Barstool Sports founder and President Dave Portnoy is echoing his past investment advice that "stocks only go up" and "only losers take profits." However, he pointed out one important condition during an appearance on "Varney & Co." on Wednesday.

"I've always said the caveat, if you have time pressure, that's a different story," Portnoy said. 

"But if you're in my shoes, a young strapping man, and I can wait, time is always on your side in the stock market, Stuart, and the stock market has proven it," he continued.

The Barstool Sports founder noted that "stocks always go up in the long term."

"There's no point where you could have bought stocks, and if you held, they wouldn't be higher," he said. 

While the world went into lockdown in 2020, Portnoy became the poster child of the day-trading craze, livestreaming his daily trading sessions on X, giving followers a glimpse into both his successes and failures as he slung positions worth hundreds of thousands of dollars.

"I'm trading my own money and lots of it," Portnoy highlighted. "I'm having fun. As long as we're still kind of with nothing else to do, I'll keep day trading," he said at the time.

Portnoy's fortune exploded in 2016 when he sold his majority stake in his media company to the Chernin Group, which reportedly valued Barstool between $10 million to $15 million, according to Forbes.

FOX Business' Jonathan Garber and Daniella Genovese contributed to this report.