Investors nervous about the prospect of a so-called double-dip recession have flocked into defensive exchange traded funds and bonds.

However, there are additional steps that ETF investors can take to shore up their portfolios, says Russ Koesterich, iShares Global Chief Investment Strategist.

First, within equities, investors can guard against volatility by overweighting defensive sector ETFs such as healthcare, telecom, utilities and consumer staples. [Defensive Sector ETFs, Dividend Payers Limit Volatility]

Also, within the fixed-income slice of the portfolio, Koesterich recommends tilting to investment grade companies rather than high-yield due to lower default rates in an economic pullback. The largest ETF in this category is iShares iBoxx $ Investment Grade Corporate Bond Fund (NYSEArca: LQD).

“Investors holding this fund are generally looking for a relatively safe and consistent income stream,” Morningstar analyst Timothy Strauts writes in a profile of the ETF.

Of course, the bond fund could be hit by rising interest rates and increasing corporate credit spreads.

Finally, investors worried about a recession would want to reduce their exposure to commodities, Koesterich says.

“Commodities tend to be particularly sensitive to economic activity so investors who expect a double dip may want to consider lowering their commodity allocation,” the strategist wrote at the iShares blog. “The commodities to curb back on: Those most tied to economic activity, such as industrial metals, agricultural commodities and energy.” [Copper, Oil ETFs Fall on Growth Concerns]

The opinions and forecasts expressed herein are solely those of John Spence, and may not actually come to pass. Information on this site should not be used or construed as an offer to sell, a solicitation of an offer to buy, or a recommendation for any product.