Do not skip breakfast; if you do, your blood sugar levels will be so low by mid-morning that you are likely to become snappy from hunger - and then succumb to a quick fix from a sugary snack. Keep your blood sugar levels, and hence your energy levels, more stable by eating three meals a day, making sure you eat adequate amounts of protein (it slows down the rate at which the carbohydrate you eat is digested, so keeps you feeling fuller longer), and snack on fruit, seeds and nuts - all of which have huge nutritional benefits - rather than chocolate, crisps or biscuits.