Glenn Beck reveals serious illness

• The conservative radio and TV host says he's hidden his illness for years


• He went from doctor to doctor before he found the answers he was looking for


• Beck says he's been given a clean bill of health: "My brain is back online in a big way"

(CNN) -- Glenn Beck shared Monday a secret he's kept from almost everyone for years: He's been battling a serious and rare illness.

"It has baffled some of the best doctors in the world. It has frightened me and my family, as we didn't know what was happening," the conservative radio and TV host said on TheBlaze, a network he founded.

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Eventually, he learned what was wrong: he had a variety of ailments, including an autoimmune disorder and adrenal fatigue.

Speaking through tears, the former Fox News host detailed the progression of his illness and the symptoms he suffered.

Beck said he struggled to remember names, faces and conversations. At other times, his hands would shake and he would be forced to curl up into a ball.

"While I was at Fox, the pain would get so bad that my camera crew, our executive producer Tiffany and I, had worked out hand signals so they would know when to take the camera off of me," Beck said.

"We didn't know at the time what was causing me to feel as though, out of nowhere, my hands and feet, or arms and legs would feel like someone had just crushed them, set them on fire or pushed broken glass into them."

Beck said he rarely slept, but was never tired.

After taking a test for people with traumatic brain injury and testing in the bottom 10%, Beck said he was told he would no longer be able to function in about five to 10 years.

He went from doctor to doctor and tried different diets and medications, but nothing really worked. Beck began to search for his replacements.

At the same time, he said, Beck and his wife continued to look for answers and found them at the Carrick Brain Centers, a rehabilitation center in Texas.

"We went and after a few short visits they found that I had several things going on -- from an autoimmune disorder to adrenal fatigue, and they found the connection on everything that was going on," Beck said.

"Me never having to sleep was finally understandable. The last sign of adrenal failure is a hyperextension of your adrenal glands. In other words, I didn't need sleep. I could have been lifting cars during my time at Fox!"

After months of treatment and changing the way he eats, sleeps, works and lives -- along with hormone treatment and intensive physical therapy -- he believes he has reversed the process.

"My brain is back online in a big way," he said. "I have received a clean bill of health."