Jillian Michaels — The Master Cleanse is BAD for You!!!

It”s the most famous crash diet in history … the Master Cleanse … but according to celebrity super-trainer Jillian Michaels … it”s dangerous for your body.

Michaels was out in Malibu this weekend, when we asked about rumors that Beyonce dropped the baby weight by going on a Master Cleanse … a 10-day program where people are only allowed to consume tea and lemonade mixed with maple syrup and cayenne pepper.

“Don”t do the Master Cleanse,” Michaels told us bluntly … “It”s bad for you.”

Back in 2006, Beyonce told Oprah she shed a TON of poundage by using the program for 14 days … but now, Michaels insinuates Beyonce is more educated about the dangers of the Cleanse … and HIGHLY DOUBTS the singer would ever do it again.

But fear not … Michaels DID offer some healthy weight-loss advice that”s sure to work every time … so watch the clip … and then get off your ass and work out.