well, msg is just a flavour enhancer derived fom seaweed but is found naturally in foods too (tomatoes, mushrooms, chicken, cheese). Some people are reported to suffer from migraines and/or other symptoms but it's widely accepted as generally non harmful. Like I said, I've found it in the oriental flavoured crisps.
It's helped the vividness and the recall of my dreams greatly over the last week. There are quite a few reports over the web that agree that it does affect dreams and dream recall but I've no idea why.
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