Winfrey's participation in Weight Watchers was valued at $ 160.18 million when markets closed on Tuesday. It quickly fell when the company released its results after the markets closed, falling to $ 112.1 million, erasing $ 48 million in value just minutes after trading.
The initial investment of Winfrey, however, is still in the dark. She bought 6.4 million shares of Weight Watchers at $ 6.79 per share in October 2015, worth $ 43.2 million at the time, according to a document filed by the Securities and Exchange Commission. She has also joined the board of directors of the company.
Last year, Winfrey sold part of its stake in the company. She now holds 5.4 million Weight Watchers shares, according to a document filed by the SEC in January.