#BBCtrending: The rise of the #nomakeupselfie trend
20 March 2014 Last updated at 20:08 GMT
Since Tuesday social media timelines across the UK have been bombarded with the #nomakeupselfie hashtag.
The trend has been most popular on Facebook. A page dedicated to it called 'No Make Up Selfie for Cancer Awareness' has over 231,000 likes.
Anne-Marie Tomchak of #BBCtrending explains how the trend became so popular and what wearing no make-up has to do with cancer.