Harbaugh said Wednesday morning he spoke with Lewis. The coach said Lewis "knows there is nothing to it. He understands it's something he's never been involved in."
On Tuesday, Sports Illustrated reported that Lewis sought help from a company that makes the unorthodox product to speed his recovery from a torn right triceps. Lewis missed 10 games with the injury.
"He laughed about it," Harbaugh said, referring to Lewis. "He told me there's nothing to it. He's told us in the past and now that he has never taken any of it."
Baltimore plays the San Francisco 49ers in the Super Bowl on Sunday in the final game of Lewis' career.