While Cory Monteith’s weight plummeted, his demons were quietly resurfacing.

The Glee star, who admitted himself to rehab for substance abuse last week, has been showing off a much leaner body as of late— a now-obvious hint at trouble.
 
When 6-foot-3 Cory dropped from about 235 to 215 pounds last fall, he credited the loss to a healthier lifestyle, including yoga classes and “fewer Snicker bars.” But NYC-based addiction expert Dr. Jean Cirillo, who doesn’t treat Cory, says substance abuse can result in dramatic weight loss like Cory’s. “If an abuser is drunk or drugged, their mind isn’t clear and they can forget to eat,” she says.
 
 
The 30-year-old actor has struggled with substance abuse in the past, beginning when he was just a preteen. “I used anything and everything,” Cory admitted in 2011. After a family intervention failed to work at age 19, Cory was threatened with jail time after stealing money from a relative to support his habit. 
 
When Cory finally got clean, Lea Michele came along.
 
Cory found love with his Glee co-star, 26, who’s behind his latest effort to seek help. “She was the one who suggested he try rehab to get a handle on things,” Cory’s pal says. 
 
And Lea has been continuously tweeting words of well wishes and thanks to her fans for standing by her man. “Still so overwhelmed by all the love and well wishes we have received from you all,” she tweeted April 2. “My heart is so full.”
 
For more on Cory's struggles and his road to rehab, pick up the latest issue of In Touch, on newsstands now.

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