How kind of you to respond, thank you Kathleen! I have been having eggs and oatmeal made with coconut milk for breakfast. A big salad (raw spinach, avocado, tomato, cucumber) with salmon for lunch. And for dinner, some form of meat or fish, with lots of veggies, and a very small amount of brown rice, quinoa, or a small potato. No snacks during the day, but a little Greek yoghurt at night, which I find helps me sleep. (I've tried having a potato, but I wake up in the night with low blood sugar if I do.) I have no sugar, no caffeine. I take a multivitamin that is particularly high in B complex, and extra Vitamin D in addition.

I have been journalling, and that has helped me to pinpoint that when I do have a meal with no obvious carbs (apart from veg), I don't get fatigued. So I tried that for a few days, but I can feel my mood slipping very fast downhill.

I seem to be most sensitive to carbs in the morning - just having 1 oatcake with my eggs (which is about 7g carbs) is enough to make me sleepy all day.