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Download Nutrition Chapter 1 Inroduction to Nutrition
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Introduction to Nutrition Chapter 1 Learning Objectives Explain what nutrition is and why it should be important to you on a personal level, and as a culinary/foodservice professional. Identify three food groups we don’t eat enough of, and two food groups we eat too much of. Define flavor and explain how it involves all five senses. Discuss five factors that influence what you eat. Define kilocalories; identify the three factors that influence the number of kcalories you use every day; and explain the effect of the following on basal metabolic rate: gender, age, exercise, and growth. Name the six classes of nutrients and their characteristics. Learning Objectives (cont’d) Give two examples of foods that are nutrient dense and two that are empty kcalorie foods. Explain why you chose these foods. Describe four characteristics of a nutritious diet. Identify a given food as a whole food, processed food, enriched or fortified foods, and/or organic food. Explain what is meant by Recommended Dietary Allowance, Adequate Intake, and Tolerable Upper Intake Level of a nutrient. Explain how food is digested and absorbed in the gastrointestinal tract. To run a sustainable facility, list five things chefs are doing in the kitchen and five things managers are doing in the dining room and production areas. Nutrition and You More then just diet ◦ Must also maintain a healthy weight, engage in physical activity, get enough sleep and not smoke Nutrition ◦ The science that studies how nutrients interact with your body, physically and mentally Nutrients ◦ the nourishing substances in food that provide energy and promote the growth and maintenance of the body. Looks at how nutrients and other substances in food relate to health and disease. Explores why you choose the foods you do – in other words, the type of diet you eat. Diet and Disease Our choice of diet strongly influence whether we will get certain diseases such as: ◦ Heart disease ◦ Cancer ◦ Stroke U.S. Epidemic: Overweight and Obesity ◦ 72% of men and 64% of women are overweight or obese. ◦ 32% of children ages 2 to 19 years are overweight or obese. Diet and Disease What contributes to obesity? Diet and inactivity. What can obesity lead to? Diabetes, heart disease, high blood pressure. Eating healthy can reduce your risk of: ◦ Heart disease ◦ High blood pressure ◦ Diabetes ◦ Several types of cancer Healthy Foods* Fruits Vegetables Whole grains Beans and peas Fat-free of low-fat dairy Lean meats, poultry Seafood * All with minimal solid fat, sugar, or sodium Nuts and seeds How the US Diet Compares to Recommendations Why You Eat the Foods You Do Flavor Other aspects of food (cost, convenience, nutrition) Demographics Culture and religion Health Social and emotional influences Marketing and the media Environmental concerns Flavor Includes taste, smell, texture or mouthfeel, temperature, and sounds. Flavor is a combination of all five senses (taste, smell, touch, sight, and sound). The most important consideration when choosing something to eat is taste. ◦ You have about 10,000 taste buds on your tongue, cheeks, throat, and roof of the mouth. ◦ Taste buds for each sensation are scattered around the mouth. ◦ Children under six have more taste buds, and adults over 50 start to lose taste buds. ◦ Young children have more taste buds, so they can often be picky eaters. Five Primary Taste Sensations Sweet Sour Salty Bitter Umami Umami ◦ Umami provides a savory, sometimes meaty, sensation. ◦ Umami taste receptor is very sensitive to glutamate—an amino acid found in protein such as meat, fish, and milk, and in the flavor enhancer MSG. ◦ Umami flavor increases when salt is added (ketchup, soy sauce, fish sauce). The heat of hot peppers is felt not by the taste buds but by pain receptors in the mouth that sense heat. Smell Smell is very important to taste. ◦ Most of taste is actually based on what we smell ◦ This explains why when we are stuffy, we cannot taste Receptors in your nose can distinguish among about 10,000 scents. Texture or Mouthfeel Textures that people like: Crispy Juicy Creamy Tender Firm Crunchy Textures people generally don’t like: Tough Crumbly Lumpy Soggy Watery Textures influence whether you like the food, and also tells you whether the food is fresh. Sight and Sound You eat with your eyes. Color is very important ◦ it tells you about the flavor and quality of food. For eye appeal, consider color, size, shape, consistency, and arrangement. Eye appeal is especially important for cold foods. ◦ Cold numbs the taste buds and therefore taste is muted Sounds—the sizzle of fajitas—stimulate appetite along with sight. Other Aspects of Food Food cost ◦ We live on a budget and prices can fluctuate Convenience ◦ Time is always a factor Availability ◦ Seasonal items Familiarity ◦ What we grew up eating Habits ◦ Cereal for breakfast, popcorn at the movies, chicken soup when sick Nutrition ◦ Stronger nutritional labeling Culture and Religion Culture is the behaviors and beliefs of a certain social, ethnic, or age group ◦ What foods are eaten where, weddings Religion can affect day-to-day food choices. ◦ Kosher and Halal, Lent, etc Other Influences on What You Eat Health concerns (such as dieting) Social influences (peer pressure) Emotional influences (comfort foods) Marketing and the media Environmental concerns What are Kilocalories? A measure of the energy in food One kilocalorie raises the temperature of one kilogram of water one degree Celsius. Abbreviated as kcalorie or kcal. When you hear “calorie,” it is really a kilocalorie. ◦ 1 kilocalorie = 1000 calories ◦ If we were to use true “calories” the numbers would be cumbersome to keep track of Instead of a 2000 kcal diet, we would have a 2,000,000 calorie diet Number