Social media adverts must clearly state the use of manipulated images because of the risk to people's mental health, campaigners have said.

Postgraduate student Lara Philippart, from Swansea, said she began a petition after social media caused her anxiety about her body.

The 24-year-old began researching the topic as part of a master's degree.

"I realised the extent of which people are affected by social media," she said.

She feared people were "under-eating" in a bid to look like unachievable images, created with filters, and it struck her something "needs to be done".