Nutrients are the substances our bodies need to function and are almost always found in food, except for a few special cases (e.g. vitamin D which is obtained from sunlight).
“Nutrients” are not “foods”: a given nutrient is found in different foods, and each food contains different nutrients.
We often say “I had carbohydrates for lunch”, but this is incorrect: you eat certain foods that contain carbohydrates. No food contains only one nutrient.
If you eat grains, you are taking in carbohydrates, certainly, but also protein, fiber, vitamins, minerals. And if you eat legumes, you take in protein, but you also take in carbohydrates, etc.
Our bodies obtain nutrients from the foods we eat every day, through the digestive processes and chemical reactions that take place in the body. These substances are essential for the maintenance of life, growth, and renewal of the body’s structures.
Nutrients can be divided into macronutrients and micronutrients:
- macronutrients are carbohydrates (carbohydrates), proteins, and fats (lipids);
- micronutrients are minerals, vitamins, and phytocompounds.
Fiber and water should also be considered as important components of the diet, even if they do not provide calories.
Nutrients can also be classified according to their function:
Energy – are the nutrients that our bodies use to derive energy for their vital functions.
The main nutrients used for this purpose by the body are carbohydrates and lipids.
Proteins can also be used for energy purposes, but that is not their main function.
Plastics and structural – provide the material for the growth and replacement of cells in our organs and tissues; role is played primarily by proteins, but also by lipids.