Oprah makes $70M in one day from Weight Watchers deal

Weight Watchers (WTW) may help dieters lose weight — but the stock is fattening Oprah Winfrey's fortune by $70 million in just a day.

Just the word that Winfrey took a 10% stake in the company — buying 6.4 million shares and being awarded options to buy 3.5 million more — caused the stock to more than double to $13.92 a share.

Winfrey was a massive winner from the one-day spike to the tune of $70 million. However, it's just a drop in the bucket for Winfrey, who is worth an estimated $3.1 billion, according to Forbes.

Oprah buys 10% of Weight Watchers, stock soars

The massive jump is a tangible sign of the weight Winfrey still carries with investors and consumers. The sum's so large that it would pay Winfrey's Weight Watchers monthly membership fee of about $43 for 1.6 million months or buy her about 28 million Weight Watchers meals.

While Winfrey is a huge winner from the announcement, she's not the biggest. Half of the company's stock, or 29.4 million shares, is owned by private investment firm Artal. That translates into a $209.9 million gain for the day.

Shares of Weight Watchers had been decimated for years as the company's business model faded amid competition and other diet options. Investors appear to be betting that a marketing boost from Winfrey will reinvigorate the brand.

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BIGGEST OWNERS OF WEIGHT WATCHERS

Investor, shares owned (in millions)

Artal: 29.4

Oprah Winfrey: 6.4 *

Fidelity: 6.1

Vanguard: 1.8

Capital Research and Management: 1.7

Source: S&P Capital IQ, USA TODAY

* Excludes options