This article has been updated on October 30, 2014.

Everybody wants to find the fountain of youth. Though literature tells us that is a fool's errand, it hasn't stopped companies from cashing in on a renewed focus on health in developing countries across the globe.

Nu Skin Enterprises (NYSE:NUS) is one such company, offering personal care products under its Nu Skin brand, as well as nutritional supplements under the Pharmanex brand. Shares have plummeted 65% year-to-date. With investors looking to see if the company is a buy at these lower prices, there are three key pieces of information every investor needs to have before buying shares of Nu Skin.

Asia is the Driver of Growth
Though the company is headquartered in Utah, Nu Skin's most important markets are actually all located in Asia. That section of the world accounted for 82% of the company's revenue in 2013. So to really get an idea behind where the growth is, look no further than Mainland China.

To get an idea of what a huge jump in sales China had, consider that in 2011, that region accounted for 19% of all sales. By the end of 2013, it accounted for a whopping 43% of all sales.

Investigations into company practices
As impressive as the growth in China is, it also represents an enormous liability. Shares of the company dropped over 40% in a two-day period in January. The culprit was an article in the Chinese newspaper, People's Daily, calling the company an, "illegal pyramid scheme." The very next day, the government announced that it was beginning an investigation into the company.

At first, it looked like the company might not be affected as much as many had worried. During the first quarter, sales in China were up 63%. That, however, was followed up with more sobering news: sales in China were down 12% and 3% overall during the second quarter, causing many to fear the worst. 

Actually, not too expensive
As you might expect, with worries about Chinese sanctions hanging over the company, shares aren't unreasonably priced. Herbalife (NYSE:HLF) and Avon (NYSE:AVP) represent peers that are worth comparing Nu Skin Enteprises to. Both companies focus on health supplements and beauty products, and both utilize a network of independent resellers to get products directly into consumers' hands.

Take a look at how these three companies stack up in terms of valuation.

 

Nu Skin

Herbalife

Avon

Market Cap

$2.9 B

$4.6 B

$4.8 B

3-Year Rev Growth

24%

15%

(4%)

3-Year EPS Growth

36%

15%

(55%)

P/E

8

9

13

Sources: Yahoo! Finance, SEC filings

Clearly, companies that focus on multi-level marketing are in the cross-hairs. That's the only way to explain such low P/Es for companies that are showing growth rates as impressive as Herbalife and Nu Skin.

Investors need to be extremely cautious moving forward. While investigations into Nu Skin's practices could turn up no foul play in China -- and thus provide a major boost to its sales force in the Middle Kingdom -- that's impossible to predict.

For that reason, I would strongly caution investors to limit their exposure to such a risky play, and make sure they have diversified holdings to offset some of this risk.

Fool contributor Brian Stoffel owns shares of Apple. The Motley Fool recommends Apple. The Motley Fool owns shares of Apple and has the following options: long January 2015 $50 calls on Herbalife Ltd.. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.