DoubleLine's Gundlach says investors should add commodities in portfolios: CNBC

"I think investors should add commodities to their portfolios," said Gundlach on CNBC, pointing to the "remarkable" inverse relationship between the total return of the S&P 500 and the S&P Goldman Sachs Commodity Index.

"You go into these massive cycles," he said. "The repetition of this is almost eerie. And so if you look at that chart the value in commodities is, historically, exactly where you want it to be a buy."

Gundlach noted that commodities are just as cheap relative to stocks as they were at turning points in previous cycles that began in the 1970s and 1990s. The S&P Goldman Sachs Commodity Index is up 5 percent this year, versus the S&P 500's 19 percent gain.

Fundamentals are also at play in commodities, Gundlach said. He pointed out that global economic activity is increasing, a tax cut could boost growth and the European Central Bank is implementing "absurd" stimulative policies in the euro zone. "I mean, GDP in Europe...Germany is higher than the U.S. for the last year-over-year in nominal terms," he said.

(Reporting By Jennifer Ablan; Editing by Chizu Nomiyama and Cynthia Osterman)