Some of the body's most essential nutrients are every bit as important as carbohydrates, fats, and protein. These important nutrients are vitamins, minerals, and water. All the food you eat includes all these essential nutrients. This is what keeps your body alive. Vitamins are compounds that help regulate many vital bodily processes, including the digestion, absorption, and metabolism of other nutrients. Vitamins are classified into two groups: water-soluble and fat-soluble.

Proteins are made up of amino acids and different proteins contain different proportions of the various amino acids.

There are in all 23 amino acids in food proteins. Out of these, there are 10 that the human body cannot synthesize: arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophane and valine. These are, therefore, called essential amino acids.
The body must be supplied with the requisite amounts of these amino acids through food. The rest of the amino acids can be synthesized by the body from these.