NUTRI 2000 Chapter 4 Notes
NUTRI 2000 Chapter 4 Notes Nutrition 2000
Popular in Nutrition and Health
Popular in Nutrition and Food Sciences
This 8 page Class Notes was uploaded by Amy Notetaker on Sunday February 21, 2016. The Class Notes belongs to Nutrition 2000 at Auburn University taught by Dr. Katie Vines in Winter 2016. Since its upload, it has received 129 views. For similar materials see Nutrition and Health in Nutrition and Food Sciences at Auburn University.
Reviews for NUTRI 2000 Chapter 4 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/21/16
Section 4.1: The Most Important Energy Source Carbohydrates Carbohydrates: the main fuel source for most cells in the human body (brain cells and red blood cells). Along with our cells, these are essential for our muscles too. They provide 4 kcal per gram of energy. When in need, carbs take two forms: blood glucose and glycogen. - Blood glucose: a sugar that is in our blood, also known as dextrose. - Glycogen: maintains the blood glucose amounts in the event where you haven’t eaten for some time, or if you aren’t eating enough carbs. This is stored in the liver and muscles. If you don’t eat an adequate amount of carbs, then your body starts breaking down the proteins in your body, which can lead to muscle loss. The daily intake of carbs should be about 45%-65% of carbs of the calories consumed. Photosynthesis: the plant’s way of making food. They convert sunlight into food, like glycogen. Section 4.2: Forms Of Carbohydrates Simple forms of carbohydrates are sugars. Complex forms of carbohydrates are starches and fiber (starches can be digested, fibers cannot). Monosaccharaides Monosaccharaides: these are simple sugars, which are the basic units of carbs. There are various types in foods: glucose, fructose, and galactose. Glucose: the main monosaccharaide in the body and serves as energy for the cells. - Glucose isn’t commonly found in foods, but in starches that our body digests. Some of the carbs we eat are later converted into glucose by the liver. Fructose: is fruit sugar, which is quickly metabolized by the body and then converted into glucose or other compounds. - High fructose corn syrup: processed corn syrup that contains 42%- 90% of fructose (found in candy, soft drinks, etc.). Galactose: a 6-carbon monosaccharaide that is similar and related to glucose. Disaccharides Disaccharides: formed when 2 monosaccharaides combine Sucrose: forms when glucose and fructose bond together. These are found in various foods like, sugar cane and beets. Lactose: forms when glucose binds with galactose during milk synthesis, it is essentially the sugar that is found in milk products. Maltose: when starch gets broken down to 2 glucose molecules that are bonded together. This plays a big role in the beer/liquor industry. - Fermentation: when carbon gets converted into alcohol, carbon dioxide, and acid without using oxygen. Complex Carbohydrates Polysaccharides: many single sugar units that are bound together to form a chain. These are also known as complex carbs/starch. These are found in fruits, vegetables, and grains. The term “other carbohydrates” on a food label refers to the starch content. Amylose: is a long straight chain of glucose units. This is typically found in vegetables, bread, beans, and pasta. (20% of digestible starches) Amylopectin: is a highly branched chain of glucose units and provides many ends for enzyme action. (80% of digestible starches) Cellulose: a fiber, which cannot be digested by humans. Fiber The enzymes in the GI tract cannot digest fiber. Fiber is a group of carbohydrate substances composed of cellulose, hemicellulose, pectins, gums, and mucilages, along with a noncarbohydrate substance called lignin. - On a food label, these are listed all together as dietary fiber. Whole grains: have the entire seed of the plant, along with the bran, germ, and endosperm. These are also a good source of bran fiber. Types of this include whole wheat and brown rice. Nonfermentable: (cellulose, hemicellulose, and lignin) also known as insoluble fibers, because they cannot be easily metabolized or dissolved in water. These are found in nuts, fruits, bran, skins, and some vegetables. Viscous: (pectins, gums, mucilages) also known as soluble fiber, are readily fermented by the bacteria, which are in the GI tract. These are found in beans and oats. - Soluble fiber: slows the rate of absorption, reduces blood cholesterol, and controls blood glucose. Functional fiber: these are non-digestible carbohydrates, which is the fiber that is added to foods to provide extra health benefits. Prebiotics: a group of functional fibers that has short chain of carbohydrates/oligosaccharides which are not digested, but fermented in the colon instead. Section 4.3: Carbohydrates In Foods Grains, vegetables, fruits, and dairy contain the healthiest carbohydrates in our diet. Most of the carbohydrates we eat come from starches. The best sources of starch are beans, potatoes, cereal, and pasta. The top carbohydrate sources for U.S. adults have been soft drinks, white bread, cookies, cakes, sugars, syrups, potatoes, and jams. Foods that have the most calories from carbohydrates are honey, jam, jelly, and table sugar. Foods with a good/moderate amount of carbohydrates are dry beans, oatmeal, broccoli, legumes, etc. Foods with no carbohydrates are beef, eggs, chicken, fish, butter, margarine, and vegetable oil. Whole Grains