Rodney Zimmers was 21 years old and 135 pounds when he got off heroin and cocaine for good. Three years later, he was still drug free but had ballooned to 250. He blames his weight gain on the high-calorie, high-sugar food served in rehabilitation.

It's easy to look at the stunning model and actress Amber Valletta and assume that her life has been charmed.  But just this summer, Valletta admitted that during her rise to fame in the 1990s, she was a drug and alcohol addict.

"It's as slow and as painful and as horrifying as any other disease you could possibly succumb to," Gabel said. "People need to start thinking about it as a long-term terminal illness. Just like you would think about cancer. We're never going to be done with it. You're never in remission. And it's terminal if it’s not treated. People need to understand that and hold on tight. Just keep fighting."

For years, people with alcohol and drug problems have been referred to as alcoholics and addicts.

Society’s view was they were to blame for their lot in life because they lacked discipline or willpower. But over time, research determined addiction is much more complicated and, in fact, that addiction is a primary chronic disease of the brain influenced by genetics and environment.

Amy Winehouse sang about it in a Top 10 hit. Celebrities have embraced it as almost a rite of passage. And one former First Lady made it a key part of her legacy. We’re talking rehab, as in the process of undergoing extensive — and sometimes costly — treatment for substance abuse, often in an inpatient setting.