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Related topics: mutual funds, 401k, investments, retirement, savings

Even with professional management, mutual funds can be risky. A 401k portfolio can be sent reeling if a faulty investing strategy is employed, a portfolio is too tightly concentrated or the wrong funds are picked.

And recovery from a misstep is more difficult than many investors imagine. If your fund declines by 30%, for instance, you'll need a gain of 42.9% just to become whole. If you fund sinks by 40%, a gain of 66.7% is required to catch up; lose 60% and you'll need a recovery of 150%.

This is why mitigating losses is just as important as picking winners.

Here are five mutual funds to avoid:

Vanguard Long-Term Treasury Admiral

Bond funds seem fairly safe, especially when they are chock-full of government securities. What could go wrong?

Well, the bond market has been in a bull phase for more than three decades. In other words, it seems reasonable that there may be a reversal. Moreover, interest rates have been at historic lows but are starting to get volatile.

To top it off, if inflation seeps back into the U.S. economy, prices on government bonds will suffer. The impact will be hardest on longer-term securities and related mutual funds.

Investors need to be wary of funds like Vanguard Long-Term Treasury Admiral (VUSUX). True, the fund has a competitive expense ratio of 0.12% and a good management team. But this will mean little if there is a sustained increase in interest rates.

Keep in mind that the fund has an average maturity of about 13 years. This means that a 1% increase in rates will reduce the portfolio by a whopping 13%.

High interest rates wreaked havoc on bond funds throughout much of the 1970s. Protect yourself and dump Vanguard Long-Term Treasury Admiral before you get burned.

Fidelity Freedom Income

Retirement planning is complex and requires periodic changes in an investor's asset allocation. To help things out, some mutual fund managers have launched so-called "retirement" funds that handle the details for you.

But be wary. These funds can often be costly and too cautious. The result could be that you fail to reach your retirement goals.