NUTRITION. What determines a diet? What does our body need? Sources of Carbohydrates. Carbohydrates 10/01/2012

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1 Movie: Nutrition and Digestive Health Eating for your future! NUTRITION Questions to Answer: What eating habits can affect the way our digestive system works? Give THREE examples and explain each example How do enzymes work to aid in digestion? Give TWO examples and explain what happens. What is a balanced meal? What is the Live Food diet? Evaluate your eating habits. During the movie, look for events that you can relate to, or events that really surprised you. You are what you eat! What determines a diet? What does our body need? The amount and type of food that we each eat from day to day defines our diet The body requires certain elements, in various combinations, to provide energy for the growth and repair of tissues and the general maintenance of the body systems. The food substances that provide these are the of six different types: Carbohydrates Fats Proteins Vitamins Water Minerals Carbohydrates Sources of Carbohydrates The body s main source of energy Formed from carbon and hydrates (water) Simple carbohydrates = monosaccharides = single sugars Glucose is one of the most important monosaccharides Disachharides are double sugars Table sugar (sucrose) = glucose + fructose Foods made from grains, along with starchy vegetables and fruits, are rich sources of carbohydrates Condemned as being the major contributor of body fat in overweight people Essential part of our diet. When the body does not get enough carbohydrates, fats and structural proteins will be broken down to fuel the body s energy needs. Junk foods are rich in sugar but have little to no nutritional value besides quick energy 1

2 Question? What is the main function of carbohydrates in the body? What are 5 good sources of carbohydrates? Fats for Storage Fats are transformed carbohydrates When the body turns carbohydrates into fats for storage, these fats are stored in the adipose tissues of the body These fats exist in a liquid state (oil) inside the adipose cells Fats for Storage Fats, like carbohydrates, are used to provide energy for body activities. Fats contain twice the amount of energy per gram as either carbohydrates or proteins Fats for Storage Fats take longer to digest, staying in the stomach for about 3.5 hours. This gives us a feeling of fullness and satisfaction after eating. Fats are necessary for dissolving fat-soluble vitamins, such as Vitamin A, D, E, and K. Sources of Fat Saturated fats These fats are derived from animal products such as meat, dairy and eggs. But they are also found in some plant-based sources such as coconut, palm and palm kernel oils. These fats are solid at room temperature. Saturated fats directly raise total and LDL (bad) cholesterol levels. Conventional advice says to avoid them as much as possible. More recently, some have questioned this, as there are different kinds of saturated fats, some of which have at least a neutral effect on cholesterol. Sources of Fat Trans Fats or Hydrogenated Fats Trans Fats are actually unsaturated fats, but they can raise total LDL (bad) cholesterol levels while also lowering HDL (good) cholesterol levels. Trans fats are used to extend the shelf life of processed foods, typically cookies, cakes, fries and donuts. Any item that contains hydrogenated oil or partially hydrogenated oil likely contains trans fats. Hydrogenation is the chemical process that changes liquid oils into solid fats. Since January 2006, all food manufacturers are required to list trans fat content on food labels. 2

3 Sources of Fat Unsaturated fats Monounsaturated fats and polyunsaturated fats are two types of unsaturated fatty acids. They are derived from vegetables and plants. Monounsaturated fats are liquid at room temperature but begin to solidify at cold temperatures. This type of fat is preferable to other types of fat and can be found in olives, olive oil, nuts, peanut oil, canola oil and avocados. Some studies have shown that these kinds of fats can actually lower LDL (bad) cholesterol and maintain HDL (good) cholesterol. Polyunsaturated fats are also liquid at room temperature. These are found in sesame, corn, cottonseed and soybean oils. This type of fat has also been shown to reduce levels of LDL cholesterol, but too much can also lower your HDL cholesterol. What is Cholesterol? Cholesterol is a white, waxy substance which has several useful functions in the body. Under normal conditions, including a proper diet, the liver produces all the cholesterol needed by the body. The cholesterol is then transported to the body via the bloodstream What is Cholesterol? High Density Lipoproteins High density lipoprotein, also known as HDL, is considered the "good" cholesterol. HDL is produced by the liver to carry cholesterol and other lipids (fats) from tissues and organs back to the liver for recycling or degradation. High levels of HDL are a good indicator of a healthy heart, because less cholesterol is available in your blood to attach to blood vessels and cause plaque formation. What is Cholesterol? Low Density Lipoproteins Low density lipoproteins, also referred to as LDL, is known as the "bad cholesterol". LDLs are produced by the liver and carry cholesterol and other lipids (fats) from the liver to different areas of the body, like muscles, tissues, organs, and the heart. It is very important to keep LDL levels low, because high levels of LDL indicate that there is much more cholesterol in the blood stream than necessary, therefore increasing your risk of heart disease. What is Cholesterol? Cholesterol has been linked to the occurrence of coronary heart disease. Under certain conditions, cholesterol clings to the walls of large blood vessels, thus reducing their diameter and restricting the flow of blood. The gradual reduction in the diameter of these blood vessels is a leading cause of heart attacks. 3

