A diet is correct and balanced when, on a daily basis, a series of suggestions and rules relating to the quantity, quality, and variety of foods eaten are followed [1]. The daily energy intake must be adequate for calorie consumption, and all the nutrients that allow you to derive health benefits must be present in a diet. There is no food that can be said to be truly complete (if we exclude breast milk for babies up to 8-12 months). The simplest and safest way to be able to assimilate, in the right quantities, all the nutrients necessary for the proper functioning of our body is to vary the foods eaten and combine them in the most appropriate way. The body contains almost all the nutritional elements that we find in food, the nutrients, that are divided into macronutrients (carbohydrates, lipids, and proteins) and micronutrients (vitamins and minerals). Macronutrients give energy, while micronutrients do not give energy, but they are necessary for biological functions [2,3]. Alcohol is a particular macronutrient that gives energy, but it is not necessary for a healthy diet.Water, despite being an indispensable element for many functions (and the composition itself!) of the human body, is not considered a nutrient.To follow a balanced diet, it is advisable to take the correct quantities of macroand micronutrients and that the daily calorie intake is divided into specific proportions. This means that 15% of the daily calories should come from protein, 25-30% from lipids, and 55-60% from carbohydrates.