Does anyone have brain fog that comes on right at sunset? Any known causes? I had CFIDS for 2 years and have been better 95% for years now, but I am stuck with this weird BF that comes on at sunset. Perhaps I am a vampire (joking!). Anyone have any suggestions as to what could be causing this? I know it is not a food allergy because I have fasted for 11 days and it did not change.