The main three are 1. glucose which is derived from starches and disaccharides 2. fructose which comes from fruits 3. Galactose which comes from milk

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1 Carbohydrates are sugars that are joined together to form polymers or simple monomers units. Foods that are high in carbohydrates include breads, pastas, beans, potatoes, bran, rice and cereals. Carbohydrates are compounds made up of carbon, hydrogen and oxygen One gram of carbohydrate provides four calories of energy; medical experts say that 60 percent of the calories you eat every day should come from carbohydrates. Our maximal carbohydrate storage is approximately 15 grams per kilogram of body weight [15 grams per 2.2 pounds]. So a 175-pound athlete could store up to 1200 grams of carbohydrate [4,800 calories]; enough energy to fuel high intensity exercise for quite some time. The recommended daily allowance of carbohydrates is 130 grams per day. However the actual intake is higher. Adult men consume between 200 and 330 g/d, while adult women consume between 180 and 230 g/d. Monosaccharide (one sugar unit) The general formula is (C H 2 O) n the major source of fuel for metabolism, they cannot be hydrolyzed to smaller carbohydrates. The main three are 1. glucose which is derived from starches and disaccharides 2. fructose which comes from fruits 3. Galactose which comes from milk Fruits and vegetables are not only great carbohydrate sources, they re also excellent suppliers of vitamins A and C and many other vitamins and minerals Natural simple carbohydrates are the best carbohydrates to include in the diet, especially if trying to lose weight e.g. apples blackberries strawberries due to the fact that they are low in simple sugars and use up a lot of energy breaking them down Sugar, which provides 16 calories per teaspoon, provides no vitamins and minerals, has been linked to the development of cavities. Oral bacteria such as Streptococcus mutans live in dental plaque and metabolize sugars into lactic acid.high consentration of this acid leads to tooth demineralization. Sugar is often wrongly name as the cause of Diabetes whereas the truth lies in the fact that the body is unable to produce any insulin(type 1) or when the body becomes insulin resistance (type 2). Disaccharides (two sugar unit) Lactose is combination of glucose and galactose digested in the small intestine Is found in milk is the least sweet sugars However galactose is not essential as it can to synthesised within the body Lactose intolerance is the inability to break down lactose which occur due to the lack of lactase or when then body completely stop producing it Maltose combination of 2 glucose molecules Brewing is the production of alcoholic beverages and alcohol fuel through fermentation Sucrose combination of glucose and fructose

2 These two sugars are broken down or hydrolyzed by the enzyme sucrase. Is found in milk fruits and vegetables e.g. is found in milk sugar cane and beet roots The prevalence of both dental caries and tooth wear increased with age. In 1997 more than one third (35 per cent) of children aged 4 to 18 years had unhealthy gums In a typical week in 1997: Four in five young persons aged four to 18 years consumed white bread, chips, savoury snacks, biscuits, chocolate confectionery and boiled, mashed and jacket potatoes. The most commonly consumed fruits among 4- to 18-year-olds were apples and pears (53 per cent of boys ; 57 per cent of girls) followed by bananas (38 per cent of boys and girls, respectively). Children and adolescents from higher socio-economic households were more likely to have eaten raw and salad vegetables, apples, pears and bananas than those from lower socio-economic households. Based on evidence for risk of heart disease and obesity, the Institute of Medicine recommends that American and Canadian adults get between 40-65% of dietary energy from carbohydrates. [5] The Food and Agriculture Organization and World Health Organization jointly recommend that national dietary guidelines set a goal of 55-75% of total energy from carbohydrates, but only 10% should be from Free sugars (their definition of simple carbohydrates). [6] Oligosaccharide Is a simple sugar containing three to ten polymer chainthat are generally component of glycoproteins or glycolipids and Oligosacchrides are often found combined to a amino acid Examples Fructo-oligosaccharides (FOS) - short chains of fructose molecules found in a lot of vegs Galacto-oligosaccharides (GOS) - consist of short chains of galactose molecules Polysaccharides Starch Stored in the muscles and livers as glycogen which are polymers of glucose linked together in branched chains. During exercise glycogenolysis occurs which is the break down of glycogen into glucose. Where glycogen depletion exceeds the replacement of glycogen storage an athlete may experience glycogen debt, extreme fatigue to the point that it is difficult to move. it can however be delayed by a carbohydrate loading before the competition.

