I have been taking whey protein for a while and had pretty good results. I have been having brain fog after breakfeast lately and I think it may be the whey causing it. I am going to elimintate it to see if this is the problem. I read that whey protein may release insulin. This is bad for a hypoglycemics right?
I'm not sure if that theory is true, though I have heard it. The problem may be that you're giving your body so much protein at once it's hard to process. It taxes the liver, which is essential in glucose processing.
If your whey protein is sweetened and/or flavoured then it will almost certainly be the cause of your problem. I used to have a similar problem of brain fog and the start of a hypo attack about 30 mins after drinking some (although it was after exercise and on an empty stomach).
Get unsweetened and unflavoured natural whey, or perhaps better still remove it from your diet completely if you can.