I can totally believe that diet makes a difference, because eating low carb and keeping my hypoglycemia in control definitely helps my concentration (and I’m the queen of spacey-ness). I used to think supplements were a scam, and then I realized that the Ginger capsules I tried for motion sickness made my brain fog diminish drastically. I couldn’t believe it, tried on and off. It’s like magic. That’s what got me interested in the brain/body chemistry which led me to the book I mentioned above.