Bill Gates used to think of meditation as "a woo-woo thing tied somehow to reincarnation," he writes on his blog, Gates Notes, and he "didn't buy into it."

Today, he and his wife Melinda practice consistently.

"I'm certainly not an expert, but I now meditate two or three times a week, for about 10 minutes each time," says the self-made billionaire and Microsoft co-founder.

"I now see that meditation is simply exercise for the mind, similar to the way we exercise our muscles when we play sports," he continues. "For me, it has nothing to do with faith or mysticism. It's about taking a few minutes out of my day, learning how to pay attention to the thoughts in my head, and gaining a little bit of distance from them."

He says it helps him focus, and science backs him up: Meditation can not only improve focus, but it can keep your brain young, help reduce stress and boost memory.

Gates isn't the only successful business leader who practices meditation: Salesforce CEO Marc Benioff, Thrive Global CEO Arianna Huffington and billionaire entrepreneur Oprah Winfrey, among others, meditate regularly.

Huffington tells Lifehacker that, besides sleep, mediation is the most effective tool for productivity and performance, and Benioff tells the New York Times that it has helped him listen more closely before making decisions.

If you want to get into the habit, too, Gates suggests reading "The Headspace Guide to Meditation and Mindfulness" by former Buddhist monk Andy Puddicombe. After years of not buying into meditation, Puddicombe was "the person who turned me from skeptic to believer," says Gates.

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