DoubleLine CEO Jeffrey Gundlach said Tuesday that historical and economic indicators point to a likely buying opportunity for commodities such as oil and gold.

"If you ever thought about buying commodities, ... maybe you should buy them now," Gundlach said in a webcast organized by his firm.

He pointed out that by comparing total returns of the S&P Goldman Sachs Commodity Index with the S&P 500 over the last several decades, there are clearly defined points at which commodities outperformed stocks, leading to a sharp increase in stocks, and vice versa. For example, stocks far outpaced commodities during the dotcom bubble of the late 1990s into 2000. But commodities went on to rally hard until they peaked during the global financial crisis of 2008.

"We're right at that level where in the past you would have wanted commodities instead of stocks," Gundlach said, noting that commodity prices stopped falling in 2016 and the global economy is "definitely hanging in there." He said he does not see a recession likely for at least the next six months.

The S&P GSCI is up nearly 56 percent from its low in January 2016 after plunging more than 30 percent in 2015. The index is up just over 6 percent this year, while the S&P 500 has rallied more than 17 percent.

Gundlach also expects the U.S. dollar index's next major move will be lower as the Federal Reserve is unable to tighten monetary policy as much as they plan. A weaker dollar also helps commodity prices and emerging market assets, which Gundlach said he still likes.

In a response to a question about whether having 10 percent of a portfolio in gold is "too much," Gundlach said he would rather put 10 to 15 percent of his investments in commodities broadly rather than gold alone.

The investor also said the falling yield curve between the 2-year and 10-year Treasury yield is "getting to the point where it's worth watching." That fact that "people are starting to explain away the yield curve" indicates to him the U.S. economy is closer to the middle of the tightening cycle than the beginning.

"It's pretty relentlessly flattening," Gundlach said. "If the [yield curve] goes to zero then we get a flashing yellow light for [a] recession."

DoubleLine's $54 billion Total Return Bond Fund is up 3.6 percent year to date, according to Morningstar.

This summer, Gundlach put a big bet on the return of volatility to the market, predicting the would tumble. He bought a bunch of put options on the index, a bet that it would fall and a move he described as a bullish bet on volatility. In August, Gundlach predicted the VIX would double to 20.

Just the opposite has happened for most of this year. The S&P has climbed while volatility as tracked by the CBOE's Volatility Index, or VIX, is down 20 percent. Only recently has Gundlach's bet been in a position to benefit. The VIX is up 21 percent this month and 16 percent so far this quarter.

Gundlach said on Tuesday's webcast that since the VIX jumped from below 10 to above 17 a few days after his August forecast, "I'm going to call it good enough."