of Kcalories Needed The number of kcalories needed is based on three factors: 1. Basal metabolism (about two-thirds of total energy needs for individuals who are not very active) 2. Physical activity can range depending on activity 3. Energy used to digest and absorb food (about 10% of total energy needs) BMR depends on: Gender Height Age Temperature Growth Fever and stress Exercise Smoking and caffeine Sleep Physical activity accounts for 25 to 40 percent of your total energy needs. What Are Nutrients? Carbohydrates (4 kcal/g) Fats (9 kcal/g) Proteins (4 kcal/g) Vitamins Minerals Water No kcalories in vitamins, minerals, or water. Alcohol supplies 7 kcal/g but is NOT a nutrient because it does not promote growth or maintenance of the body. Macronutrients vs. Micronutrients Macronutrients The body needs these in greater amounts, usually measured in grams or ounces Carbohydrates Fats Proteins Micronutrients The body needs these in smaller quantities, usually measured in micrograms Vitamins Minerals Carbohydrates A large class of nutrients, including: ◦ Sugars ◦ Starch ◦ Fibers Sugars and starches function as the body’s primary source of energy. Fats and Oils Fats and oils provide a rich source of energy. Examples: ◦ Butter ◦ Margarine ◦ Vegetable oils ◦ Mayonnaise ◦ Salad dressings Protein Only about 15% of total kcalories should come from protein. Protein is part of every cell, tissue, and organ in the body. Animal foods are good sources of proteins. Proteins are present in smaller quantities in plant foods such as grains, beans, and vegetables, but they are not complete Vitamins and Minerals Non-calorie nutrients found in a wide variety of foods that are essential to: ◦ regulate body processes. ◦ maintain the body. ◦ allow growth and reproduction. Water Inorganic nutrient that makes up just over half of the body’s weight Plays a vital role in all bodily and metabolic processes ◦ Supplies the medium in which chemical change of the body occur Aids digestion and absorption, circulation, and lubrication of body joints Your body is about 60% water and 20% to 25% fat. Essential Nutrients Essential nutrients either cannot be made in the body or cannot be made in the quantities needed by the body. ◦ Examples are vitamins and minerals. What is Nutrient Density? Nutrient density is a measure of the nutrients provided in a food per kcalorie of that food. ◦ How many kcalories the food provides versus how many nutrients it provides Empty-kcalorie foods provide few nutrients for the number of kcalories they contain. Characteristics of a Nutritious Diet Adequate ◦ Provides enough kcalories, essential nutrients and fiber to keep a person healthy Balanced ◦ Provides kcalories, essential nutrients and fiber in the right proportions Moderate ◦ Avoids excessive amounts of kcalories or any particular food group Varied ◦ A wide variety of foods from each food group How to Recognize Whole, Processed, Fortified, and Organic Foods Whole foods: Foods pretty much as we get them from nature (eggs, fresh fruits and vegetables, beans and peas, whole grains, fresh meat, milk) Processed foods: food prepared using milling, cooking, freezing, canning, dehydrating, or culturing with bacteria (bread, cookies, cereals, sauces, soups, baking mixes, frozen entrees, pasta, snack foods) Enrichment and Fortification Fortification: a food is fortified when nutrients are added that were not present originally, or nutrients are added that increase the amount already present. ◦ Example: calcium in orange juice Enrichment: a food is enriched when nutrients are added to replace nutrients that were lost in processing. ◦ Example: breads enriched with iron and several B vitamins Organic Foods Organic food is produced without using most: ◦ Conventional pesticides ◦ Petroleum-based fertilizers or sewage sludge-based fertilizers ◦ Bioengineering ◦ Ionizing radiation Organic farms must be inspected annually. All organically raised animals may not be given hormones or antibiotics, and must have access to a pasture. Labeling of Organic Foods 100% organic 95% organic These can use USDA Organic seal. 70% organic ingredients: These can use the phrase “made with organic ingredients.” Digestion, Absorption, and Metabolism Digestion: Process by which food is broken down into its components in the gastrointestinal tract with the help of digestive enzymes. Absorption: The passage of digested nutrients through the walls of the intestines or stomach into the blood, where they are transported to the cells. Metabolism: All the chemical processes by which nutrients are used to support life. ◦ Catabolism- breaking down of substances Breaking sugar down to monosaccharaides ◦ Anabolism- building up of substances Building bone tissue What Happens When You Eat? The Gastrointestinal Tract The Digestive System Mouth – Oral Cavity • Tongue and teeth help chew food (32 adult teeth) • Saliva contains digestive enzymes and lubricates the food to move further along Tongue rolls chewed food into a ball to be swallowed. From Mouth • The food moves from the mouth through the to Esophagus pharynx to the esophagus. • Peristalsis- involuntary motion Stomach • Food passes from esophagus into the stomach. • Stomach holds about 4 cups of food. • Makes hydrochloric acid that helps in protein digestion and destroys bad bacteria. • Fatty foods leave stomach after carbohydrates and protein. The Digestive System Small Intestine • Nutrients are still being digested. • Site of most nutrient absorption. • Most nutrients pass through villi into blood vessels—or are transported to the blood. • Nutrients travel in the blood throughout the body where they can enter the cells. Large Intestine • Connects small intestine to the rectum. • Receives waste products of digestion and passes them on to rectum. • Absorbs water, some minerals, and a few vitamins (such as vitamin K) made by bacteria residing there.
