Pennington Biomedical Research Center Awesome.2Cents! A Healthy Lifestyle Curriculum for Teens…Lesson # 5 Fueling your body (Carbohydrates)Content outline 1. Carbohydrates are essential sources of energy. 2. Carbohydrates come in many forms and can influence digestion, absorption and metabolism. 3. Carbohydrates come mainly from plant sources.Louisiana content standards: 1-H-1, 1-H-2, 1-H-3, 1-H-4, 1-H-5, 1-H-6, 2-H-1, 2-H-2, 3-H-1, 3-H-2, 5-H-6 1-M-2, 1-M-3, 2-M-2, 3-M-1, 4-M-5, 5-M-4, 5-M-5, 6-M-1Objectives/Expected Learner Outcomes Students learn the chemistry of carbohydrates. Students learn how carbohydrates are metabolized. ` Students learn that carbohydrates make up a significant part of their diet. Students learn the difference between refined and whole grain.Lesson and Strategies Student group targeted 8-12th gradeTime required Teacher Preparation: 15-20 minutes Assessment: 10 minutesMaterials and Resources Carbohydrate sources: table sugar, rice, pasta, Fiber One cereal, Handouts Power point presentation Projector Screen Laptop/Computer Various food packages high in carbohydrates, such as breads, cereal, pasta, etc. with Nutrition Facts Panel. The Nutrition Facts Panel handout (if needed)Motivation and ExplanationsIn this lesson, kids divided based on their consumption of certain kind of fast food learnto make healthier choice in their category.Teacher PreparationBefore class, make copies of the handouts and homework assignment.
Lesson PlanSlide Lesson1 Title slide: Fueling your body2 Say: This lesson will cover: What are carbohydrates? Functions of carbohydrates Digestion and metabolism Types of carbohydrates. Dietary fiber. Chronic diseases and carbohydrate intake. How much should you have?3 Images Say: No doubt you have seen these statements and images on TV, video, when surfing the web, in the newspaper. Is this really true? Is it healthy not to have any carbohydrates? We will explore that in this lesson. Do: Show statements and images on the slide.4 What are carbohydrates? Say: Carbohydrates are simple or complex structures made up of carbon, hydrogen and oxygen. Simple carbohydrates are small molecules, mainly 5 or 6 carbon molecules. Complex structures may be hundreds or thousands of glucose molecules, together with components such as lipids, nitrogen, or protein. Heparin and mucopolysaccharides are examples of complex carbohydrates. What you might have heard about carbohydrates and starches is that they are bad for you. But lets take a look at carbohydrates and see how they might be important. They are needed for energy.5 What are carbohydrates? Say: Carbohydrates are simple or complex structures made up of carbon, hydrogen and oxygen. Glucose is the simplest carbohydrate unit. It is a monosaccharide. A simple carbohydrate is in fact glucose or blood sugar (or dextrose). It flows through the blood stream and goes to every cell of the body, where it is converted to energy. Glucose, fructose (from fruits) and galactose are monosaccharides. They are absorbed in the intestines in to the bloodstream.
6 What are carbohydrates? Say: Disaccharide is a molecule made up of two sugar units. Other examples of disaccharides are lactose or milk sugar and maltose. Lactose is made up of glucose and galactose. Some people lack the enzyme that digests the bond between glucose and galactose in a condition called lactose intolerance. Table sugar, or sucrose, is another example of a disaccaride. It is made up of two simple glucose units.7 What are carbohydrates? Say: Complex carbohydrates are made up of many hundreds and thousands of glucose units. Some complex carbohydrates are digestible such as starch. They are slower absorbing sugars because it takes a lot longer for the digestive system to break them down. Only after breaking them down into glucose is the bloodstream able to absorb the glucose. Other complex carbohydrates are indigestible such as cellulose. Indigestible carbohydrates are called dietary fiber. The bond between the glucose units determines if it is digestible or not. There are also complex carbohydrates, starches, made up of chains of glucose molecules.
