The gut is being called "the second brain" (even though it was our first brains as we evolved) because of many things, but a big one is that it is so closely tied to our brain and communicates with it constantly. What you eat most certainly impacts your digestive tract and microbiome which will most certainly impact your brain.
If the gut is inflamed, your brain will be inflamed, which will cause brain fog. Food sensitivities will also cause brain fog for similar reasons but also if there are increased antibodies to those foods and those antibodies are finding similar structures in your brain and attacking those. This is common with gluten.
I'd suggest you try to remove the most common trouble foods for a few weeks and see if your brain fog lifts:
-Dairy (though we could potentially fix a dairy sensitivity)
and I'd add all grains to keep inflammation down
in the meantime eat:
- Slow cook broth (3 hour meat & bone broth) I can give you a recipe
- fermented veggies (sauerkraut, fermented pickles, kimchi)
- well cooked veggies and meats
- Lots of high quality and varied fats (butter, ghee, olive oil, coconut oil)