Let the prisoner's starve... that's torture. Force the prisoner's to eat... well... that's torture too:

Five U.N. human rights experts urged the United States to shut down Guantanamo Bay after concluding the forced-feeding of prisoners and some interrogation techniques amounted to acts of torture, according to a draft report obtained on Monday.
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The survey is the result of an 18-month investigation ordered by the U.N. Commission on Human Rights and was based on interviews by the investigators with former prisoners, their lawyers and families, but not on-site visits.
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The U.N. team rejected an invitation to tour the U.S. naval base at Guantanamo, where more than 500 people have been held since the September 11, 2001, because they would not have been allowed to interview prisoners.

And no on-site visits? They studied the matter for a year and a half, and not once did they step on the base? So what if you couldn't interview them? At least you could walk around and see how they're being treated.

What's really at issue here is not how anyone is being treated. If that's all that they cared about, they would have gone on-site and seen for themselves. All those are just made up excuses. They just don't want anyone to be held, no matter what they did. Well... that's just not gonna happen.