Many investors who invest in alternative mutual or exchange-trade funds lose out by trying to time their investments.
"It's so easy to cash out after a year of bad performance," Glassman said. "They buy in after it does well and they cash out after it's done poorly."
If you invest in one of these strategies, you need to have the resolve to stick with it. Otherwise, you risk leaving returns on the table.
You may also be able to invest in alternative investments directly through your retirement funds. But that should come with a big warning sign, according to Ed Slott, founder of Ed Slott & Co.
"As soon as the markets get shaky, people look for the grass to be greener somewhere," Slott said. "And they always get themselves in trouble, almost all the time."
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Tax rules dictate that you can invest in anything in your IRA except for collectibles, life insurance or S corporations.
But if the investments you make through your IRA are not liquid, you could have a difficult time taking your required minimum distributions once you turn 70½.
You could also run the risk of running afoul of prohibited transaction rules that come with severe tax penalties — losing as much as your entire IRA.
That goes if you invest in real estate through your IRA and then use the property for your own purposes, otherwise known as self-dealing.