Image source: Weight Watchers International

What happened

Shares of Weight Watchers International, Inc. (WW -3.49%) rose nearly 15% as of 11:30 a.m EST today, not because of surprise earnings or a new business partnership that could drive earnings, but because Oprah -- one of Weight Watchers' most famous spokespeople and investors -- revealed in a new commercial that she has lost more than 40 lbs. using the Weight Watchers plan.   

So what

Weight Watchers' updated weight-loss program, which the company says leads to 15% more weight loss in the first two months than the company's earlier program, launched a new commercial featuring Oprah. In the commercial, the billionaire personality and business mogul tells viewers that if they are thinking of trying Weight Watchers, they just need to "take the leap" and start the new program. "I can honestly tell you, I struggle no more," Oprah says in the ad.

Oprah first teamed up with Weight Watchers in late 2015, when she took a 10% stake in the company for $43 million. Oprah has since been a company cheerleader and advisor, and today, she has helped to make the company and herself a little richer. Long term, though, the company may still face some serious challenges.  

Now what

Weight Watchers has had a volatile last few years. The company made an impressive run through March 2012, up to around $80 per share, though the stock plummeted the next three years down to just 5% of that value by June 2015. Oprah has been able to boost the stock a few times in her short tenure there. Shares spiked in 2015, when Oprah announced her new role and position in the company, and again when she announced some weight loss success in January. Even following today's bump, though, the stock is down nearly 50% year to date.

Weight Watchers posted a relatively solid most recent quarter, with revenue and EPS up 2.7% and 38%, respectively, year over year. Still, much of that earnings success was due to a tax issue that allowed the company to pay just 10% tax for the quarter, and Wall Street hasn't been convinced the company will be able to overcome some of its challenges to continue growing earnings going forward.

Congratulations to Oprah on her success, but until Weight Watchers can start to show consistent growth under its new program -- and take care of hurdles such as completing their search for a CEO -- it might be best to push yourself away from the table on this one.