Breakfast determines how even your energy level is throughout the day and is necessary if you want to meet both your micro and macronutrient targets for the day. This is relevant for your immune system, your physical and your mental development as well as the recovery and repair process of both. In addition, those who don't have breakfast suffer a much higher risk of developing diabetes at a higher age, and it's usually the meal when we get our daily need of stomach bacteria (yoghurt), fibre (good bread or cereal) and potassium (yoghurt and bananas). All are vital for the immune system. I could go on.