Actually, I find it to be quite the opposite.

Grains actually make me dopey and if I eat too many, I will get a kind of 'mood crash'.

It seems similar to what the guy said on, "Supersize Me". How, if he didn't eat for a while, there would be 'withdrawal symptoms', like headache, a downswing and cravings for the causative food.

My son also is affected by grain this way... so I'm thinking it's a genetic thing.

Oddly, though the world seems to really promote wholegrains, we've found that they are the worst culprits for causing depression. (Gluten grains are an absolute 'no' for us but even wholegrain rice that can cause carsickness in my son, can also bring us down a notch or two in energy, brain-function and mood.)

We have not noticed the same with fruit or veggies... so I don't think it's a 'carb' thing so much with us as a 'grain/starch' thing. (Potatoes can make us headachey and have joint pain too.)