There is a lot of truth to this old saying, with a little modification. First, you need food for energy during the day, so it does not make sense to eat a third of your day's food in the evening. Also, it is definitely not a good idea to go to bed still digesting your dinner. As a general rule, eat dinner early and leave at least two hours before going to sleep. Similarly, we are not designed to eat as soon as we wake up. It is better not to eat until you are totally awake, perhaps an hour after waking. Breakfast is the important meal of the day and, as such, should be substantial (say, a boiled free-range egg with wholemeal toast, or seed-rich muesli with yoghurt, milk or soya milk). Having said that, if you are eating three meals a day, plus two pieces of fruit as snacks in between, no meal need to be vast. It is better to leave a meal feeling satisfied, not stuffed.