8 Functions of carbohydrates Say: Carbohydrates main role is to provide fuel. If we have adequate carbohydrate, we prevent the breakdown of protein for energy. Carbohydrate in the diet actually helps the breakdown of fat. With adequate carbohydrate in the diet, fat is completely broken down and used for energy. Plant sources of carbohydrates are the best sources of fiber in the diet. Some of the best plant sources of fiber are whole grain breads and cereals, beans and peas, lentils, popcorn.9 Carbohydrates as fuel Say: All starches, saccharides and mixed carbohydrates are converted to the simplest form of carbohydrate, glucose, during digestion and are absorbed in the bloodstream as glucose units. Glucose is the most common type of energy currency used by the cells, in addition to fatty acids, and at times, ketones.10 Carbohydrates as fuel Say: The brain uses mainly glucose for energy. Our brains alone use about 120 grams of carbohydrate for energy. Therefore it is important that we eat enough carbohydrates every day. It is because of carbohydrates that we have the energy and mental capacity to do homework, read, and stay awake. The heart muscle can use ketones for energy if it must, but it prefers glucose. The brain can also use ketones, but ketones are not the preferred fuel and can cause feeling of lethargy and headache. The muscle cells use mainly fat for energy at rest, and glucose under high aerobic conditions such as running. During sudden burst of energy when doing aerobic activity, muscle uses phosphagens and once they are depleted, then glucose for energy.11 Sparing protein Say: When we have adequate carbohydrate intake, we spare protein use for energy.
About 15 percent of energy comes from protein when we are on a typical diet. Carbohydrates are an efficient energy source, as are fats, because there is no waste. All of the molecule can be used for energy.12 Sparing protein Say: If we do not have adequate carbohydrate intake: We have to break down body protein to burn it for energy. That means that we lose muscle mass on low carbohydrate diets. Body protein is used for energy and we don’t have adequate protein for maintaining cell structures. This can lead to kidney stones over time due to kidneys having to get rid of high nitrogen levels in the body13 Helping fat breakdown Say: When a diet is low in carbohydrates, fats are not broken down completely. We produce ketone bodies. Ketone bodies are produced in the body when fat is not completely broken down. Ketone bodies are harmful compounds. Ketone bodies can accumulate in the bloodstream and cause blood to become more acidic than normal. They can build in the bloodstream and cause the blood to become more acidic than is healthy and can eventually at high enough level cause a person to go into coma. Severe ketosis can cause coma and death. Ketosis can also happen in diabetes with excess insulin.14 Helping fat breakdown For complete fat breakdown and to prevent ketone bodies from building in the bloodstream, we should consume about 50 to 65 percent of calories (majority of energy) from carbohydrates. In that way, we have enough energy for our brain, muscles and internal organs to use for energy.15 Providing dietary fiber Say: Plants are a good source of dietary fiber. Dietary fiber helps with digestion. It helps keep harmful materials from being in contact with intestinal walls. It helps speed elimination. It binds harmful molecules in the intestines. Dietary fiber can help prevent chronic diseases and can help in weight control. Studies show that those that eat a high fiber diet have lower cholesterol levels, less diabetes, they have lower body weights, and smaller waist circumferences.