4 Question? What are the three types of fats? Which fat is derived from olive oil? Proteins Proteins are essential for the building, repair, and maintenance of body tissues. Proteins form a major part of the muscles, the internal organs, the brain, nerves, skin, hair, and nails Proteins Proteins are giant molecules made up of hundreds of units called amino acids Amino acids are composed of nitrogen, hydrogen, and oxygen atoms There are only 22 different kinds of amino acids in the human body. The order and number of these amino acids determine the type of protein Proteins When proteins enter the body, they pass into the digestive tract. There, enzymes disassemble the long complex chains into separate amino acid units, making them small enough to pass through the pores of cell membranes. After travelling through the blood, they are then reassembled into new chains inside various body cells. Proteins The human body can make some of the amino acids it requires, but is unable to make others. These must be supplied in the diet. Amino acids that the body cannot make for itself are called Essential Amino Acids The quality of a protein, in terms of its food value to the human body, is determined both by the number of essential amino acids it contains and by the current needs of the body for particular types or amounts of amino acids. Sources of Protein Animal Proteins rich in essential amino acids Meat Fish Eggs Other animal products Plant/Vegetable Proteins usually incomplete; they either entirely lack or contain very small amounts of essential amino acids Flour Rice Cereals Peas Beans Nuts 4

5 Body Protein Requirements Required for the repair and maintenance of body tissues Required during rapid periods of growth production of new cells and repair of old cells. The faster you grow, the more protein you need. Required during pregnancy and after birth Question? What are four good sources of protein? Where in the digestive system does protein chemically and mechanically break down? What enzyme is responsible for the breakdown of protein in the stomach? Vitamins There are few vitamins which the body can produce on its own. Vitamin D produced when the skin is exposed to sunlight. We get Vitamin D from milk, since cows produce it while feeding in sunny pastures. Some of the types of beneficial bacteria living in the large intestine produce Vitamin K and some B Vitamins. These are then absorbed through the lining of the colon. Remaining Vitamins must be obtained through the foods that we eat, primarily fruits and vegetables Sources of Vitamins in the Diet A well-balanced diet should provide all the required vitamins without the need to resort to vitamin supplement pills. However, there are several reasons why even a balanced diet may be short of some vitamins Garden soils that lack essential elements grow vegetables that lack some vitamins Fruits and Veggies that are transported long distances, or that are harvested before they are ripe, can also be low in vitamin content Freezing and storing foods depletes vitamins, as do cooking and canning processes Sources of Vitamins in the Diet Vegetables should be cooked lightly and served quickly. In some vegetables and fruits, the best vitamin supply lies in the skin. This supply is thrown away if these vegetables and fruits are peeled. Vitamins and Minerals Vitamins fall into two categories: fat soluble and water soluble. The fat-soluble vitamins A, D, E, and K dissolve in fat and can be stored in your body. The water-soluble vitamins C and the B complex vitamins (such as vitamins B6, B12, niacin, riboflavin, and folate) need to dissolve in water before your body can absorb them. Because of this, your body can't store these vitamins. Any vitamin C or B that your body doesn't use as it passes through your system is lost (mostly when you pee). So you need a fresh supply of these vitamins every day. 5

6 Vitamins and Minerals Vitamins and Minerals Whereas vitamins are organic substances (made by plants or animals), minerals are inorganic elements that come from the soil and water and are absorbed by plants or eaten by animals. Your body needs larger amounts of some minerals, such as calcium, to grow and stay healthy. Other minerals like chromium, copper, iodine, iron, selenium, and zinc are called trace minerals because you only need very small amounts of them each day. Vitamins and minerals boost the immune system, support normal growth and development, and help cells and organs function properly. For example, you've probably heard that carrots are good for your eyes. Carrots are full of substances called carotenoids that your body converts into vitamin A, which helps prevent eye problems. To have strong bones, you need to eat foods such as milk, yogurt, and green leafy vegetables, which are rich in the mineral calcium. Another vitamin, vitamin K, helps blood to clot (so cuts and scrapes stop bleeding quickly). You'll find vitamin K in green leafy vegetables, broccoli, and soybeans. Supplements Question? m/nutrition/vitamins- Minerals.htm What is a good source of Vitamin C? What is a good source of Vitamin D? What is a good source of Vitamin A? Water Why do we need water? Water is essential for life. Although it is possible to live without food for several weeks; without water we would die in a few days. We need water to dilute and help dispose of the body wastes and toxins in our system. Water is needed to move the nutrients, wastes, and blood cells along in the bloodstream. If water is not available for these functions, we must take it in. Our body signals its need for water by the sensation of thirst. 6

