Zoe Kravitz thinks having Botox injections to stop sweating is ''dumb''.

The 'Big Little Lies' actress hit out at the trend for the procedure, insisting it is a ''scary'' concept and urged her fans not to try it because they need to perspire.

Asked what beauty trends shock her, she told America's Vogue magazine: ''Botox for sweat. That is the dumbest, scariest thing I've ever heard. Don't do that--sweating is key.''

Although the 30-year-old actress didn't single out anyone in particular with her comments, Chrissy Teigen recently admitted she'd had the injection to stop herself sweating.

She wrote over a clip of her being injected: ''@drjasondiamond is my favorite human. ''BOTOXED MY ARMPITS.

''TRULY BEST MOVE I HAVE EVER MADE.

''I can wear silk again without soaking woohoo! (sic)''

In the video, the 'Lip Sync Battle' star - who has Luna, three, and Miles, 14 months, with 'All of Me' hitmaker husband John Legend - shared how painless it was and breathed a sigh of relief as she admitted she was scared.

She said: ''That really isn't anything.

''It looked very frightening.''

And the doctor told her: ''That's it.''

Although it was her first time having Botox under arms, Chrissy previously revealed she had her armpit ''sucked out'' to make her ''feel better in dresses''.

She shared: ''I had an armpit sucked out, which was one of the best things.

''It's a big secret, but I don't care.

''It was nine years ago or so.

''And I had two inches to my armpit. Now it's back though, so now I've gotta pay for [liposuction] again.''

However, Chrissy admitted that it was ''the dumbest'' thing she's ever done.

She continued: ''It was so easy. It made me feel better in dresses; I felt more confident. It was the dumbest, stupidest thing I've ever done. The dumbest, but I like it, whatever. I have no regrets, honestly.''