3 How glycogen can be seen as inefficient as it only yields a small amount of energy resulting in a few hours of energy. Starch goes not have a sweet taste however it does yield the same energy as sugar. Due to its lack of taste starchy foods are one of the first foods that are reduce once a person is affluent enough to have the choice Non-Starch Polysaccharides NSP are components of plant cell walls for example cellulose. However the human body does not produce the enzyme cellulase needed to break down cellulose. Therefore passes through the digestive system undigested. NSP also includes complex wood material and lignin. NSP slows down the rate of digestion of glucose. In refined foods the dietary fibre is removed during processing e.g. wholemeal flour contains fibre but white flour does not. Unrefined foods have high fibre content. The more processing is carried out on food the less fibre it contains. The Recommended Dietary Allowance (RDA) of fibre is now 30g per day, which can range according to age and sex from 21 to 38 g daily Fibre These include constipation, haemorrhoids (piles), diverticular disease and cancer of the colon or large bowel. Soluble fibre helps to decrease the rate of glucose absorption in the blood system which works towards stabilising blood sugar levels. The risk of heart disease is also reduced as fibre helps to lower blood cholesterol levels. Good sources of soluble fibre include peas, sweet potatoes, barley and oat wheat Non-soluble Fibre is essential for healthy bowel function and appears to reduce the risk of colon cancer. Benefits One gram of carbohydrate provides four calories of energy Our maximal carbohydrate storage is approximately 15 grams per kilogram of body weight [15 grams per 2.2 pounds]. So a 175-pound athlete could store up to 1200 grams of carbohydrate [4,800 calories]; enough energy to fuel high intensity exercise for quite some time. The Position Statement from the Dietitians of Canada, the American Dietetic Association, and the American College of Sports Medicine, Canadian Journal of Dietetic Practice and Research in the Winter of 2000, 61(4): Side Effects Excessive carbohydrates can cause an increase in the total caloric intake, causing obesity.

4 Deficient carbohydrates can cause a lack of calories (malnutrition), or excessive intake of fats to make up the calories Most research on carbohydrate recommendations for endurance athletes has been based on male subjects. Lower recommendations for carbohydrate (g/kg BW) intake in females may be appropriate because research based on female endurance runners indicates that females utilize less carbohydrate and more fat than males at any given intensity of endurance running Recommendations for refilling muscle and liver glycogen stores in a 150 lb person after exhaustive endurance exercise includes consumption of between grams carbohydrate within 24 hours. What does 500 grams of carbohydrate look like in food? Food Amount Carbohydrate (grams) Corn flakes 2 cups 52 1% milk 2 cups 23 Yogurt 1 cup 42 Orange Juice 1 cup 27 Banana 1 med 27 Bagel 1 med 38 Jam 1 Tbsp 13 Bread 2 slices 24 Potato, baked 1 med 51 Pasta 3 cups 119 Broccoli, cooked 1 cup 10 Carrot 1 med 7 Graham crackers 2 squares 11 Pizza, cheese 2 slices 41 Chocolate chip cookie 1 med 18 Total: 503 April, 1998, Montana State University-Bozeman

5 Distance running A nutrition-related problem a lot of runners have to contend with is gastrointestinal discomfort - from nausea to trots while on the trot. This seems to be a treat reserved for the distance runner - endurance cyclists don't suffer. It's thought that the problems are caused by the repeated jolting of the gut while running. Some tips that runners have found helpful are: 1 Try liquid food only for the last meal before a long run or pre-competition 2 Take care not to become dehydrated while running. Research has found that runners who take on board adequate fluid while running are less likely to suffer from gut problems 3 Avoid food high in fat or protein before your training runs, as research shows that these are more likely to induce nausea if eaten before exercise 4 Some athletes find that decreasing the fibre content of their diet before competing improves things. The endurance athlete's priority is to maximise glycogen stores by eating a highcarbohydrate diet both in training and before an event. Carbo loading is advisable, especially for an activity lasting longer than 90 minutes. Care should be taken to avoid dehydration, and this balanced against the possible benefits of taking in extra carbohydrate during the activity. Sports drinks containing maltodextrins enable delivery of some carbohydrate without compromising fluid uptake; on a cool day, however, it could be worth drinking something with a higher concentration of carbohydrate. This will slow down fluid absorption but will spare muscle glycogen. Eating during an endurance event tends to be problematic for runners, but seems to be well tolerated by cyclists.

Carbohydrates: The Energy Nutrient Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning is a trademark used herein under license.

Carbohydrates: The Energy Nutrient 2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning is a trademark used herein under license. CARBOHYDRATES Functions of Carbohydrates 1. Energy 2.