The researchers analyzed results from survey data taken between May 2020 and May 2021 from individuals aged 18 years and above. The survey sample included quotas for sex, age, and race and ethnicity from each of the 50 states in the U.S. to ensure it was representative of the country’s population.

Survey questions included the nine-item Patient Health Questionnaire (PHQ-9) to assess for depressive symptoms. Questions examined whether participants had “little interest or pleasure in doing things” and whether they were “feeling down, depressed, or hopeless” on a four-point scale.

The researchers also queried participants on:

• their use of social media, such as Facebook, Instagram, and TikTok
• whether they consumed any sources of COVID-19-related news in the last 24 hours
• the number of social supports they have available to discuss problems
• the number of face-to-face meetings they had with nonhousehold members in the previous 24 hours

For the data analysis, the team included participants who had filled out the surveys at least twice and had an initial PHQ-9 score of less than 5, indicating less than mild depression.

Overall, 5,395 people completed two surveys. Their average age was 55.8 years old, while 65.7% were female, 4.7% Hispanic, 10.6% Black, and 76.3% white.

From their analyses, the researchers noted that Snapchat, Facebook, and TikTok use in the first survey had associations with a significantly greater risk of an increase in self-reported depressive symptoms.

They also noted that COVID-19-related news participants consumed in the last 24 hours alongside the number of social supports and daily face-to-face interactions only impacted results linked to Snapchat.

While TikTok and Snapchat use had correlations with depressive symptoms among those aged 35 years and older, but not those younger than 35, Facebook use had associations with depressive symptoms among those under 35, but not those older than 35.

The researchers say that due to the observational nature of their study, they cannot ascertain why social media use may have links to depression. However, they identify possible mechanisms.

“One possible explanation for our results is that people who are at risk for depression, even if they’re not currently depressed, are more likely to use social media,” Roy H. Perlis, M.D., M.Sc., lead author of the study, told Medical News Today.

“Another is that social media actually contributes to that increased risk. With our study design, we can’t distinguish between the two. What we can exclude is the possibility that depressed people are more likely to report social media use, which was a limitation of some previous studies,” he added.

When asked to explain what might be behind this association, Sara Makin, M.S.Ed. NCC., LPC., and founder and CEO of Makin Wellness, who was not involved in the study, highlighted that when isolated, people may turn to social media as a way to feel more connected. However, this may have an inverse effect and therefore result in depressive symptoms.

She also noted the effect of social comparison: “Social media often only shows people ‘living their best lives’ or the positive things that are happening like purchasing a new house, getting a new job, graduating from college, etc. Most people compare their failures to others’ successes, which can make us have negative thoughts about ourselves.”

While it seems as though rates of depression increased during the COVID-19 pandemic, some question whether social media use had a casual role at all.

“Big limitations make it difficult, if not impossible, to conclude anything worthwhile from the findings, “ Craig J. R. Sewall, a postdoctoral fellow at the University of Pittsburgh, who was not involved in the study, told MNT.

“The item they used to measure use of [social media] platforms is a simple ‘yes/no’ response to this question: ‘do you ever use any of the following social media sites or apps?’ So a person [who] used Instagram, for example, 5 years ago and a person [who] used Instagram 5 hours ago would both answer ‘yes.’”

“That’s a big problem and renders this finding practically meaningless: In adjusted regression models, Snapchat, Facebook, and TikTok use at first survey were significantly associated with greater risk of increase in self-reported depressive symptoms,” he continued.

“Because the question about [social media] use was phrased the way it was, even if they found an association between [social media] use and depression, they would have no way to ascertain whether that [social media] use was recent or a long time ago, whether they frequently visited the [social media] platform or whether it was a ‘one-and-done’ situation [or both]. As a result, it’s a big stretch to conclude that participants’ increase in depression between May 2020 and May 2021 had anything to do with whether they used certain [social media] platforms,” he explained.

“I believe the ‘link’ found in this study is dubious but, generally, if there is a link [between social media] and depression, there could be a number of explanations. In the time of COVID-19, I believe the most plausible explanation is that many people experienced increases in depression due to the myriad negative impacts of the pandemic.”

– Dr. Sewall

“At the same time, people had to rely more on digital technology like [social media] to connect with friends, colleagues, and loved ones. So people who became more depressed due to the pandemic may have relied on [social media] more as a coping mechanism,” he concluded.

“Explaining the links between social media use and depression requires a lot of careful thought and precise methodology, “ said Dr. Fisher. “In my personal opinion, this should be done in a way that moves away from cross-sectional, self-report measures like are employed in this study and toward measures that consider the individual (sometimes called idiographic methods), and those which measure social media use in a more objective fashion (like using device logs or a data donation framework).”

“I just don’t know that we have enough evidence from this paper to decisively conclude that there is a link between social media use and depression, much less that the causal directionality here is that social media use [leads to] depression. It’s also possible that those who were more depressed during the pandemic happened to use social media more (e.g., to connect with friends). The methods used here don’t let us conclude either way,” he added.

The researchers conclude that we need to understand the relationship between social media use and mental health better.

“Even if social media use is only telling us about underlying risk, rather than causing it, can we understand why?” said Dr. Perlis. “Might we be able to intervene to prevent depression and anxiety? We hope that our work will inform both mental health researchers and policymakers in thinking about how to study and potentially act on this relationship. What we can’t​ continue to do is simply ignore this association or try to wave it away as a statistical artifact.”

The researchers note that their study has several limitations. Firstly, they say they could not properly control for all factors that may have influenced their results. They stress that their research does not prove causation and that social media use may “simply be a marker of underlying vulnerability to depression.”

When asked how these findings should influence public health, Ms. Makin said: “For one, limits for the amount of social media that one consumes should be set. This can be easily done by going into your settings on your [smartphone], so once you have reached your limit for the day, you can no longer access the app.”

“Likewise, research may need to be done to determine what is an appropriate amount of time to spend on social media where it makes us feel good but does not cause us to become fixated on the lives of others and cause feelings of depression. It may also be helpful to suggest changes about the way that we interact and react on social media with others. Teenagers and adolescents who have social media accounts may need to be monitored more closely to make sure they are not victims or perpetrators of cyberbullying,” she added.

However, Dr. Sewall believes these findings should not influence public health recommendations, given the “flimsy” evidence:

“If the hope is to help people improve their well-being during these very difficult times, I believe it would be a waste of time and resources to focus on people’s [social media] use. [It would be] much better to focus on some of the myriad other issues that have been impacted by the pandemic — like financial security.”

Dr. Fisher agreed that these findings should not directly influence public health recommendations, “at least not in an extreme way.”

Dr. Fisher added: “I do hope that findings like these generate some momentum toward pressuring social media companies to share their data with independent researchers, because this is likely the only way for us to come up with evidence that is actually conclusive with regard to the links between social media use and depression.”

“I am all for increased accountability for social media platforms, but the fact is that social media use is very idiosyncratic, and for some people, it’s positive, and for others, it’s negative, just like many other behaviors.”

“We are likely to actually set our understanding back if we are too quick to pathologize everyday behaviors. I would be disappointed if healthcare practitioners and other public health officials use the findings from this study as justification for any kind of causal link between social media use and depression, especially in a general sense.”

– Dr. Fisher

“There is by no means a consensus in the academic community that ‘social media,’ or even particular social platforms are harmful to mental health in a general sense and [we] need much better data to be more sure about these links, and even more so to understand which direction the causal order flows,” Dr. Fisher concluded.