Essential amino acids

Amino acids are formed of an amino group, a carboxyl group, and a side chain. Human body is unable to synthesize 9 essential amino acids. These essential amino acids must be obtained from food. The essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Such amino acids as arginine, cysteine, and tyrosine may be required in particular situations for premature babies and in people suffering from liver disease. Meat, fish, eggs, and dairy products are important sources of high quality proteins. Essential amino acids in these products can satisfy human requirements. The food proteins such as egg albumin, milk casein, and wheat gluten are digested into their constituent amino acids and then absorbed from intestine. Amino acids in the body are connected by peptide chemical bonds forming proteins such as enzymes, hormones as well as structural, transport, and contractile constituents of the body. Plant foods taken separately are less suitable protein sources. However, balanced vegetarian diets can also satisfy human protein needs if they harmonize each other with essential amino acids.

Essential fatty acids

People have particular nutritional demands for certain organic substances. Among them are essential fatty acids. The case is that human body is unable to synthesize 2 essential fatty acids called linoleate and linolenate. Therefore, these essential fatty acids must be obtained from dietary plant sources. Human body may store assimilated fatty acids or oxidize them to get energy. These essential fatty acids are important precursors of eicosanoids needed for numerous significant metabolic processes. Essential fatty acids take part in the production of phospholipids that are important constituents of cell membranes and nerve fibers. Production of some hormones also requires participation of essential fatty acids. From all these standpoints, essential fatty acids are valuable dietary substances. Vegetable oils are precious sources of linoleic and linolenic essential fatty acids. Deficiencies of these essential fatty acids may develop in patients with disordered intestinal absorption, babies fed with low-in-fat formulas, and small children consuming nonfat milk or meals low in fat.