YouTube will remove content that promotes “cancer treatments proven to be harmful or ineffective” or which “discourages viewers from seeking professional medical treatment,” the video platform announced today. The enforcement comes as YouTube is attempting to streamline its medical moderation guidelines based on what it’s learned while attempting to tackle misinformation around topics like covid-19, vaccines, and reproductive health.

Going forward, Google’s video platform says it will apply its medical misinformation policies when there is a high public health risk, when there is publicly available guidance from health authorities, and when a topic is prone to misinformation. YouTube hopes that this policy framework will be flexible enough to cover a broad range of medical topics, while finding a balance between minimizing harm and allowing debate.

In its blog post, YouTube says it would take action both against treatments that are actively harmful, as well as those that are unproven and are being suggested in place of established alternatives. A video could not, for example, encourage users to take vitamin C supplements as an alternative to radiation therapy.