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Carbohydrates Today I would like to go a little further than the normal talk about the nutrients essential to our survival. Yes we all, more or less, know what carbohydrates or fats or vitamins or minerals are but do we really understand how they work and what do theyactually do in our body? Shall we start exploring? What are and why do we need CARBOHYDRATES? Without carbohydrates, even the process of digestion could not occur, as it needs the energy provided by carbohydrates. Without carbohydrates we would not be able to think or move and our heart couldn't beat. Whether it be digestion, circulation, thinking or walking, all life activities are dependent upon carbohydrates. When insufficient carbohydrates are available from the diet, the body converts fat reserves to carbohydrates for its use, and amino acids are utilized as carbohydrates instead of being used to make body protein. Carbohydrates provide fuel ( energy ) for the body. These rganic,( carbon-containing ) compounds are an integral part of both plants and animal life. Carbohydrates are made of 3 elements, carbon, hydrogen and oxygen. Carbohydrates along with proteins and fats comprise the major components of living matter and are used for maintenance of cellular functional activities and as reserve and structural material for cells. Carbohydrates are formed by green plants in the process of photosynthesis. In photosynthesis, plant chlorophyll, plant enzymes, sunlight, carbon dioxide from the air and mineralized water from the soil combine and, in a complicated process, synthesize carbohydrates. Humans obtain their carbohydrates needs most efficiently from the plant world. Carbohydrates are also known as SACCHARIDES, and are classified according to numbers of single carbohydrate molecules in each chemical structure. Carbohydrate compounds having just one carbohydrate molecule are called MONOSACCARIDES, compounds with 2 carbohydrate molecules are called DISSACHARIDES and those compounds containing more than 2 carbohydrates are named POLYSACHARIDES. All carbohydrates either are Monosacharides or can be hydrolyzed ( broken down ) into 2 or more Monosacharides. Monosacharides and disaccharides can be grouped together and compared with the polysaccharides. This can be done because mono- and disaccharides have certain things in common. They are both water soluble, and they both have a sweet taste and a crystalline structure, they are called SUGARS and all share the suffix -ose, meaning sugar. Polysaccharides, in contrast to mono- and disaccharides, are insoluble in water, do not taste sweet and do not form crystals. Also, they do not share a suffix and have no group name ( such as sugars ) They are sometimes called starches, but this is technically incorrect because there are many other classifications of polysaccharides besides starches ( cellulose and glycogen being two and dextrin being another ) MONOSACCHARIDES are the only sugars that can be absorbed and utilized by the body. Disaccharides and polysaccharides must be ultimately broken down into Monosacharides in the digestive process known as HYDROLYSIS. Only then can they be utilized by the body. Three Monosacharides are particularly important : glucose, fructose & galactose. GLUCOSE, ( also known as dextrose or grape sugar ) is the most important carbohydrate in human nutrition because it is the one that the body uses directly to supply its energy needs. Glucose is formed from the hydrolysis of di-and polysaccharides, including starch, dextrin, maltose, sucrose and lactose: from the Monosacharides fructose largely during absorption; and from both fructose and galactose in the liver during metabolism. Glucose is found in the bloodstream and provides an immediate source of energy for the body's cells and tissues. Glucose is also formed when stored body carbohydrates ( glycogen ) is broken down for use. In the plant world, glucose is widely distributed. It is found in all plants and in the sap of trees. Fruits and vegetables are wholesome food sources of glucose. FRUCTOSE, ( levulose or fruit sugar ) is a Monosacharides and is similar to galactose. These 2 simple sugars share the same chemical formula, however, the arrangement of their chemical groups along the chemical chain differ. Fructose is the sweetest of all the sugars and is found in fruits, vegetables and the nectar of flowers, as well as in molasses and honey. GALACTOSE differs from the other simple sugars, glucose and fructose, in that it does not occur free in nature. It is produced in the body in the digestion of lactose, a disaccharide. Well, I think that this is enough fancy words and mind-boggling chemistry for one day. Next week we will discuss Disaccharides, Polysaccharides and the role of carbos in our body See you then, The Crazy Nut team.