04/27/2012 05:13 pm ET Updated Apr 27, 2012

Peter Bergen's 'Manhunt' Reveals Details Of Osama Bin Laden's Last Days

Not only was family life a source of solace for Osama bin Laden, the former al Qaeda leader strongly believed polygamy was a religious obligation. These are two of the revelations in Peter Bergen's upcoming book, Manhunt: The Ten-Year Search for Bin Laden -- from 9/11 to Abbottabad, according to the Washington Examiner.

Bergen, who is considered a top authority on bin Laden, writes that bin Laden had to go out of his way to keep up with his wives. In an excerpt published by the Examiner, the book reveals that the former Al Qaeda leader reportedly dyed his hair and "used Avena syrup -- a natural Viagra made from wild oats –- which was found in large supply in the compound."

Avena syrup is a botanical product that is used as a natural sweetener or to increase sexual desire. After the discovery of Avena in bin Laden's compound last year, NBC News medical editor Nancy Snyderman explained that while there is a lot of folklore around the potential of the plant as a natural Viagra, not much research has been done into the subject. "Of course, it could have provided Osama with a psychosomatic boost," she noted.

Manhunt is scheduled to go on sale May 1 to coincide with the one-year anniversary of the death of the former al Qaeda leader. The book details the years-long search for bin Laden and his capture in the Pakistani city of Abbottabad.

Peter Bergen is a security analyst for CNN and has authored several books. Bergen interviewed bin Laden together with CNN colleague Peter Arnett in 1997. The Crown Publishing Group claims Bergen was one of only two journalists who received access to "a treasure trove" of materials seized in bin Laden's compound and was "the only outsider" to have toured the compound.

On Friday, bin Laden's family left Pakistan for Saudi Arabia, after the al Qaeda leader's widows served 45-days sentences for entering Pakistan illegally.