16 Digestion of Food Breakdown of carbohydrates Say: We consume foods that are (Usually) a mix of protein, fat and carbohydrate. Digestion is breaking foods down to its basic components, amino acids, fatty acids, and glucose molecules. After breaking food down, we absorb the smaller molecules. Foods that we consume (like bread, meat, and vegetables), are not in a form that the body can immediately use as nourishment. These foods and drinks that we consume must be changed into smaller molecules of nutrients before they can be absorbed in the blood and carried to cells of the body. Digestion is the process that breaks foods and drinks down into their smallest parts so that the body can used them to build and nourish cells and to provide energy.17 Digestion of carbohydrates Say: Carbohydrate digestion starts in the mouth and continues in the small intestine into glucose and other 6 carbon sugars. 1) Starch is first broken down (in the mouth) by an enzyme in saliva and later by pancreatic juices to form maltose. 2) Maltose (2 bound glucose molecules) is split into glucose molecules by an enzyme called maltase in the small intestine. 3) Milk sugar is broken down into glucose and galactose by an enzyme (lactase) in the small intestine. 4) Table sugar is broken down into glucose and fructose by an enzyme found in the small intestine. These are then absorbed in the bloodstream. More processed foods are digested and absorbed faster than foods that are less processed.18 Where are Carbohydrates Found? Say:
All the staples in our diet are really carbohydrates. We find carbohydrates in: Rice Pasta Potatoes Breads and rolls Crackers and snacks Vegetables and fruits also have carbohydrates but in varying and lesser amounts.19 Where are Carbohydrates Found? Say: Carbohydrates (simple and complex) can be found in the: Milk and dairy group. Milk and dairy have lactose. Some individuals develop lactose intolerance as they grow older. Lactose intolerance means that the milk sugar is indigestible. The person stops producing an enzyme necessary for that. This condition is not serious, and can be easily overcome by consuming milk where lactose is already split into galactose and glucose, or by taking an enzyme supplement. Vegetable group. Most vegetables have long chain carbohydrate molecules such as cellulose, starch, and dextrans. Fruit group. The fruit group contains sucrose, glucose, cellulose, starch, and dextrans. Grains group. The grain group is one of the best sources of dietary fiber, cellulose. Grains also are the best sources of digestible carbohydrate, starch.20 Types of carbohydrates: simple Say: Sugar is found naturally in many foods. It is also called simple carbohydrate. Food sources of natural sugar include fruit, vegetables, milk and yogurt. Foods containing natural sugars are nutritious, providing many vitamins, minerals, phytochemicals (natural plant chemicals) and antioxidants. They are also good sources of fiber, as in fruits, vegetables and whole grains. Examples of refined sugars are: sucrose, glucose, dextrose, maltose and high fructose corn syrup.21 Simple carbohydrates Say: Along with complex carbohydrates, fruits and vegetables also contain some simple sugars. Milk contains simple sugars, too. Sucrose, glucose, dextrose, maltose and high fructose corn syrup are some examples of simple carbohydrates. Simple carbohydrates are naturally in many foods, and they are also added to foods during processing such as cakes, candy, cookies and ice cream. The difference between these food sources of simple sugars (milk, fruits, and vegetables) and other food sources of simple sugars is that they are packed with nutrients, whereas cake and other refined sugar products only contain energy and very little vitamins and minerals.
22 Types of carbohydrates: complex Say: Starch, also known as complex carbohydrate or polysaccharide, is present in foods such as cereals, whole grains, rice, pasta, potatoes, peas, corn and legumes. Fiber, also a complex carbohydrate, is found in foods of plant origin. Fiber can soluble or insoluble. Some fiber is indigestible and can speed up the passage of food through the intestinal track.23 Complex carbohydrates Say: Examples of complex carbohydrates are amylose, amylopectin, starch and cellulose. Complex carbohydrates are found in fruits, vegetables, and grains (like bread, rice, and pasta). Food sources of complex carbohydrates are important contributors of vitamins, minerals, fiber, and a host of phytonutrients. When choosing grain food choices, it is important to choose whole grains often. Does anyone know why? Whole grain products retain the nutrients, fiber and phytochemicals in the foods.24 Refined vs whole grains Say: This graph shows the percent of nutrients remaining after whole wheat flour is refined into white flour. As you can see, less than 50 percent of the nutrients are retained after processing. Most grain products are enriched; that means that nutrients are added back in the grain product. Food enrichment is the process whereby nutrients (vitamins and minerals) are added to food. This normally happens during or directly after manufacturing. Grain products are enriched with thiamin, riboflavin, niacin, and iron. Refined Grains are less nutrient-dense and more energy-dense than Whole Grains.
25 Types of carbohydrates: Complex Some carbohydrates are indigestible. The stalk from many plants, outer skin of fruits and vegetables, and outer layer of wheat are indigestible. It is referred to as Dietary Fiber. Fiber, also a complex carbohydrate, is found in foods of plant origin.26 Types of dietary fiber Say: Dietary fiber includes all parts of plant foods that your body can’t digest or absorb. Fiber is often classified into two categories: Those that don’t dissolve in water are called insoluble fiber. Those that do dissolve in water are called soluble fiber. Good sources of insoluble fiber are whole-wheat flour, wheat bran, nuts and many vegetables. Good sources of soluble fiber are oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium. Soluble fiber helps to reduce cholesterol levels.
