from www.foxnews.com – “Saved by the Bell” star Dustin Diamond is spilling the beans on what went on behind the scenes of the mega-successful teen show.

Diamond, 32, has written a tell-all book entitled “Behind the Bell” that shares all the insider secrets of the sitcom, which ran from 1989 to 1993. According to Diamond, the six teen stars were involved in sex, drugs, womanizing, hard partying and even steroids.

Diamond told FOX News that Mark Paul Gosselar, who played Zack Morris, took steroids before starring in “The College Years” spinoff.

“He admitted it to me,” Diamond said. “Plus, you can’t lie to your eyes, if you watch the college years, you can see about 25 pounds of growth in about 2 months of filming.”

SLIDESHOW: Entire ‘Saved By the Bell’ Cast Then & Now.

Gosselar has denied the claims.

Diamond also claims that Mario Lopez, who played teen-hunk A.C. Slater was a “serial womanizer” to put it “nicely.”

According to “Behind the Bell,” producers went to great lengths to portray Gosselar, Lopez, Diamond, Lark Voorhees, Tiffani Thiessan and Elizabeth Berkely as squeaky clean, despite the debauchery that took place on and off set.

“When the finished product came out,” the image of the young stars was wholesome, despite an indicated tendency to let their success go to their heads, Diamond claims.