YouTube’s algorithm promotes medical misinformation in a number of languages, a BBC investigation has found. Searching YouTube across 10 languages, the BBC found more than 80 videos containing health misinformation - mainly bogus cancer cures.

Ten of the videos found had more than a million views. Many were accompanied by adverts. The BBC asked Professor Justin Stebbing, a cancer expert at Imperial College London, to have a look at some of these claims.

In a statement YouTube said: "We have taken a number of steps to address this including showing more authoritative content on medical issues, and removing ads from videos that promote harmful health claims. Our systems are not perfect but we're constantly making improvements, and we remain committed to progress in this space."