27 The role of dietary fiber Say: The amount of each type of fiber varies in different plant foods, so to receive the greatest health benefit, it is important to eat a wide variety of high-fiber foods. Benefits of eating a diet high in fiber include: 1) Prevention or relief of constipation because indigestible fiber attracts water and helps move waste out of the body faster 2) A lower risk for disorders such as hemorrhoids, irritable bowel syndrome, and diverticular disease 3) Lower blood cholesterol levels by trapping and removing cholesterol from the intestinal track 4) Slower the absorption of sugar in the intestinal track which can improve blood sugar levels 5) Lower the risk for the development of type 2 diabetes 6) Aid in weight loss as high-fiber foods tend to make a meal feel larger and linger longer so that you stay full longer .28 What to have? Simple or Complex? Say: The new Dietary Guidelines for Americans (DGA) stress the importance of consuming more complex carbohydrates over simple carbohydrates. Many studies show that complex carbohydrates are beneficial in reducing the incidence or severity of chronic diseases. The new DGA (2010) says that “half our grains should be whole grains.” Many people do not consume whole grain products because of the texture or taste, however, the recommendation is to consume more whole grains. Complex carbohydrates are found in foods stressed by the 2010 DGA like: Whole grains Fruits Vegetables Lentils, beans, and peas Do: Provide students with Nutrition Facts Panel or boxes of foods to examine the label. Show from the label the carbohydrate content of foods. Ask the students to find the amount of fiber, simple sugars, and total carbohydrate. Discuss the list of ingredients and highlight those that list whole wheat as the first ingredient.29 Simple or Complex? Say: Food sources of simple carbohydrates (like refined grains and desserts) are often referred to as “energy-dense” foods; whereas, food sources of complex carbohydrates (like fruit, whole grains and vegetables) are referred to as “nutrient-dense” foods.
Whereas energy-dense foods primarily provide calories (energy) from added sugars and fats and little nutrients, nutrient-dense foods are generally low in calories (and fat) and are packed with nutrients.30 Too high an intake of refined grains has been shown to … Say: Increase the risk of developing coronary heart disease, increase the risk of developing type 2 diabetes and other chronic diseases.31 The 2010 DGA indicate that Say: Before you eat, think about what goes on your plate or in your cup or bowl. Foods like vegetables, fruits, whole grains, low-fat dairy products, and lean protein foods contain the nutrients you need without too many calories. Improving what you eat and being active will help to reduce your risk of chronic diseases such as diabetes, heart disease, some cancers, and obesity. Americans should reduce foods that are high in sodium, solid fats (major sources of saturated fats and trans fats), cholesterol, added sugars, refined grains, and for some Americans, alcohol. Replacing these foods and beverages that provide substantial amounts of nutrients, nutritious foods that are recommended for nutrient adequacy, disease prevention, and overall good health. These include vegetables; fruits; whole grains; fat-free or low-fat milk and milk products; protein foods, including seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds; and oils would improve the health of Americans.32 DGA tells us to eat at least half the grains as whole grains. Does anyone know why? Say: 1020 DG Policy document: Whole grains are a source of nutrients such as iron, magnesium, selenium, B vitamins, and dietary fiber. Whole grains vary in their dietary fiber content. Moderate evidence indicates that whole-grain intake may reduce the risk of cardiovascular disease and is associated with a lower body weight. Limited evidence also shows that consuming whole grains is associated with a reduced incidence of type 2 diabetes. Consuming enough whole grains helps meet nutrient needs. Choosing whole grains that are higher in dietary fiber has additional health benefits. At least half of recommended total grain intake should be whole grains. Less than 5 percent of Americans consume the minimum recommended amount of whole grains, which for many is about 3 ounce-equivalents62 per day. On average, Americans eat less than 1 ounce-equivalent of whole grains per day. Americans should aim to replace many refined-grain foods with whole-grain foods that are in their nutrient-dense forms to keep total calorie intake within limits. When refined grains are eaten, they should be enriched. Individuals may choose to consume more than half of their grains as whole grains. To ensure
