Ian Halperin, the author who correctly predicted last year that Michael Jackson had six months left to live, offers ET his take on the late icon's final days.

"The last days and weeks of Michael's life he was extremely frail, confused, rarely slept, rarely ate, and seemed to be more pensive than ever," claims Halperin, the author of a new book about the reportedly troubled twilight of Jackson's life.

Halperin, who says he interviewed more than 2,000 people for his book, says his sources told him the late King of Pop was anorexic, bulimic and, toward the end, "barely ate a crumb." Contributing to Jackson's fragile state, Halperin says, was the alleged influence of prescription drugs.

"Michael was in extreme pain, especially the last few months and weeks of his life. With his tour [looming], the only way he'd be able to get up was with the use of drugs to help him, to numb the pain," the author says. "[Michael] was the first to admit he was in no condition to do a two-hour show. And they were going to camouflage it with old video clips, new video clips, dancers on stage…"

Jackson's respiratory health was so poor, Halperin says, that at one point a lung transplant was considered. "That's what I was told: that it was recommended that he have a lung transplant, but his condition might not hold up."

Halperin's book, Unmasked: The Final Years of Michael Jackson, arrives July 14.