I've been trying for years to figure out exactly what causes it. Searching online gives you hundreds of possible causes, for ages I thought it was gluten in my diet, sugar, anxiety causing it, and to some extent I think all of these do affect it.
Recently though I've noticed that sleep might be causing it, specifically breathing through my mouth when I sleep causes me to have a foggy feeling throughout the day, so I'm working on trying to breathe through my nose for the whole night now.
I've been trying for years to figure out exactly what causes it. Searching online gives you hundreds of possible causes, for ages I thought it was gluten in my diet, sugar, anxiety causing it, and to some extent I think all of these do affect it.
Recently though I've noticed that sleep might be causing it, specifically breathing through my mouth when I sleep causes me to have a foggy feeling throughout the day, so I'm working on trying to breathe through my nose for the whole night now.
Hope this helps!