BRADENTON, Fla. (AP) -- Vince Palella's brother got him started on supplements.

"His wife is a health food nut," said Palella, a 76-year-old retired contractor who wanted to atone for years of smoking and lunches that were "more drinking than lunch."

He subscribed to a chiropractor's newsletter they recommended. Each issue focused on a topic, such as osteoporosis, and Palella wrote to the guy about his back problems.

"He even wrote back to me and recommended what products I should use and how much of them," Palella said. "I just kept reading his newsletters and he'd recommend certain supplements to take for this problem and certain supplements to take for that problem."

When Palella learned he had cancer, he added the chiropractor's "prostate cancer protocol" to the other combos he was taking. They had names ending in "plex" and he had no idea what they contained. He swallowed more than three dozen pills each day, and was thrilled to learn that his ex-wife, also a chiropractor, could get them for half price instead of the $700 they would have cost him.

"I said, `Boy, I can take more of this now. I can afford more of the good stuff.'"

And so it went until a dietitian at Tampa's Moffitt Cancer Center asked if he were taking any supplements. He had always said 'no' when doctors asked about medication use.

"I didn't think they were medications. They're not prescription, they're not drugs. This is all natural substances, made from natural products," he explained.

But he told the dietitian the truth. She was alarmed, and at his next visit, "She had a file ready for me," Palella said. She said that some of his herbal pills could interfere with hormone treatments for his cancer, and showed him a recent medical study raising concern about that.

"It scared the hell out of me. I thought, 'I'm not helping things here,'" Palella said.

He cleaned out his medicine cabinet.

"I thought I was really doing a great thing and strengthening my immune system," he said. "I feel so stupid."

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