Introduction to Nutrition GESH220 Fall 2023 PDF

INTRODUCTION TO NUTRITION GESH220 - Fall 2023  W H AT I S N U T R I T I O N ? The science that links fo o ds to health and disease. Includes the pro cesses by w hich the hum an organism ingests, digests, abso rbs, transpo rts, and excretes fo o d substances FOOD VS DIET Food Any subst...

INTRODUCTION TO NUTRITION GESH220 - Fall 2023  W H AT I S N U T R I T I O N ? The science that links fo o ds to health and disease. Includes the pro cesses by w hich the hum an organism ingests, digests, abso rbs, transpo rts, and excretes fo o d substances FOOD VS DIET Food Any substance that the body can ingest and assimilate Used to enable the maintenance of life and growth A source of nutrients Diet The food that a person consumes (eating and drinking) usually. WHY STUDY NUTRITION? How Powerful is the Diet In Preventing Diseases? Nutrition profoundly affects health and well-being within the range set by genetic inheritance NUTRITION AND DISEASE Not all diseases are equally influenced by diet Some are purely genetic, some may be influenced by diet, some are purely dietary MALNUTRITION Disease/condition highly nutrition related Caused by: Excess fo o d energy or nutrient intake (overnutrition) Deficient fo o d energy or nutrient intake (undernutrition) Nutrient im balance  A continuo us deterio ratio n in the ability of the Lebanese ho useho lds to access fo o d and other basic needs w as no ted during March -April 2021. Forty seven percent of the ho useho lds repo rted NUTRITION having challenges in com pariso n to 43 percent repo rted in Novem ber-Decem ber 2020, natio nally. SECURITY IN The pro po rtio n of Lebanese ho useho lds facing LEBANON fo o d sho rtage continues to increase during the repo rting perio d 58 percent repo rted facing fo o d sho rtages in the 14 days prio r to the survey com pared to 55 percent in Novem ber-Decem ber 2020. https://reliefweb.int/report/lebanon/lebanon-m-vam-vulnerability-and-food-security-assessment-march-april-2021 - Accessed January 2022  Undernutrition: -Deficiency of nutrients or Energy. STAT E S O F N U T R I T I O N Overnutrition - Excess of nutrients or Energy The states of nutrition Over Nutrition Under Nutrition Desirable Nutrition Reduced Biochemical Obesity function Clinical signs and Serious diseases symptoms NUTRIENTS NUTRIENTS VS FOOD Food: any substance that the bo dy can take in and assim ilate that w ill enable it to stay alive and to grow. It is the carrier of energy & no urishm ent Nutrients: com po nents of fo o d that are vital fo r the bo dy’s functio ning, grow th and m aintenance Diet: The foo ds a perso n usually eats and drinks HUMAN BODY & FOOD Sam e m aterial different arrangem ent NUTRIENTS 6 classes, 4 of Classified as Components of which are organic macro or food being: (contain carbon) micronutrients: Macronutrients: Indispensable to Water, the body’s Carbohydrate, functioning Protein, & Fat Provide energy; Micronutrients: promote growth; Vitamins & repair & Minerals maintenance  THE HUMAN BODY AND ITS FOODS The body uses energy → Com es indirectly from the sun Six kinds of nutrients are fo und in Foo d [4 are organic (co ntains Carbo n) / 3 provide Energy] Body needs Body needs are large MACRONUTRIENTS MICRONUTRIENTS are sm all ELEMENTS IN THE SIX CLASSES OF NUTRIENTS  ENERGY YIELDING NUTRIENTS The nutrients the body can use as energy source are Energy Nutrient Amount of Energy carbohydrates, fats (lipids) and proteins ✓ Energy Unit Carbohydrate 4 Cal/g ✓ Kilocalorie = kcalorie = Calorie Fat (Lipid) 9 Cal/g ✓Used to easure Energy in Food ✓Amount of heat needed to raise the temperature of 1 kilogram of Protein 4 Cal/g water by 1oC Alcohol 7 Cal/g Water, Vitamins and minerals do NOT yield energy Alcohol is NOT considered a nutrient CA LO R I E CA L C U L AT I O N How many calories in a typical deluxe hamburger sandwich? -Carbohydrate: 37 grams (37 x 4= 148 kcal) -Fat:33 grams (33x 9= 297 kcal) -Protein: 30 grams (30 x 4= 120 kcal) Total calories=156+288+120=565 kcal E X A M P L E S : 1 T B S P C H O C O L AT E S P R E A D 5 g total fat 10 g Carbohydrates 2 g Proteins 10 mg Sodium Total Calories = ?  