Wall Street was all aflutter Monday about “the Oprah effect.”

She bought 10% of Weight Watchers and the company’s stock soared. Big news.

But anyone who follows pop culture has watched Oprah’s turn-to-gold touch for decades — on books and magazines, movies and television, fashion and lifestyle products, on politics and political causes, and on making stars out of nobodies she has embraced.

Ever heard of psychologist Dr. Phil and health-expert Dr. Oz before Oprah reached out and touched them? Alternative-medicine advocate Deepak Chopra and financial adviser Suze Orman? Lifestyle designer Nate Berkus?

They’re all celebrities now, after years of appearances on Oprah’s daytime talk show led to their own TV shows.

Oprah’s Favorite Things, products she has featured on her show or in her successful magazine, O, very shortly become America’s favorite things after she spotlights them.

Not to mention: Would Barack Obama be where he is now had Oprah not helped elect him president?

Along with Obama, Oprah is among the most influential African-Americans in the nation’s history; certainly, she’s the richest, having made billions over the years.

Now her Midas touch on Main Street has now moved to Wall Street, says Howard Bragman, chairman and founder of 15 Minutes Public Relations, who’s known Oprah since her Chicago local-TV days 30 years ago.

“As much power as Oprah has, she has used her power for good — she hasn’t invested to just watch her stock go up.” says Bragman. “And the reason she is so powerful is her authenticity. She gets involved in things she believes in…She does well by doing good.

“And as long as she remains true to herself and her life and to how things affect her emotionally and physically, she will continue to have this effect.”

The Oprah effect (there was even a TV documentary about the phenomenon in 2009) is most dramatically obvious in publishing and book sales, after she created her Oprah’s Book Club in 1996.

Example: Toni Morrison — whom Oprah loves and whose books were chosen four times (the most individual picks for one author) for the club — got a bigger sales boost from Oprah than from winning the Nobel Prize for Literature.

She and her club, which was created for her long-running daytime talk show, The Oprah Winfrey Show, had a huge impact, not just on the publishing industry and book sales but on the idea of reading for pleasure itself.

Twenty of her picks made it to No. 1 on USA TODAY's Best-Selling Books list. (The Oprah pick with the most consecutive weeks at No. 1 was Ekhart Tolle's A New Earth at 11 weeks.)

Jefferson Graham looks at how Weight Watchers is competing with calorie counting apps like MyFitnessPal and LoseIt to attract digital audiences, on #TalkingTech. By Jefferson Graham