7 Water Loss Where can we get water? When we lose water by sweating to keep cool, there is an increase in our desire to drink. Fevers, vomiting, diarrhea, or the use of antihistamines to control allergies, all cause water to be lost from the body and thus increase our thirst. The largest amount of water passes out of the body as urine, heavily charged with dissolved wastes. Some water is lost when solid wastes are excreted. Water is lost by evaporation from the skin to assist in cooling the body, and from the lungs in expired air. Some foods, such as fruit and vegetables, are composed primarily of water. Watermelon is about 90 percent water, and lettuce has an even higher percentage of water content. Fibre What does fibre do? Fibre can NOT be digested. It will remain in the digestive tract until elimination. Fibre contains cellulose, lignin, polysaccharides, and pectins. We lack the specific enzymes that break down these substances. Fibre helps hold water in the large intestine by combining with the materials present. As a result, it conserves water and prevents fecal matter from drying out. In this way, it acts to prevent constipation. Diets low in fibre can increase the potential for gallstone formation, appendicitis, and coronary heart disease. Sources of Fibre Sources of Fibre The foods that contain the richest sources of dietary fibre for their mass are cereals which have not been highly processed. Green vegetables and fruits provide the least amount of fibre. They do supply fibre, but must be eaten in large amounts to satisfy the body s fibre requirements The process by which white flour is produced removes the valuable bran component of grain. Whole wheat bread is made from flour that has not been refined as much and, therefore, has not lost its fibre content. When breads are described as being enriched or restored, this usually means that some of the vitamins and minerals, which were lost during processing, have been replaced. It does not mean that any of the fibre or certain amino acids, which where also lost, have been replaced. 7

8 The Four Food Groups The Four Food Groups Every Day you need: Meat, fish, and alternatives Fruits and vegetables Milk and milk products Bread, grains, and cereals Dairy Products 3 to 4 servings Provides you with Calcium for bones and teeth Protein for tissues building and repair Ribofalvin for production of enzymes Vitamin A for healthy skin and hair Vitamin D for absorption of calcium The Four Food Groups The Four Food Groups Fruits and Veggies 4 to 5 servings (at least two vegetables) Provides you with: Vitamin A for healthy skin, good night vision, bone growth, infection prevention Vitamin C fights infections, promotes wound healing Minerals folic acid, helps form and break down amino acids Meat, Fish, and Alternatives 2 servings Provides you with Protein for building and repair of tissues an growth Iron for blood hemoglobin Riboflavin for healthy skin and eyes B6 and B12, which help with protein metabolism and the nervous system The Four Food Groups Carbohydrates Bread, pasta, cereals, grains 3 to 5 servings Provides you with Thiamin helps appetite and nervous system Carbohydrates for energy Iron for hemoglobin to carry oxygen Problems associated with unhealthy eating habits Obesity High Cholesterol Malnutrition 8

9 Obesity in Canada Obesity in Canada In Canada, more than 6 million people between 20 to 64 years old are overweight and another 2.8 million are obese. Together they represent 47% of the Canadian adult population. The prevalence in children is even more alarming. In 1998/99, the overweight and obesity rates among children ages 2 to 11 years old were 37% and 18%, respectively, compared to 35% and 15% for adults. According to the Heart and Stroke Foundation of Canada (2003), "the increasing number of overweight and obese Canadians now poses one of the greatest threats ever to public health in this country". Overweight and obesity are caused by energy imbalance. There are many contributing factors - diet is one of them as excessive calorie intake leads to weight gains. B.C. has the lowest percentages, followed by Quebec. With 15.9% obesity and 33.2% overweight, Alberta is above the national average. The four Atlantic Provinces have the highest proportions of overweight/ obese population. Obesity in Canada What can cause us to become obese? Some research has been done to quantify the economic impact of obesity. It is estimated that direct costs of medical treatments attributing to obesity were $1.8 billion in Canada in 1997 and US$75 billion in the US each year. (Birmingham, 1999; Finkelstein, 2004). Cardiovascular diseases (CVDs), diabetes, arthritis, sleep and breathing disorders, depression, and cancer are some of the diseases identified to have close associations with obesity (Food and Drug Law Institute, n.d.). Poor Habits Eating and multitasking Picking easy foods Fast Paced Life Style Skipping meals Binge eating Lack of exercise Lack of sleep Media and Advertisements Being an Informed Consumer How does the media influence us? Brand Game! Advertisements Body Image Problems Media Influences and Eating Disorders Unrealistic Body Types Dove Evolution Clip Eating Disorders Anorexia Fear of gaining weight Distorted self image Starvation: Individuals stops eating, diet is severely lacking Bulimia Fear of gaining weight Distorted self image Person binges on food or has regular episodes of overeating and feels a loss of control. The affected person then uses various methods -- such as vomiting or laxative abuse -- to prevent weight gain 9

10 Body Image Article Read it and answer the following questions What two components make up your body image? What is body hate? What are the four factors that contribute to body image? How does Barbie and GI Joe affect our body image? What percentage of women are actually capable of achieving the proportions of the typical woman s body we see in advertisements? What does it mean to be a critical viewer? How can you promote a healthy body image with your friends and family? 10