Emerging markets can be a physician-investor's gold mine or money pit, and over the past few years, that roller coaster has not stopped investors from throwing billions of dollars into countries like Pakistan and Peru. According to a recent article in Time, the iShares MSCI Merging Markets Index exchange-traded fund, which tracks stocks from countries like Taiwan, South Africa, Turkey, and Poland, is up 89% over the past 2 years—a drastic difference from the S&P 500's 18% gain. And drops that occurred in countries like India (29%) and Egypt (37%) have not seemed to dull investors' interest. Time says that when it comes to emerging markets, as economies of certain countries (eg, China, India, etc) take off, other countries rich in natural resources, like Brazil and Chile, get pulled along when commodity prices peak.

While that assumption can be a lucrative venture, financial planners recommend allocating as much as 5% of your portfolio to emerging markets, but generally no more because of unpredictable risk.