DB64 Food Science

Balanced Diet.

A balanced diet is a set of foods or beverages taken in the right proportions and quantities for proper growth, better health and for normal physiological processes of the body. It ensures that the cells, tissues, and organs of the body work effectively. Ojit (2016) argues that without proper nutrition, infections, diseases, poor performance, and fatigue can easily attack the body. The United Sates Department of Agriculture states that out of the ten leading causes of diseases in the world, four are because of lack of exercise and poor diet. In this essay, an outline shall be given on the components that make up a balanced diet and further provide an explanation of the various primary functions of components of food in a balanced diet (Sara 2011)

Components of food in a balanced diet.

A balanced diet is composed of six major kinds of food. These foods include proteins, carbohydrates and roughage, fats, vitamins, minerals, and water. James (1991) states that studies conducted in the 1920s revealed that most people were thin, short and suffered from many infections but their health greatly improved if they were given a diet composed of various foods such as vitamins, carbohydrates, and proteins. This served as a recipe for better health.

Carbohydrates are components of a balanced diet. According to Sara (2011), a healthy adult requires a daily intake of 225 grams of carbohydrates. Carbohydrates are obtained from rice, maize, wheat, sugarcane, fruits, milk, beet and honey. Complex carbohydrates can also be obtained from green vegetables, lentils, and beans. Carbohydrates ensure that the body is supplied with glucose that provides energy when metabolized. An excess of carbohydrates is stored in the liver in form of glycogen, which can later be converted to glucose by the hormone insulin (Sara 2011).

Fats are divided to polyunsaturated and monounsaturated fats. Sources of monounsaturated fats include olives, avocado and nuts .The primary sources of polyunsaturated fats are fish and seafood. Saturated fat and trans fat are harmful to the health. They increase chances of heart disease. According to Sara (2011), daily intake of fats should be limited to 16 grams. Fats provide the body with twice the amount of energy, which carbohydrates provide. Furthermore, they help the body synthesize vitamin D. Excess fat is stored in the liver as adipose tissue and this is used as the reserve food material (Sara 2011).

Proteins are made up of amino acids. Sources of proteins include plant sources such as beans, peas and groundnuts. The best sources of animal protein include milk, fish, eggs and lean meat. All these sources of protein provide the body with the nine essential amino acids. An adult requires a daily intake of 50 grams of proteins. Proteins contribute to the normal chemical balance and chemical reactions in the body. In addition to that, they are needed for body growth and repair. A deficiency of proteins leads to a disease known as Kwashiorkor and Marasmus, signified by impaired growth (Healthy Living n.d)

Vitamins are important dietary components, based on their solubility; vitamins are classified into those that are soluble in water or fats. Vitamins soluble in water include vitamins B and C. Vitamins soluble in fats include vitamins A, D, K and E. Sources of Vitamins include liver, milk, eggs and meat. Vitamin C, ascorbic acid, it is obtained from citrus fruits such as oranges and tomatoes. The skin when exposed to sunlight and from fish, milk, and egg produces Vitamin D. Moreover, they are required in the balanced diet because they are important for good vision, growth, good health, and proper digestion. A deficiency of vitamins can cause a condition of weak bones (osteoporosis), weak immune system, scurvy, cancers and premature aging (Healthy Living n.d).

The body also requires a large number of minerals. The most important minerals in the body include Iodine, Iron, Calcium, Potassium, phosphorus and Sodium. Sources of iodine include iodized salt and seafood. Sources of calcium include cheese, beans, milk and milk products. An excess of potassium in the body might lead to kidney failure. Iron is required to form haemoglobin, a protein needed in transport of oxygen from lungs to body cells via the blood .Calcium salts and phosphorus are required in teeth and bone formation. In addition to that, calcium helps in proper working of muscles and blood clotting. Phosphorus is a compound of Deoxyribonucleic acids, Ribonucleic acid and Adenosine Triphosphate (Healthy Living n.d).

The human body is entirely made up of water that is needed in diet, for example, the brain has 70 percent water. Sara (2011) recommends that a  human being should drink eight glasses of water daily. The water requirement in the body depends on the climate, age and the type of work carried out by a person. Generally, the body obtains a lot of water from various foods and from drinking, furthermore, it can also be obtained from oxidation reactions in the body. Water is a solvent; it helps in the transportation of compounds and nutrients in cells, digestion of food, regulation of body temperature in homeostasis, in excretion it assists in the removal of waste matter from the body (Sara 2011).

