Sweet or savoury? It's commonly thought that the answer to this question lies in the first food that you were given to try as a baby. If it was a savoury nibble, like some mashed potato, then you will supposedly be more inclined to reach for the cheese and crackers at the end of a meal. If your first food was sugary, like mashed banana, then your sweet tooth is supposed to hold more sway. While there is no hard science to back up this old wives' tale, it is true that some people are just naturally more inclined to all things sugary and, for a percentage of the population, this can move beyond a simple sweet tooth.
Your body needs food as fuel and, when it's in a slump, you will primarily crave sugar and carbohydrates to refill the glucose stores that are burned up through everyday life.