Amid what's being called a youth mental health crisis, is social media facing its own 'tobacco moment'?

After two decades of radically changing the way we interact with others, social media may be facing a turning point, as experts study whether excessive use may have a detrimental impact on youth mental health.

For some children, relentless exposure to social media may be one contributing factor for what many experts, including the Surgeon General in a new advisory, say is a public health crisis.

"Our children have become unknowing participants in a decades-long experiment," Surgeon General Vivek Murthy told ABC News in a statement. "And while there is more we have to learn about the full impact of social media use on their health and well-being, we know enough now to take action and protect our kids."

However, many experts are saying that research into social media's impact on mental health is incomplete and nuanced, pointing to some benefits that can be had from social media as well as what they say are significant gaps in evidence for mental health impacts from it -- gaps that some experts say need to be filled with more openness from social media companies.

When asked about the impact of social media platforms on mental health, a representative for Meta, the parent company of Facebook and Instagram, referred to mental health as a "complex issue" and pointed towards other contributing factors such as limited access to health care, the COVID pandemic, and academic pressure.

The Meta spokesperson added, "We want to work with schools and academic experts to better understand these issues, and how social media can provide teens with support when they need it, in a way that acknowledges the full picture."

Representatives for YouTube told ABC News that they have implemented a variety of safeguards for young users, including adding "digital wellbeing features," removing content that "endangers the emotional wellbeing of minors or promotes suicide and self-harm," and "exploring ways to further collaborate with researchers."

A TikTok spokesperson told ABC News that its companies have added user aids to improve youth mental health, such as bedtime reminders and age restrictions. The company also said that it built an application programming interface that includes public data on content and accounts on the platform, which is available to U.S. researchers.

With a concerning yet incomplete picture of the problem, some worry that policymakers are left with a momentous policymaking gamble: take swift action to attempt to mitigate the risk or wait for more evidence while potential harms may accrue. And for veterans of past public health crises – like the decades-long fight to regulate the tobacco industry — they say social media presents some familiar public relations and regulatory challenges.

Landmark advisory

In late May, Murthy issued what may become a landmark advisory on social media.

According to the advisory, "the current body of evidence indicates that while social media may have benefits for some children and adolescents, there are ample indicators that social media can also have a profound risk of harm to the mental health and well-being of children and adolescents."

The advisory added to other warnings Murthy has offered about youth mental health, which he has described as the "defining health issue of our time," and referenced research suggesting that adolescents who spend more than three hours on social media per day have double the risk of negative mental health outcomes such as depression.

Between 2011 through 2021, the suicide rate among young people aged 10 to 24 increased by 60%, according to Centers for Disease Control and Prevention's National Center for Health Statistics.

In addition to the spike in the suicide rate among young people, a February survey from the Centers for Disease Control and Prevention found that nearly three in five teen girls in 2021 reported feeling persistently sad or hopeless, a 36% jump since 2011.

"I issued my advisory on social media and youth mental health because the most common question parents ask me is if social media is safe for their kids. While some kids experience benefits from social media, there is not enough evidence to conclude that social media is sufficiently safe," Murthy told ABC News. "Instead, there is more evidence that many kids are harmed by their use of social media."

With 95% of teens between the ages of 13 and 17 using social media, Murthy's advisory quickly drew comparisons by some observers to a 1964 Surgeon General Report that highlighted the dangers of another common activity: smoking.

At the time, more than 40 percent of adults smoked regularly, according to CDC data. Others see comparisons to the tobacco industry responses to public health concerns.

"I see very much the same tactics of an industry that is diverting attention from its own actions," said Matthew Myers, who founded the Campaign for Tobacco-Free Kids, pointing to how some social media companies have challenged regulation and disavowed responsibility.

However, experts say any comparison between the two public health crises only goes so far.

Ten years prior to the 1964 Surgeon General Report, scientists published growing research outlining the link between smoking and lung cancer. Scientists studying the link between social media and mental health have less evidence to hang their analysis on, not only because the science is still developing but also because the causal relationship is complicated.

"Eighteen years of research, and there just is not any huge directional effect that everybody that knows the research can agree on," said Stanford professor Jeff Hancock, who has done research on how social media impacts mental health.

The start of that research initially viewed social media more optimistically, seen by many as valuable tools to connect communities and notably even promote social and political change.

"I think it was really great at speaking truth to power," said Chris Said, a data scientist who worked for Facebook and Twitter in the 2010s. "But there was at the time a nagging concern in my head, and I'm sure in the heads of a lot of other people that maybe it's not great for everyone."

In addition to the concerns about increased mental health risks for adolescents who spend more than three hours daily on social media, the advisory noted that social media can expose young people to harmful content and risks displacing the time children spend socializing in person during one of the most formative times for brain development.