Roughage also plays an integral part in the balanced diet though it is not food. Sources of roughage include salads, fruits and vegetables with high skin fibre content such as cabbages, wheat also provides us with roughage .These foods contain cellulose that acts as roughage. Roughage is required in the body to allow for bowel movement and digestion. Furthermore, it assists in water retention in the body. These components are required in proper quantities and proportions to maintain the body in a perfect health, and development (Sara 2011).

Goitre.

The body needs sufficient amounts of iodine for proper functioning of the thyroid glands. Thyroid glands regulate the rate of metabolism through production of two hormones triiodinethyronine and thyroxin. Goiters become a dietary deficiency disease when the body lacks proper amounts of iodine that can be obtained in diet. The thyroid gland enlarges to produce the hormones required for basal metabolism therefore a goiter is produced. The thyroid gland, located on front side of the neck, causes the neck to swell. Goiters used to be prone in the English Midland areas; this was due to sandy soil that was present in that region. Soil in the region had a sandy texture and this kind of soil as compared to clay soil tends to be low in iodine. Cattle reared in the English Midland areas and areas near major river systems are goiter prone (Marcus 2017).

Scurvy

A prolonged severe deficiency of ascorbic acid (vitamin C) causes a disease known as scurvy (Peter 2017). The disease manifests in the body by allowing for a defective growth of osteoblasts, odontoblasts and fibroblasts due to breakdown of cement substances that lie intercellularly. Consequently, this damages the mechanisms of collagen synthesis. Signs of the disease include hemorrhagic gingivitis that affects the interdental papillae, bone lesions, sub-periosteal hemorrhages and petechial hemorrhages on the feet. Cerebral hemorrhage can lead to a sudden death (World Health Organization 1999) Scurvy results from a poor diet that lacks fruits and vegetables; this is evident in famine areas and low-income countries (Fredrick 2009).

Scurvy was a common disease that sailors had when they were in their sea voyages, in the fifteenth and the sixteenth centuries, scurvy was recognized as a serious disease. (Lynne 2017).These class of people were affected since they were away from the mainland and therefore they lacked access to fresh foods such as vegetables and fresh fruits. The British Navy had a practice of providing members of its forces with citrus fruits and limes in order to prevent the occurrence of the disease, this was before the advent of vitamin research. Ascorbic acid is very essential in the healthy upkeep and formation of intercellular materials; it is likened to cement that binds tissues and cells of the body (Ashkan and Craig 1994).

Polysaccharides are built from simple products, the monosaccharides. Polymerization is the process that involves formation of polymers through linking of monomers in several ways. Polysaccharides are built from monosaccharides with a form of (CH2O) N=n, n=3 . They  contain one or several monosaccharides that have functional groups removed. Both polysaccharides and monosaccharides are sources of energy but in different forms.  A study of nature of proteins reveals a relationship between protein conformation and amino acid side chains. The essential nature of an amino acid is its side chain. Amino acids are connected to each other by peptide bonds to form polypeptides (proteins). Polypeptides fold into specific proteins conformation based on the interaction between amino acid side chains (Nature Education 2014).

                                       

An amino acid structure.

References:

Ashkan, JG & Craig ,E 1994, ‘Scurvy’, Journal of American Academy of Dermatology Vol. 30. Issues 5, Part 2 ,Page 881-883..Elsevier inc .

Fredrick, MB 2009, Scurvy. Available from: https://www.researchgate.net.publication/2822527883. [6 August 2017].

Health Living n.d, 6 Components of nutrition. Available from: https: //healthylivingeating.s.fgate.com.[5 August 2017]

James TP, 1991, New concept of a balanced diet, World Health, pp 5-7.

Lynne, G 2015, Scurvy. Available from:https://www.emedicine.edscaped.com/article.[6 August 2017].

Markus, M 2017, Goitre: Causes, treatment, and symptoms. Available from: https://www.medicalnewstoday.com. [4August 2017]

Nature Education 2014, The relationship between amino acid side chains and protein conformations. Available from: https:// www.nature.com/scitable/content.99.11.[6 August 2017]

Ojit, O 2016, What is a balanced diet. Available from:https:// www.stydyhaba.com .[5 August 2017].

Peter, C 2017, Scurvy, Causes, Symptoms and Treatment. Available from: https:// www.medical newstoday.com[6 August 2017].

Sara, D 2011,What is a balanced diet? Available from:https:// www.leeds.ac.uk/yanya/science and nutrition. [4 August 2017].

William, CL 2016, Scurvy. Health Grade Operating Company.

World Health Organisation 1999, Scurvy and its prevention in major emergencies.pg 1-4.