Kim Kardashian says she sleeps just 5 hours a night — though experts don't recommend it

• Kim Kardashian says she gets up at 5:30am daily for a workout after just five hours of sleep.
• Some other highly successful people, like Martha Stewart and Jack Dorsey, get little shut-eye.

After a lifetime of self-proclaimed people-pleasing, Kim Kardashian has declared her 40s the decade she puts herself first.

"My 40s are about being Team Me," the 41-year-old TV star, model, entrepreneur, aspiring lawyer, and mom of four told Jen Wang for Vogue's February cover story.

"I'm going to eat well. I'm going to work out. I'm going to have more fun, spend more time with my kids and the people who make me happy," she continued. "I'm going to put my phone down. Unfollow if I don't want to see something on Instagram."

But getting more sleep is not in Kardashian's plan. "Living her life means eating plant-based and rising daily for a 5:30 AM workout — typically after only five hours of sleep, Kim's baseline to function," Wang wrote.

While sleep experts say, and research shows, most people need between seven and nine hours of sleep a night for optimal cognitive performance and even beauty, Kardashian's minimalism in that department is shared by many of fellow rich and famous.

Some successful people sleep less to work more

The American Sleep Association says most adults need seven to nine hours of sleep nightly for optimal health. Sleep deprivation, by contrast, is linked to decreased concentration, memory impairment, a lack of cell growth and repair (which in turn negatively affects your appearance), and in some animals even a shorter lifespan.

But some people seem to be outliers, whether they sleep less to work more or simply find they can function well without much shut-eye.

Donald Trump, for one, has boasted of getting just three to four hours of a sleep a night, while Martha Stewart says she gets four, and Jack Dorsey says he gets four to six, Insider previously reported. Like Kardashian, Dorsey's 5:30 am alarm is reportedly set to squeeze in a jog.

Designer Tom Ford, meanwhile, attributes his success to energy over talent, needing just three hours a night.

Other celebrities, though, swear by sleep as the secret to success. Amazon founder Jeff Bezos says he makes getting eight hours of sleep a priority, and author Malcolm Gladwell — an expert on success — snoozes for up to nine, work-life publication Balance the Grind wrote.

Basketball legend LeBron James spends half the day asleep, logging 12 hours between nights and naps, he told CBS Sports. "There's no better recovery than sleep," he said.