What is 'sad nipple syndrome' and what causes it?

The Guardian explains 'sad nipple syndrome', a term for sudden bursts of anguish or homesickness that people are searching for explanations of. The single item available does not give a confirmed medical cause.

Timeline

1. 3 Nov, 17:00 UTCGuardian explainer on sad nipple syndrome

Top sources

• ‘The nipple touch of doom’: what is sad nipple syndrome and what causes it?The Guardian