For years investors have avoided the scary stuff. But some financial advisers recommend devoting a small chunk of a portfolio to funds that specialize in these riskier areas.

Junk Bonds

High-yield bonds are issued by companies whose finances are too weak to earn an investment-grade credit rating. But default rates have been falling this year, and yields look attractive. The Artio Global High Income fund aims for the middle of the junk universe, trying to limit risk. It s up an average of more than 8 percent annually during the past three years, beating more than 90 percent of rival funds.

Emerging-Market Stocks

Countries like India and Brazil have relatively young populations with rising income. That makes them hot places to invest and emerging-market stock funds have been raking in the cash. But fund expenses can be on the high side, with many charging more than 1.5 percent in annual fees. The Vanguard Emerging Markets ETF tracks the broad market and charges just 0.27 percent.

Commercial Real Estate

The economy might be slowing down, but that can give real estate investment trusts a chance to scoop up properties at bargain prices. Among mutual funds, the Neuberger Berman Real Estate fund holds a variety of REITs and property-development firms, and the Vanguard REIT Index offers a low-cost way to track the sector, with annual expenses of 0.26 percent.

Stock Options

Options are often used by sophisticated investors to hedge their risks, and some funds try to do the same. The Gateway fund writes put and call options against the S&P 500 index and holds a basket of stocks similar to it. The strategy enables the fund to hedge against losses in a falling market and make some money if stocks rise.