The Effects of Food on the Body

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Fats are either saturated or unsaturated depending on the way the carbon and hydrogen atoms are arranged. Saturated fatty acids are formed when a hydrogen atom bonds to both sides of each carbon atom to form a vertical chain. This shape enables more chains to bond closely together resulting in fats being solid at room temperature. Unsaturated fats, however, do not have two hydrogen atoms connected to each carbon atom. Some chains only have one hydrogen atom while the carbon atom connects with a double bond to the adjacent carbon atom horizontally. Because the molecules are not packed tightly together the fat is liquid at room temperature. Hence the physical differences between fats and oils (Lycett).

There are two forms of unsaturated fats (oils): monounsaturated fatty acids and polyunsaturated fatty acids. Monounsaturated fatty acids are sometimes called omega-9s because the double bound is formed in the ninth position of the fatty acid chin. Polyunsaturated fatty acids are formed when there is more than one double bonded link in the fatty acid chain. Polyunsaturated fatty acids are subdivided in to omega-6 and omega-3. In each of these omega groups there is an essential fatty acid that the body cannot synthesize. These essential fatty acids

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are Linoleic acid from omega-6 oils and alpha-linilenic acid from omega-3 oils. From these two fatty acids, the body can generate all other fatty acids that it needs (Lycett).

The body uses fat for cellular development, chemical regulations and energy. Throughout the body, especially the brain and nervous system fat is used to form all the cell membranes. It also forms an insulating layer beneath the skin which surrounds and protects the skeleton structure and vital organs. This layer called adipose tissue or body fat is formed when fat is stored for future energy consumption. Adipose tissue is also used to regulate body heat (Tull). Another major function of lipids is for the transportation, breakdown and excretion of cholesterol. Cholesterol is the main component of cell membranes, blood plasma and makes up other substances such as steroid hormones like estrogen and testosterone, vitamin D and bile acids (Houghton Mifflin company). Fat is also the medium through which fat soluble vitamins and antioxidants are transported around the body (Lycett).

More specifically, saturated fatty acids are responsible for increased levels of cholesterols in the body including low density lipoprotein (LDL) more commonly known as the ‘bad’ cholesterol. On the contrary, monounsaturated fatty acids reduce LDL in the blood while it increases and maintains the required level of high density lipoprotein (HDL). As a result, monounsaturated fatty acids are considered to be ‘good’ cholesterol. The omega-6 and omegas 3 oils are converted into longer chains of fatty acids that are precursors for immune and inflammatory responses. In addition, they also play a vital role in the development of the brain, nerves and retina in fetal development and early life. Fats also supply the body with more energy than proteins and carbohydrates combined. In light of this, fats perform the three main functions of macronutrients in the body (Lycett).

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Fats and oils are obtained in the diet from both animal and plant sources. For example, saturated fats can be found in meat and meat products, whole milk and dairy products, pastries, fried foods, coconut and palm oil. Monounsaturated fats can be found in, olives, avocados, peanut, almonds and cashew nuts and their oils. Fishes like, salmon, mackerel and trout as well as walnuts, flax seed and their oils are sources of omega-3. The oils, seed and nuts of sunflower, wheat germ, sesame, soybean, and corn are also sources of omega-6 fatty acids (Laberge). Fats in the diet can either be visible, meaning noticeable like butters, cooking oils and fats on meat. Or like in, nuts, avocado and prepared food fats can be invisible because they are an ingredient in the food or not noticeable (Tull).

Although protein and fat supply the body with some form of energy, the main source of energy in the body is carbohydrates. Carbohydrates supply the body with calories that are neede d to keep active and are the primary source of energy for the brain. (Laberge). They are also involved in the construction of body organs, nerve cells but more importantly, the genetic transcription for identifying blood types. Carbohydrates can either be simple or complex. Simple carbohydrates are water soluble and provide a quick source of energy. They are grouped as monosaccharide or disaccharides: single unit or two unit sugars (Jegtvig). Complex sugars on the other hand are not water-soluble and provide a slower but more sustainable release of energy (netdoctor.co.uk). They are made up of multiple sugar molecules and are classified as polysaccharides. Despite their varying quantities of sugar molecules, carbohydrates are all made up of carbon, hydrogen and oxygen atoms in a ratio of 1:2:1 (American Heritage® Medical Dictionary).

Carbohydrates are found as sugars, starches and fibers in the diet mostly from plant-based foods. The basic component for all carbohydrates is a monosaccharide. Glucose is one of the

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three types of monosaccarides and is found in ripe fruits and some vegetables such as onions and beetroots. Glucose is the main form of sugar used by muscles to move and other organs such as the brain to function. During digestion all other carbohydrates are converted into glucose. The other monosaccharides are fructose and galactose. Fructose also know as fruit sugar is found chiefly in fruits, plant juices and honey while galactose is found in the milk of mammals (Jegtvig).

There are also three types of disaccharides which are formed by combing another simple sugar with glucose. Maltose is formed by the combination of two glucose molecules. It is known as malt sugar and is found is cereals such as barley during germination. The combination of glucose and fructose forms sucrose or table sugar. This is the most common type of sugar used in food preparation. It is acquired from refined cane or beets. It can also be found in other fruits and vegetables. Lastly, lactose which is a combination of glucose and galactose is commonly known as mile sugar. It is found in the milk of mammals to provide babies with a source of energy.

Polysaccharides are made up of various amounts of monosaccharide molecules and are tasteless. There are five forms of polysaccharides.