I don't think I actually put this together until I read your comment. My actual diagnosis came just after I went off keto after having been doing it pretty steadily for about 3 years. I wonder now if the reason I noticed the symptoms of lack of focus more prior to seeking help and my diagnosis now was because it was better controlled while I was on keto and in ketosis.

I know looking back I still had symptoms. I can remember days during those 3 years just sitting in the office and realizing I had not gotten a single thing actually done and it was mid-afternoon already. But also had stretches of incredible productivity also.

Thanks for the prompt - been considering going back on keto, one of the reasons I went off is the mixed scientific evidence for its efficacy over other diets (not specifically for weight loss, just diet in the context of "way of eating") and some warnings about the lack of long-term study data because it's so hard for individuals to stay on long term. But this gives me another data point to consider and something to watch if I do try it again.