Mark Zuckerberg’s testimony this week in a landmark social media case revealed not just how the Meta CEO has thought about youth social media addiction—but also his view on the impact of Instagram on the self-confidence and well-being of young girls.

The case is brought by a plaintiff called called Kaley G.M., or K.G.M., against Meta and Google. Now 20, she says Instagram and YouTube were addictive, which led to personal injury and other harm. She opened her Instagram account at age 9. TikTok and Snapchat have faced similar claims, but settled out of court.

Most attention in the lead-up to the trial was on social-media addiction in young people, as well as the absolute worst of its impact, like teens who died by suicide after viewing content about self-harm. The trial is taking place in California, a state that has tried to better regulate the tech and AI giants based there after failing to do so during the initial rise of social media.

Watching the case, what stood out to me as well was the exchange about Instagram beauty filters. The plaintiff said beauty filters contributed to her body dysmorphia. The filters allow users to alter their faces to look more attractive or like they’ve had plastic surgery procedures. For a young girl dealing with insecurities, the ability to look completely different on Instagram could make her feel inadequate when she looks in the mirror in real life—and make her feel like she needs those cosmetic procedures outside of the app too.