Nutrition - Essay Example

Download file to see previous pages The Six Classes of Essential Nutrients Proteins, carbohydrates, water, lipids, minerals, and vitamins are the key essential nutrients for the human body. Proteins carbohydrates, water, and lipids are classified as macronutrients, while minerals and vitamins are classified as micronutrients (1). Insel et al, 2011, p.230, define proteins as “large molecules made up of amino-acids joined in various sequences”. Thus various kinds of proteins are present in the human body in various shapes. Based on their shapes the several kinds of proteins have specific roles within the human body. Some of them are enzymes, and speed up the many chemical reactions within the body essential to its survival. Some others act as hormones. Hormones may be viewed as chemical messengers within the human body. Yet other hormones go into the makeup of the antibodies of the human body to protect the human body from foreign substances and pathogens. Some other proteins act as pumps within the body to maintain fluid balance. In this balance maintaining process they pump molecules across cell membranes and attract water. The acid base balance in the body is maintained by the action of proteins through the taking up or releasing of hydrogen ions, depending on the need. Finally, proteins act as transporters for many key substances like oxygen and the micronutrients to the targeted cells all over the human body. The essential nature of proteins to the human body is thus clear (2). Insel et al, 2011, p.146, define carbohydrates as “organic compounds that contain carbon (C), hydrogen (H), and oxygen (O) in the ratio of two hydrogen atoms and one oxygen atom for every carbon atom.” The main role of carbohydrates in the body is to act as a fuel for the cells in the human body. Even though the human body can use fats also for energy purposes, carbohydrates are the preferred source of energy, particularly for the brain, red blood cells, nervous system, fetus, and placenta. Carbohydrates also contain fibres that make it easier for the passage of stools through the digestive system (2). Water is absolutely essential for the survival of the human body. The water content in the human body is responsible for up to 75% of the weight of the human body. The importance of water to the human body lies in it being a very good solute. In the human body water carries several dissolved minerals in the form of electrolytes. These electrolytes are maintained at a constant balance. The very existence of cells in the human body depends on the maintenance of the right balance of these electrolytes in water (2). Insel et al, 2011, p.182, describe lipids as “a broad range of organic molecules that dissolve easily in organic solvents like alcohol, ether, and acetone, but are much less soluble in water.” Three main types make up the lipids, which are triglycerides, phospholipids, and sterols. Lipids are an energy source for the body and when stored in the body as fat act as energy reserves in the body for use when there is a deprivation of carbohydrate supplies to the body (2). Ball 2004, p. 8, defines vitamins as “a group of organic compounds which are essential in very small amounts for the normal functioning of the body.” Vitamins as required for nutrition in the human body are thirteen in number and classifies into water soluble vitamins and fat soluble vitamins. The water soluble vit ...Download file to see next pagesRead More