W H Y D O W E N E E D E N E R GY ?.... M E TA B O L S I M Sum of all chemical reactions in the body: Enzymes: Proteins that catalyze metabolic reactions in the body. They are specific for their substrate and for Anabolism : Catabolism: break the chemical reaction synthesis reactions down reactions that they catalyze (require energy) (release energy)  The Challenge Of Choosing Foods The variety of foods available to the consumer today makes it harder, rather than easier to plan a nutritious diet Selecting foods that support good health requires knowledge about caloric density, and nutrient and non-nutrient contents of foods Even more importantly is the knowledge of how to combine different food groups into a nutritious diet H OW, E X ACT LY, CA N I R E C O G N I Z E A N U T R I T I O U S D I E T ? A nutritious diet is actually a common mode of consumption with 5 characteristics: Have different fo o d cho ices each day to ensure intakes of all nutrients Stay m o derate w ith salt, sugar & lipids Foo ds sho uld contain the right am o unt of energy to m aintain a healthy w eight- adjusted to energy expenditure Do no t overem phasize one nutrient or fo o d type at the expense of ano ther Provides eno ugh of the essential nutrients A well-planned diet is adequate in nutrients, balanced in food types, provides E to balance that expended by activity, is moderate in unwanted nutrients, and offers a variety of nutritious foods. Fa c t o r s A f f e c t i n g F o o d C h o i c e s Social needs Social network Psychological of family needs and friends Food flavor, texture, Food customs and appearance and preferences culture Food availability Food cost Education, Food marketing occupation, and income Health and nutrition Routines concerns, knowledge, and and beliefs habits Lifestyle Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. How Do we Judge Which Foods are Most Nutritious? By m e asu r in g th e ir nutrient density Foods That offer the most nutrients per calorie count are considered the most nutritious  NUTRIENT DENSITY Nutrient density is used to determine the nutritional quality of a food Foods rich in nutrients relative to their energy contents are nutrient dense Amount of Nutrients Amounts of Calories Hence, the more nutrients and the fewer the Calories, the higher the nutrient density Comparison Nutrient Density Empty Calories? Empty calories =Very low nutrient density  CA N W E G O W I T H O U T FO O D A N D L I V E O N LY F RO M SUPPLEMENTS? Nutrition studies the nutrients that humans need to survive. In principle, Elemental diets based on supplements are only given to seriously ill people only to "survive" because they do not promote growth or health. They are only needed for life support in critical conditions, in the event of nutritional deficiency, infections, or serious injuries (burns) for a short period of time. Dietary supplements are not necessary for healthy people with a healthy diet. DIETETIC SUPPLEMENTS Pills, liquids, or powders that contain purified nutrients or other ingredients Cannot be used in place of food  Real Food is Superior to supplements The digestive tract is a dynamic system that responds to the food it receives (Physical contributions) Food sight, smell and taste. If a person is fed through a vein ==> atrophy of the digestive organs When the digestive tract is no longer stimulated: The body's defenses are weakened against some infections. Food provides physical and emotional comfort. (Psychological contributions) Foods are chemically complex In addition to nutrients, foods contain non-nutrients Components other than the 6 nutrients found in food which have biological activity in the body. Some foods offer beneficial non-nutrients called “phyto-chemicals” Components of NonNutrients in foods of plant origin that have biological activity in the body. Give color, taste, etc. to food Several can have an effect on health by reducing disease Capsaicin: a compound in pepper that gives Examples burning taste with heart health benefits Allicin: a compound in garlic that gives pungent flavor and has antimicrobial properties Tannins: Antioxidants found in wine and tea that may prevent some cancers  Spotting Accurate Nutrition Information ELEMENTS OF NUTRITIONAL QUACKERY IN A NUTSHELL 1- Claim is too good to be true 2- Claims to have a secret formula 3- Makes unrealistic guarantees 4- Claims weight loss much greater than half a kilogram in a week 5- Uses “Star” testimonials Scientific Challenge One experiment does not “prove” or “disprove” anything A finding that has stood up to repeated rigorous testing may become a theory Information must be looked at with an educated eye How to Determine if a Website is Reliable? WHO? Is the owner of the website qualified to speak on nutrition (Dietitian? Physician? Other?) WHEN? When was the website updated? WHERE?.gov/.org/.edu/ WHY? selling of a product? WHAT? What is the message-beware of information that contradicts common knowledge Reliable Websites: Examples Credible Website/Scientific Databases www.lebanondiet.org www.googlescholar.com www.medlineplus.gov www.pubmed.gov www.eatright.org www.who.int www.dietitians.ca www.sciencedirect.com ww.usda.gov www.fda.org www.os.dhhs.gov www.hc-sc.gc.ca www.americanheart.org www.cancer.org www.acsh.org www.diabetes.org Who Can Speak Nutrition? Is this person qualified to speak on nutrition (credentials)? According to Lebanese law a dietitian must be licensed by the Ministry of Public Health in order to practice