Science

I saw people making this claim on Twitter, but the study itself doesn't make that claim—I think people are just looking at one table and going off half-cocked.

First off, it's not mentioned in the "Public Significance Statement" (which seems to be what they want laypeople to take away from the article):

Short-form video platforms such as TikTok, Instagram Reels, and YouTube Shorts are now a major part of daily life for many people. Our synthesis of 71 studies revealed that greater engagement with these platforms is associated with poorer cognitive and mental health in both youths and adults. For some health domains (such as body image and self-esteem), these associations may depend on the type of content encountered, highlighting the need for further research to inform public health strategies and platform design.

Here's the relevant portion of the discussion that talks about which platforms are used, which is in a subsection entitled "Moderators of SFV Engagement and Health" (emphasis mine):

SFV type emerged as a significant moderator of the association between SFV use and mental health, with general SFV use demonstrating stronger negative associations than TikTok-specific use. A potential explanation for this finding is that general SFV use often reflects engagement across multiple platforms, which has been associated with elevated mental health risks. For example, Primack et al. (2017) found that individuals using 7–11 social media platforms had over three times the risk of depression and anxiety compared to those using only 0–2. Accordingly, general SFV use likely reflects more diverse and frequent exposure to short-form content, including across platforms that integrate SFV features (e.g., Instagram Reels, YouTube Shorts). This broader pattern of general SFV use highlights the need to conceptualize SFV engagement beyond TikTok alone, particularly as users commonly migrate between platforms. The recent (temporary) banning of TikTok in the United States, for instance, prompted a surge of “TikTok refugees” shifting to alternatives like RedNote and Lemon8 (Australian Broadcasting Corporation, 2025). Yet “general SFV use” may also refer to a single platform, raising concerns about measurement precision. It is therefore important for research to clearly specify which platforms participants use and whether engagement spans multiple apps. As SFV features become increasingly integrated across the social media landscape, research and public health efforts should consider cumulative SFV exposure rather than focusing on individual platforms in isolation.

and just to be clear, here's what they say about the makeup of the studies:

Most studies focused on general SFV use (no specific app mentioned; 52%), with TikTok being the only specific SFV platform explored in the studies included in this review (48%)

So basically, it's saying that the "general use" measures being worse could be a result of using multiple platforms simultaneously OR that use of specific non-Tik-Tok platforms could genuinely be worse, but it doesn't sound like the general SFV studies they looked at (since this is a meta-analysis) were specific enough about app usage to draw any conclusions.