nutrient adequacy, individuals who consume all of their grains as whole grains should include some that have been fortified with folic acid, such as some ready- to-eat whole-grain cereals. This is particularly important for women who are capable of becoming pregnant. The recommendation to consume at least half of total grains as whole grains can be met in a number of ways. The most direct way to meet the whole grain recommendation is to eat at least half of one’s grain-based foods as 100% whole-grain foods. If the only grains in the ingredients list are whole grains, the food is a 100% whole-grain food. The relative amount of grain in the food can be inferred by the placement of the grain in the ingredients list. The whole grain should be the first ingredient or the second ingredient, after water. For foods with multiple whole-grain ingredients, they should appear near the beginning of the ingredients list.33 Whole grains sources Say: Whole grain foods are most grain products that are not processed. They include: Brown rice, Buckwheat, Bulgur (cracked wheat), Oatmeal, Popcorn, Whole wheat cereal, Muesli, Whole grain barley, Whole grain cornmeal, Whole rye, Whole wheat bread, Whole wheat crackers, Whole wheat pasta, Whole wheat sandwich buns, Whole wheat rolls, Whole wheat tortillas, and Wild rice.34 Refined Grains Say: Sources of refined grains are: Cornbread , Corn tortillas, Couscous, Crackers, Flour tortillas, Grits, Noodles, Spaghetti, Macaroni, Pitas, Pretzels, Corn flakes, White bread, White sandwich buns, White rolls, and White rice.35 How much do I need? Say: The recommended intake for carbohydrates is 130 grams/day for children, adolescents, and adult males and females. How do I know how much foods have? Look at the Nutrition Facts Panel of the foods that you are consuming and calculate if total daily food intake will give you about 50-65% of energy from carbohydrates. Can you calculate that?36 How much do I need? Say: A typical diet contains from 50 to 65 percent of energy from carbohydrates. We can find out how many grams of carbohydrate that is on a 2200 Calorie diet: 2200 Cal x 50% = 1100 Cal 100 %
1100 Cal = 275 grams of carbohydrate 4 Cal/g If your energy intake level is 2200 calories a day, you should consume about 275 grams of carbohydrates.37 Summary38 References: Dorothy West, Janis, P. Meek. Nutrition Food and Fitness. The Goodheart-Willcox Company, Inc. 2006. Peck Ritter, Biochemistry. Brooks/Cole Publishing Company, 1996. Len Marquart,Joanne L. Slavin, R. Gary Fulcher. Whole grain foods in health and disease. American Association of Cereal Chemists, 2nd printing, 2005. David Kritchevsky, Charles Bonfield (Ed). Dietary Fiber in Health and Disease. Eagan Press, 1995.39 Authors: Heli J. Roy, PhD, RD Shanna Lundy, MS Division of Education Phillip Brantley, PhD, Director Pennington Biomedical Research Center Steven Heymsfield, MD, Executive Director The Pennington Biomedical Research Center is a world-renowned nutrition research center. Mission: To promote healthier lives through research and education in nutrition and preventive medicine. The Pennington Center has several research areas, including: Clinical Obesity Research Experimental Obesity Functional Foods Health and Performance Enhancement Nutrition and Chronic Diseases Nutrition and the Brain Dementia, Alzheimer’s and healthy aging Diet, exercise, weight loss and weight loss maintenance
The research fostered in these areas can have a profound impact on healthyliving and on the prevention of common chronic diseases, such as heart disease,cancer, diabetes, hypertension and osteoporosis.The Division of Education provides education and information to the scientificcommunity and the public about research findings, training programs andresearch areas, and coordinates educational events for the public on varioushealth issues.We invite people of all ages and backgrounds to participate in the excitingresearch studies being conducted at the Pennington Center in Baton Rouge,Louisiana. If you would like to take part, visit the clinical trials web page atwww.pbrc.edu or call (225) 763-3000.Edited: October 2012