It sounds like a silly question, but I'm wondering. For example, diet advisors say to never skip breakfast. So what satisfies that requirement? A certain amont of calories? Volume? A mix of carbs/sweets/proteins that sparks a certain digestive response? Is is physiology, chemistry, psychological?
I can see how eating a big bowl of oatmeal, for example, will both fill the tummy and also require some long term digestion. But what if I have a glass of 2% milk and some yogurt? What about 2 glasses of water and a nutirtion bar? Are those too "weak" to bump the metabolism?