The 2010 dietary guidelines say that half of the grains we eat should be whole grain, and that we should have 2-3 daily servings of whole grains. - Consuming whole grains reduces the risk of cardiovascular disease, diabetes, obesity, etc. The average American intake of grains is 6.4 ounces, and only 0.6 ounces of whole grains. To confirm that a food item is made entirely of whole grains, look at the ingredient list and make sure that the first word is “whole”. To simplify the search for which products are whole grain and which are not, the “whole grain stamp” is used. There are two types of the stamp: - The 100% stamp: used on a product if all the grain ingredients used are whole grains, and if there are at least 16 grams of whole grains in one serving. - The basic stamp: used on a product if it contains some refined grain and at least 8 grams of whole grains in one serving. Vegetables Vegetables are a good source of carbohydrates in the form of starch and fiber. These are low in fat and in calories with many nutritional and health benefits. Eating a good amount of vegetables reduces the risk of heart disease, diabetes, and diabetes. There are 5 groups of vegetables: dark green, starchy, red and orange, beans, and peas. The amount of vegetables you need is determined on gender, age, and level of physical activity. Fruits Fruits provide carbs in the forms of natural sugars and fiber. People who eat more fruits have a reduced risk of chronic diseases. Fiber found in fruits helps in weight maintenance, lowering blood cholesterol, and heart disease. Diary Dairy products provide carbs in the form of lactose. All dairy products have a different amount of lactose in them. Foods containing high levels of lactose: fluid milk, plain yogurt, half and half, sour cream, heavy cream, cottage cheese, ricotta cheese, ice cream, and ice milk. Foods containing low levels of lactose: lactase enzyme treated milk, sherbet, aged cheese, and processed cheese. Nutritive Sweeteners Nutritive Sweeteners: provide calories for the body. Alternative Sweeteners: provide no calories for the body. Sucrose comes from sugar canes and sugar beet plants. Sugars and sugar alcohols provide calories and sweetness. Since monosaccharaides and disaccharides provide calories, they are categorized as nutritive sweeteners. Added sugars: caloric sweeteners that are added to foods while they are being processed/prepared for consumption. An average Americans consumes about 20 teaspoons of added sugars a day, when the recommended intake is 8 teaspoons. 14.6% of our calories come from added sugars, and 60% of the 14.6% is from beverages, grain based desserts, and fruit drinks. High fructose corn syrup (HFCS): a sweetener that has been processed so that the glucose in corn syrup is converted into fructose. This is found in many types of foods, mostly in soft drinks. An average American consumes about 60 pounds of HCFS a year, which also leads to obesity. Sugar alcohols: provide sweetness without all the sugar and calories, but stay in the digestive tract for a longer amount of time due to slow digestion. Excess intake can have laxative effects. Sorbitol: a sugar alcohol that yields 3 kcal per gram and is found in sugarless gums and dietetic foods. Xylitol: a sugar alcohol, which is derived from xylose. Alternative Sweeteners Alternative sweeteners: yield little to no calories when eaten. Saccharin: the oldest alternative sweetener. Aspartame: contains phenylalanine, aspartic acid, and methanol. This yields 4 kcal per gram and is 200 times sweeter than sucrose. Phenylketonuria (PKU): a disease, which prohibits phenylalanine to be properly metabolized. People who have this condition should avoid aspartame. Sucralose: made by adding 3 chlorines to sucrose and cannot be broken down or absorbed. This yields no kcal per gram and is used in gum, baked goods, gelatin, etc. This is 600 times sweeter than sucrose. Neotame: similar to aspartame, but PKU friendly. This is 7,000 to 13,000 times sweeter than table sugar. Acesulfame-K: is an organic acid and is 200 times sweeter than sucrose. Stevia: is derived from the South American shrub. This yields no kcal per gram and is 100 to 300 times sweeter than sucrose. Luo han guo: is the extract from the monk fruit. This is 150 to 300 times sweeter than sucrose. Advantame: is similar to aspartame but much sweeter and PKU friendly. This is 20,000 times sweeter than sucrose. Section 4.4: Making Carbohydrates Available for Body Use Starch and Sugar Digestion Amylase: an enzyme, which breaks down starch. In the mouth, salivary amylase breaks down starch into maltose. In the stomach, a strong acid inactivates the salivary amylase. In the pancreas, pancreatic enzymes break down starch into maltase inside of the small intestine. - The enzyme maltase acts on maltose and produces 2 glucose molecules. - The enzyme sucrase acts on sucrose and produces glucose and fructose. - The enzyme lactase acts on lactose and produces glucose and galactose. In the small intestine, enzymes in the walls breakdown disaccharides sucrose, maltose, and lactose into monosaccharaides glucose, galactose, and fructose. In the large intestine, bacteria ferment fiber into acids and gases. In the rectum and anus, fiber, which cannot be fermented, is released through the feces. Lactose Maldigestion and Lactose Intolerance Primary lactose maldigestion: usually develops during ages 3 to 5, about 75% of the