Lenny Kravitz's daughter's weight loss secret: Clay?!

Most celebrities lose weight for movie roles by eating chicken breast or hiring a personal trainer. 

We've never heard of anyone drinking clay. 

But that's what US actress Zoe Kravitz did to lose 20 pounds, or about 9 kg, for her role as an anorexic and bulimic character in the upcoming movie The Road Within. 

"I did a cleanse," she told Us Weekly. "I tried to do it the healthiest way as possible, even though it's not healthy to do.

"I ended up drinking clay because it cleans out your body and fills you up."

"Awful"

Us Weekly noted that other stars like Shailene Woodley - who starred in Divergent with Kravitz - drink clay-based drinks made with bentonite clay, which is composed of aged volcanic ash.

The website Wellness Mama states that bentonite clay is able to draw in toxins like a sponge, and can be used "externally or internally". 

If ingesting clay sounds disturbing, well, Kravitz assures you the experience was not fun. 

She called it "awful" and said she would "never encourage anyone" to do the same thing. 

Sources: New York Daily News, Us Weekly, Wellness Mama