They also say that we them for different purposes:
We need carbohydrates because:
* Carbohydrates are needed for the central nervous system, the kidneys, the brain, the muscles (including the heart) to function properly..
* Carbohydrates are important in intestinal health and waste elimination.
Proteins make up the structural foundation of the cells, tissues, and organs. Proteins are made up of smaller building blocks called amino acids.
We need protein for:
* Tissue repair
* Immune function
* Making essential hormones and enzymes
* Energy when carbohydrate is not available
Fats are complex molecules composed of fatty acids and glycerol. The body needs fats for growth and energy. It also uses them to synthesize hormones and other substances needed for the body's activities (such as prostaglandins). Fats are the slowest source of energy but the most energy-efficient form of food. Although fats have received a bad reputation for causing weight gain, some fat is essential for survival we need fat for:
* Normal growth and development
* Absorbing certain vitamins ( like vitamins A, D, E, K, and carotenoids)
* Providing cushioning for the organs
* Maintaining cell membranes