This how Harry Styles gets his sexy washboard abs!

Los Angeles - Harry Styles is on a "bullet coffee diet."

The One Direction hunk, 21, who already has a tiny 26-inch waist and washboard abs, has revealed he's on a new weight loss regime to suppress hunger pangs.

Sipping on the bizarre concoction, he explained to the Times newspaper's Style magazine: "It's black coffee with a spoonful of butter in it and spoonful of coconut oil, mixed up together. I've been on it for two days. You don't get hungry."

And, although his demanding career with the boy band often means he doesn't have a single second to himself, the handsome star has admitted he takes his health very seriously and regularly meditates to release his stress.

He explained: "I wear 26inch waist women's jeans. Boom ... I do yoga, a bit of meditation, Pilates. I'm reading a book about Buddhism."

But it's not just his mental health he likes to keep in tip-top condition as he also likes to lash out at a punch bag and get his heart rate up with a run every day.

His bandmate Niall Horan, 22, added: "Harry is superfit. He does 12 five-minute rounds of boxing every day and goes for runs."

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