population has this condition but not everyone shows it. Secondary lactose maldigestion: a temporary condition, which happens when another condition develops and cause lactase production to decrease. Congenital lactase deficiency: when lactase production has not been available since birth. Lactose intolerance: when you consume lactose and have symptoms consisting of gas, bloating, cramps, and diarrhea. When lactose products are combined with non-lactose products, a person who is lactose intolerant more easily digests it. Carbohydrate Absorption Glucose and galactose follow an active absorption process. Fructose follows a facilitated absorption process. Single sugars in the absorptive cells are transferred through the portal vein, which lead to the liver. The liver metabolizes them and converts galactose and fructose into glucose. The liver will transport this glucose into the bloodstream for the organs; produce glycogen for storage of carbohydrate, and produces fat. Fiber and Intestinal Health The bacteria in the large intestine ferment soluble fibers into acids and gases. When the acids are absorbed they provide calories for the body. Soluble fibers provide 1.5 to 2.5 kcal per gram. Insoluble fiber cannot be digested so it is excreted as feces. When you don’t eat an adequate amount of fiber, you may become constipated, and other medical conditions can occur. - Diverticula: pouches that develop through the exterior wall of the large intestine. - Hemorrhoid: when the veins in the anus swell due to too much applied pressure. - Diverticulosis: a condition, which results in too many diverticula in the large intestine. - Diverticulitis: inflammation of the diverticula. Studies show that an increased intake of fiber reduces the risk of colon cancer. Section 4.5: Putting Carbohydrates to Work in the Body Providing Energy Glucose supplies calories for the body to use. The brain and CNS, get energy from only glucose, unless the diet doesn’t have any. If the body doesn’t have glucose, then the brain and CNS use ketone bodies to get the energy they need. Ketone bodies: contain 3 or 4 carbons and are the atrial breakdown products of fat. If you don’t have enough carbs in your diet, then the body uses proteins to make glucose. Long term of this can affect all muscles in the body, which include the heart, liver, etc. Ketosis: having too many ketone bodies in the bloodstream and tissues. Regulating Blood Glucose One of the many roles of the liver includes being a guard against extra glucose entering the blood stream after eating a meal. The liver and pancreas both regulate glucose. Insulin: a hormone released by the pancreas when blood glucose is high. Glucagon: a hormone released by the pancreas when a person hasn’t eaten for a while (has the opposite effect of insulin). Epinephrine helps insulin and glucagon quickly transport to the bloodstream. Hyperglycemia: high blood glucose levels. Hypoglycemia: low blood glucose levels. The body reacts uniquely to different types of carbohydrates. The glycemic index: a way to avoid hyperglycemia by measuring how carbohydrates raise the blood glucose. Starch structure, fiber content, food processing, physical structure, and fat content can determine the glycemic index. If you combine low glycemic index foods and high glycemic index foods then it will keep your blood glucose level, and not spike up. Fiber: Reducing Cholesterol Absorption and Obesity Risk Good sources of viscous fiber include: apples, oranges, kidney beans, bananas, carrots, barley, oats, etc. Eating a high amount of viscous fibers reduces cholesterol levels, the risk of heart disease, and obesity. Section 4.5: Carbohydrate Needs RDA for carbohydrates in adults is about 130 grams. The 2010 dietary guidelines state that we should eat more fiber rich fruits, vegetables and whole grains. How Much Fiber Do We Need? Fiber intake should be at least 25 grams a day for women and 38 grams a day for men. The average fiber intake in North America for women is about 13 grams a day and 17 grams a day for men. Eating too much fiber is also not good, so if you do increase your fiber intake, make sure to increase you water intake as well. How Much Sugar is too Much? Sugar provides empty calories and increase tooth decay risk. A moderate intake of added sugars is about 10% a day of the caloric intake, which is about 50 grams of sugar. North Americans eat an average of 82 grams of added sugar a day. Foods that are “low fat” or “fat free” usually contain a lot of added sugar to make up for the taste. High sugar intake in children can cause hyperactivity. Excess sugar can lead to cavities in your teeth and tooth decay. Nutrition and Your Health Diabetes: happens when blood glucose regulation fails. There are 2 types: - Type 1 diabetes: begins in late child hood and is due to total insulin deficiency due to the insulin production cells being damaged. Insulin therapy is needed for this condition. - Type 2 diabetes: usually happens after age 30 is the more common type. This condition is usually a result of obesity, which causes insulin resistance. Hypoglycemia: people who take insulin due to diabetes, can develop hypoglycemia I they don’t eat enough. Metabolic syndrome: when a person has poor blood glucose regulation, hypertension, increased blood triglycerides, and other health issues. This condition is also known as syndrome X.
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'