Melinda French Gates believes it's "so dumb" to try and maximize productivity by getting only a few hours of sleep.

The billionaire philanthropist, who recently announced that she's sponsoring a $12.5 billion grant toward women's rights, told Vanity Fair last week that she aims to get seven to eight hours of sleep each night. And she shared a negative view of the executives she's encountered who boast about sleeping only a few hours each night.

"Some of us didn't want to be around them! Let's be honest!" French Gates said, referencing CEOs and tech entrepreneurs who promote, in her eyes, a form of performative sleep deprivation.

Notable business leaders who've discussed their scant sleep habits include former PepsiCo CEO Indra Nooyi, who said in 2018 that she typically worked until midnight and woke up at 4 a.m. Former U.S. president Donald Trump and ex-Yahoo CEO Marissa Meyer have also talked about only needing to sleep four hours, or less, at night.

Elon Musk, currently the world's richest person, was once among them — bragging about pulling all-nighters and sleeping under his desk as his electric vehicle company Tesla tried to meet its production goals. He's since changed his tune, and now aims for at least six hours of sleep per night, he told CNBC last year.

"I've tried [to sleep] less ... Even though I'm awake more hours, I get less done," Musk said. "And the brain pain level is bad if I get less than six hours [of sleep]."

Amazon founder Jeff Bezos and Microsoft co-founder Bill Gates — French Gates' ex-husband — have shared similar stories. Bezos now makes getting eight hours of sleep "a priority," he told Thrive Global in 2016: "For me, that's the needed amount to feel energized and excited."

In his youth, Gates was influenced by other entrepreneurs bragging about not needing enough sleep, leading him to believe that "sleep is laziness and unnecessary," he said on his "Unconfuse Me with Bill Gates" podcast last year. Now, he aims for a minimum of seven hours of sleep each night, he said.

The real connection between sleep and productivity

Medical experts agree with French Gates and her ex-husband: Adults ages 18 to 60 need at least seven hours of sleep per night, according to the Centers for Disease Control and Prevention. Sleep deprivation can lead to health issues including heart disease, kidney disease, high blood pressure, diabetes, stroke, obesity and depression, says the National Institutes of Health.

For some people, that's a frustrating fact — and a convenient one to ignore, in the name of maximizing every moment of time to get ahead in their careers. Roughly one-third of employed U.S. adults sleep less than six hours per night, a 2020 CDC study found.

Work is the most common activity that prevents people from getting enough sleep, says research from the American Academy of Sleep Medicine. In some industries — think finance, health care, tech — the long hours can lead to a cultural glorification of sleep deprivation, especially among younger employees.

Yet the difference between a sleep-deprived brain and a healthy one is stark, research shows. Getting enough sleep is essential to achieve peak physical and mental health, according to the CDC, which adds that sleep deprivation can even mimic the effects of being drunk.

"I can tell you with authority that when I'm exhausted, when I'm running on empty, I'm the worst version of myself," media mogul Arianna Huffington, who once wrote a book on the subject, told CNBC Make It in 2018. "I'm more reactive. I'm less empathetic. I'm less creative. And all of us can testify to that."

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