However, the advisory also notes that social media offers positives for young people. According to Pew Research, fifty-nine percent of adolescents reported that social media helps them feel more accepted -- a finding shared by many young people who spoke with ABC News.

"I was super weird [growing up], and if I only had the context of my school and the world that was close to me physically, I would have really disliked myself and been confused as to why I was so weird, but I was able to find a community online that really built me up," Eric Smith, 27, said about the role of social media in his childhood.

Others, like Jarrod Bates, 34, described early social media platforms as critical to understanding his own sexual orientation while growing up in what he describes as an isolated community.

Social media can also have an inconsistent impact on users unlike tobacco which negatively impacts the health of most of its users, according to Megan Moreno, the co-medical director for the American Academy of Pediatrics Center of Excellence on Social Media and Youth Mental Health.

"Social media isn't like that. It may be that they had a negative interaction one day, and they're feeling really bad about it. And the next day, they have a really positive experience, and it lifts them back out of it," Moreno said.

Adding to the challenge is a lack of available data to study social media's impact on mental health, according to Murthy, who recommended requiring social media companies to share data about the impact of their platforms on youth mental health. Until recently, most social media companies refrained from sharing user data with researchers, leaving scientists with a limited toolbox to understand the impact of social media, according to Hancock.

"We cannot live in a world where Google, Facebook, TikTok and Twitter know everything about us, but we know next to nothing about them," said Nate Persily, a professor at Stanford Law School who has supported legislation to improve data sharing in the United States.

Since the Surgeon General's advisory, researchers from the University of Oxford published new findings using access to internal data from nearly a million active Facebook users across 72 countries, including adolescents users.

"We found no evidence suggesting that the global penetration of social media is associated with widespread psychological harm," the research published on Aug. 8 found.

A Meta spokesperson hailed the Oxford research as a critical step to "understand the full picture" of youth mental health.

While sharing data is critical to understanding social media's impact, the overall lack of baseline data provides less information to inform regulation, according to Zeve Sanderson, the executive director of New York University's Center for Social Media and Politics. If regulation is eventually passed, there are few data points to understand the policy's efficacy.

"I think this leaves legislators largely flying blind, aiming to on the whole make a positive impact on our online environment but without this sort of toolkit that they would have with [a policy issue] like the economy," Sanderson said.

How will this generation be impacted?

The lack of certainty comes as an overwhelming number of young people continue to use social media, and an entire generation has grown up using the platforms.

"We've been surrounded by it. That's how we communicate. That's how we [reach out to] each other. That's how we see current events," said Tony Olivas, a 22-year-old who said he first joined a social media platform when he was 10.

Of the 95 percent of teens who reported using social media, 35 percent said they used at least one social media platform "nearly constantly," according to the Pew Research Center.

The magnitude of the issue leaves scientists and policymakers with a high-stakes public health gamble waiting on stronger evidence to support social media regulation.

According to Murthy, policymakers know "enough" to take action, drawing a comparison to the spike in automotive fatalities in the 1960s that led to safety standards.

"We must establish and enforce safety standards for social media just as we did decades ago for motor vehicles at a time when motor vehicle fatalities were unacceptably high," Murthy told ABC News.

As science develops, the public relations fight about social media's impact has already begun.

Erika Sward, the national assistant vice president for advocacy at the American Lung Association, described the public relations dispute between regulation advocates and social media companies as a "David versus Goliath" situation. She warned that the tobacco industry refined a public relations playbook that is easily replicable across multiple industries.

Myers added that he has observed some familiar tactics utilized by social media companies, including disavowing responsibility, placing blame on parents, and challenging the government's ability to regulate.

At least two non-profit groups have begun raising awareness about the potential impact of social media.

The former owner of Major League Baseball's Los Angeles Dodgers, Frank McCourt, recently launched a multi-million-dollar campaign called Project Liberty Action Network that has spent over a million dollars a week this summer on ads highlighting the potential harms of social media, according to records reviewed by ABC News.

Jim Steyer, CEO of Common Sense Media, which advocates for holding social media companies accountable for their impact on youth mental health, told ABC News that although leaders in the federal government have yet to adequately address the problem, he expressed optimism that a growing movement centered on young people will compel policymakers to action.

"There's no question that … we've reached a tipping point moment, where the public really understands the depth and breadth of the problem related to youth mental health and social media," Steyer said.

If you are experiencing suicidal, substance use or other mental health crises, please call or text the 988 Suicide & Crisis Lifeline. You will reach a trained crisis counselor for free, 24 hours a day, seven days a week. You can also go to 988lifeline.org.