A set of rotting, loose teeth isn't the ugliest health condition prisoners bring with them when they go into lock up.

They bring stuff that can kill them, like hepatitis C and HIV-AIDS.

Eight of 10 prisoners at the North Dakota State Penitentiary used meth.

They get "meth mouth," severe decay and tooth loss.

But they also get jaundice and cirrhosis of the liver from dirty needles and arrhythmia and heart attacks from weakened hearts.

Dr. John Hagan, penitentiary physician, said he was initially amazed at the prevalence of meth use among prisoners.

Their dedication to getting the drug is weirdly impressive.

"They get up every day to find enough money to buy meth," Hagan said. "There's no weekends off; these folks work every day."

A lot of inmates are 30, but their bodies are 60.

As part of a public health initiative, prisoners are screened for hepatitis C, a potential killer. They learn how to keep clean and prevent its contagion.

It's spread from dirty needles and bodily fluids, just like HIV-AIDS.

Meth users, who don't go to prison, unfortunately don't get screened.

"They're probably sick and infecting each other," Hagan said. "This is bad stuff, and I didn't appreciate how bad until I got here."

In the past three years, 16 prisoners with hepatitis C have been treated with Interferon, a cancer drug. It costs $24,000 a year and only a few meet all of the required protocol.

Untreated, hepatitis C can result in liver cancer.

Others are treated for sexually transmitted diseases and then the staff faces the daunting prospect of contacting all the prisoner's sexual partners.

In a meth world of sex for drugs, the men don't always remember even the first names of their one-night-stands.

Meth prisoners often have bad hearts and high blood pressure.

They also have brain damage and in some cases are extremely paranoid and exhibit schizophrenia.

Hagan said he has developed a new level of fear of meth.

"If this were my kid, I would do whatever it takes, no matter how severe, to keep them from entering this lifestyle," he said.