I have no idea. They could happen at any time and for no apparent reason. This article seems to suggest they only happen at times of great trauma, but that wasn't my experience at all -- thankfully!
"I have no idea. They could happen at any time and for no apparent reason. This article seems to suggest they only happen at times of great trauma, but that wasn't my experience at all -- thankfully!
Diet may have something to do with it.
One food additive I could think of is MSG in Chinese food.