The Body Clock Diet looks at circadian rhythm. With regard to diet, it explains that carbohydrates promote sleep, by raising insulin levels, and at night blood glucose runs slightly higher to enable replenishing glycogen reserves.
Protein on the other hand 'burns dirty', which promotes consciousness.
From this the recommendations are to have protein earlier in the day and less carbohydrates.
However, when we've woken in the morning, our hormones are working to waken us and keep us awake, so we may not need much protein for breakfast either?
Compare this with the Zone Diet that advocates having the same balance of macro-nutrients at every meal.