As 2013 begins, now's a good time to look at the future prospects for the stocks you own. If you don't know where a company's headed in the next year and beyond, then it's impossible to make an informed decision about whether you should add the stock to your portfolio -- or sell it if you already own it.

Today, I'll look at Herbalife (HLF 1.41%). The seller of nutritional supplements and weight-management products had put up lackluster numbers through mid-December, but in the past three weeks, the bottom has fallen out of the stock. Below, you'll learn more about Herbalife's prospects for 2013.

Stats on Herbalife

Average Stock Target Price

$75.43

Full-Year 2012 EPS Estimate

$4.03

Full-Year 2013 EPS Estimate

$4.56

Full-Year 2012 Sales Growth Estimate

17.4%

Full-Year 2013 Sales Growth Estimate

11%

Forward P/E

7.1

Source: Yahoo! Finance.

Will Herbalife heal itself in 2013?
Analysts have huge hopes for Herbalife, with a target price that's fully 130% above where the shares currently trade. With solid earnings and revenue growth projected for 2013, the stock's forward P/E of just 7 seems ridiculously cheap.

But in the past few weeks, the fight over Herbalife's legitimacy has gotten red-hot. Short-seller Bill Ackman of Pershing Square Capital Management gave a presentation explaining the rationale of his massive short position, alleging that the company is a pyramid scheme and has zero value for shareholders. Herbalife has promised to answer Ackman's accusations in a presentation scheduled for next Monday, but the market wasn't willing to wait and sent the stock plunging more than 35% in just three days.

Fundamentally, the stock seems poised to capitalize on a popular trend. With obesity drugs from Arena Pharmaceuticals (ARNA) and VIVUS (VVUS) getting a lot of attention but not yet creating sales, those looking for weight-loss alternatives have had to go either with nutritional solutions like Herbalife or custom-food programs Weight Watchers (WW 7.54%) or NutriSystem (NTRI). Without inquiries from Ackman and David Einhorn casting those figures into doubt, Herbalife would look like a huge value.

Looking forward, a lot will depend on how the company comes off on its analyst day next Monday. Without a strong performance, more selling pressure could send shares even lower.

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