Answer
A nutrient is any chemical substance which is ingested and utilized by the body for growth, repair and maintenance.
Nutrients are classified as essential and non essential, but there are two definitions of essential nutrients used by nutritionists, dieticians and other people concerned with food and nutrition. The one used here is the following: "Essential nutrients are nutrients that the body is incapable of synthesizing- or of synthesizing in adequate amounts to support health." These include most vitamins, eight (or 9) of the amino acids, and two or three of the fatty acids. These nutrients must therefore be obtained from food/diet.
Essential nutrients on most lists include, minerals, 13 vitamins, 8 (9) amino acids and 1-3 fatty acids
The Essential amino acids. Twenty amino acids are usually found in our cells ; the 9 that we cannot make are are histidine, valine, isoleucine, leucine, phenylalanine, threonine, tryptophan, methionine, and lysine-- infants and adolescents cannot make enough arginine.
Work Step by Step
Essential Vitamins:
There are 13 vitamins that are required for good health; of these only two can be synthesized in the body-- often not in adequate amounts. The vitamins that we can make are Vitamin D, and biotin.
The essential vitamins are A, C, E, K, B1, B2, B3, B6, B12, pantothenic acid, and folic acid. Most people also need supplemental Vit D, and biotin.
Two fatty acids that are often taken as dietary supplements; these are alpha-linolenic acid, linoleic acid. They are classified as essential fatty acids.
