Oprah Winfrey attends the 'Belief' New York premiere at TheTimesCenter on October 14, 2015 in New York City. (Photo by Jamie McCarthy/Getty Images)

Weight Watchers has been riding high after Oprah Winfrey took a public role in the company, but now they are looking for new management.

Chief Executive James Chambers will be stepping down later this month, and the company is looking for a new chief executive, with Oprah involved in the search.

“This was not a planned transition,” said Morningstar analyst R.J. Hottovy. “It was something that came about in the last several weeks, and it’s possible that Oprah played a role.”

On Tuesday, shares of Weight Watchers declined 6.6 percent, and they are down 65 percent from the initial high reached when Oprah announced that she was buying up shares in the diet company.

“Oprah’s involvement on the board is through 2018, and the board probably wants to give the new guy enough time to benefit from the ‘Oprah effect,’ ” said Jason Schloetzer, a Georgetown McDonough School of Business professor.

Last year, Winfrey purchased a 10-percent stake in the weight loss company, which was an investment of roughly $43 million.