Zuckerberg acknowledged that he expects this will mean people spend less time on Facebook, but he hopes the time they do spend "will be more valuable".
The co-founder of the world's largest social-media business saw his fortune fall US$3.3 billion (NZD$4.5b) on Saturday (NZ time) after he posted plans to shift users' news feeds toward content from family and friends at the expense of material from media outlets and businesses.
The idea is to help users to connect with people they care about, not make them feel depressed and isolated.
"We can speculate that the concerns reflected in Zuckerberg's post may very well have been driving these declines", Pivotal's Brian Wieser wrote in a note.
We serve you ads that make us money, which we use to pay reporters and editors to go out and get you more stories.
Shares of Facebook slid more than 5 percent to $177.31 in premarket trading Friday after the change was unveiled.
A large part of brands and media companies' strategies is to post articles and videos from their pages to engage consumers - items that aren't considered "meaningful interactions" between people.
Facebook and other researchers have particularly homed in on passive content.
Zuckerberg predicts users will spend less time on Facebook as a result of these changes. As there will be a reduced number of posts from publishers and business.
But Facebook gave scant details about how it would define what's "meaningful".
But the changes may spell trouble for the ecosystem of companies that have come to rely on Facebook's platform - including news organizations, bloggers and businesses - as a way to reach potential customers and readers. In real life, people don't point at the same news article as their friends and say, "THIS".
The goal of the overhaul, ultimately, is for something less quantifiable that may be hard to achieve: Facebook wants people to feel positive, rather than negative, after visiting.
According to CNBC, Twitter stands to gain from Facebook's decision when it comes to selling advertising, with traffic for media companies dependent on Facebook as a distribution platform, set to diminish.
The move will not affect advertisements - users will continue to see the same ads they have before, "meaningful" or not.
Facebook has always been criticized for creating "filter bubbles", the echo chambers of friends and like-minded people whose views are reinforced by their friends' posts on the platform.
While he acknowledges that Facebook may never be completely free of malign influences, Zuckerberg says that the company now makes "too many errors enforcing our policies and preventing the misuse of our tools".
Stories and clips that draw comments and likes or are shared by users are more likely to be seen, Facebook said in the email obtained by Bloomberg.
A study published in August by NetBase found that Facebook is still the preferred brand of Internet users. "We won't know until we see what happens". The company has been dogged by questions about how its algorithms may have prioritized misleading news and misinformation in News Feeds, influencing the 2016 US presidential election as well as political discourse in many countries. The move may help Facebook stem a drop-off in "organic" posts - the kind that Facebook is now trying to highlight - that's been a problem for the network for years.
Adam Mosseri, Facebook's Head of News Feed, also put out a statement that said the social network would "prioritise posts that spark conversations" and "To do this, we will predict which posts you might want to interact with your friends about, and show these posts higher in feed".
"No matter how well we do on Facebook and how great our videos are, making high-quality videos itself does not bring us any profit", said Cho.
Still, in some ways, this new focus takes Facebook back to its roots as a way to connect students on college campuses.
"This will be one of the more important updates that we have made".