Jackman and Justin Theroux have praised intermittent fasting for helping them get into shape for movie roles. Is it just some baseless trend? No, purposefully denying yourself food when you could just employ a whole phalanx of personal chefs isn’t just some rich person game. Intermittent fasting, if done responsibly, has some serious scientific backing. A 2016 study from the University of Southern California revealed that strategic calorie restriction may actually help you live longer. “Diet can have a remarkable effect on you,” Valter Longo, professor of gerontology at USC Davis, told CNN in 2016. “It can reprogram your body and put it on a path to live longer.” Other studies have backed up IF’s long-ranging health claims. In 2018, three men with Type 2 diabetes reportedly reversed their need for insulin by adhering to an intermittent fasting schedule. Other research suggests IF can reduce the risk of obesity, and in turn all of the health risks obesity presents. However, like any diet plan, IF isn’t for everyone and it isn’t a silver bullet for weight loss. And unfortunately, it won’t make you really rich. Experts recommend talking to your doctor to get some advice before hopping on the IF bandwagon.