Units 1,3,4,5-Overview, Carbohydrates, Lipids & Proteins.pptx.pdf

King Khalid University College of Nursing Course Syllabus Course Name: Nutrition (326COMM-3) Nutrition(326COMM-3) Dr.Premalatha Associate Professor  Contents 1. Introduction in basics of nutrition 2. Sources and classification of food 3. Macronutr...

King Khalid University College of Nursing Course Syllabus Course Name: Nutrition (326COMM-3) Nutrition(326COMM-3) Dr.Premalatha Associate Professor  Contents 1. Introduction in basics of nutrition 2. Sources and classification of food 3. Macronutrients (carbohydrates – fats – proteins) (food sources, functions, requirements, and disorder in metabolism) Objectives By the end of this lecture, the student will be able to Define nutrition and dietetics Mention the sections of the nutrition List the Specific nutritional diseases Enumerate the classification of foods Mention the composition and functions of Protein Identify the sources of the Protein Use the methods of evaluation of protein in the body Diagnose the PEM Enumerate the classification of fat and fatty acids Differentiate Saturated and unsaturated fatty acids  Nutrition Nutrition may be defined as the science of food and its relationship to health. It is concerned primarily with the part played by nutrients in body 1. Growth 2. Development and 3. Maintenance 1. The word Nutrient or "food factor" is used for specific dietary constituents such as proteins, vitamins and minerals. 2. Dietetics is the practical application of the principles of nutrition; it includes the planning of meals for the well and the sick. 3. Good nutrition means "maintaining a nutritional status that enables us to grow well and enjoy good health"  The subject of nutrition is very extensive dealt with in five sections: 1. Dietary constituents, 2. Nutritional requirements, 3. Assessment of nutritional status, 4. Nutritional problems in public health 5. Nutrition program Protein, carbohydrate and fat had been recognized early in the 19th century as energy-yielding foods and much attention was paid to their metabolism and contribution to energy requirements.  Specific nutritional diseases were identified such as Protein energy malnutrition, Endemic goitre, Nutritional anaemia, Nutritional blindness and Diarrhoeal diseases. Science of nutrition was extending its Influence into other fields 1. Agriculture, 2. Animal husbandry, 3. Economics and 4. Sociology.  Nutrition also associated 1. Infection, 2. Immunity, 3. Fertility, 4. Maternal and child health and 5. Family health Dietary factors affect in non- communicable diseases such as 6. Coronary heart disease, 7. Diabetes and 8. Cancer. CLASSIFICATION OF FOODS 1. Classification by origin Foods of animal origin Foods of vegetable origin.  Classification by chemical composition 1) Proteins 2) Fats 3) Carbohydrates 4) Vitamins 5) Minerals. Classification by predominant function 1) Body-building foods, e.g., milk, meat, poultry, fish, eggs, pulses, groundnuts, etc. 2) Energy-giving foods, e.g., cereals, sugars, roots and tubers, fats and oils. 3) Protective foods, e.g., vegetables, fruits, milk. Classification by nutritive value 1) Cereals and millets 2) Pulses (legumes) 3) Vegetables 4) Nuts and oilseeds 5) Fruits 6) Animal foods 7) Fats and oils 8) Sugar 9) spices 10) Miscellaneous foods. NUTRIENTS Are organic and inorganic complexes contained in food. There are about 50 different nutrients Each nutrient has specific functions in the body. Most natural foods contain more than one nutrient.  Macronutrients These are proteins, fats and carbohydrates which are often called "proximate principles" because they form the main bulk of food. Micronutrients These are vitamins and minerals. they are required in small amounts vary from a fraction of a milligram to several grams. PROTEINS are of the greatest importance in human nutrition. are complex organic nitrogenous compounds. They are composed of 1. carbon, 2. hydrogen, 3. oxygen, 4. nitrogen and 5. sulphur in varying amounts.  Some proteins contain phosphorus and iron and other elements. Proteins differ from carbohydrates and fats in that they contain nitrogen, this usually amounts to about 16 per cent. Constitute about 20 per cent of the body weight in an adult. Essential amino acids Proteins are made up of smaller units, called amino acids. 20 amino acids are needed by the body, of which 9 are called "essential" because the body cannot synthesize them in enough amounts and they must be obtained from dietary proteins. (leucine, isoleucine, lysine, methionine, phenylalanine, threonine, valine, tryptophan and histidine). Non-essential amino acids Include (arginine, asparaginic acid, serine, glutamic acid, proline and glycine). Both essential and non-essential amino acids are needed for synthesis of tissue proteins A protein is said to be "biologically complete" if it contains all the EAA in amounts corresponding to human needs. When one or more of the EAA are lacking, the protein is said to be "biologically incomplete The quality of dietary protein is closely related to its pattern of amino acids.  From the nutritional standpoint, animal proteins are rated superior to vegetable proteins because they are "biologically complete". For example milk and egg proteins have a pattern of amino acids considered most suitable for humans. Proteins functions (A) body building, (b) repair and maintenance of body tissues; (c) maintenance of osmotic pressure; and (d) synthesis of certain substances like Antibodies, Plasma proteins, Haemoglobin, Enzymes, Hormones and Coagulation factors. Proteins are connected with the immune mechanism of the body. Proteins can also supply energy (4 kcal per one gram) Sources of proteins ANIMAL SOURCES : Proteins of animal origin are found in milk, meat, eggs, cheese, fish and fowl. These proteins contain all the essential amino acids (EAA) in adequate amounts. Egg proteins are considered to be the best among food proteins because of their high biological value and digestibility. They are used in nutrition studies as a "reference protein", Plants SOURCES Plants proteins are found in pulses (legumes), cereals, beans, nuts, oil-seed cakes, etc. They are poor in EAA. Supplementary action of proteins Man derives protein from different sources; their proteins supplement one another and provide a protein comparable to animal protein in respect of EAA. (Vegetarian) Evaluation Through of proteins Amino acid content (biological value) Digestibility coefficient “The digestibility of a nutrient is measured as the difference between the amount of nutrient ingested minus the amount of nutrient excreted in the feces, expressed as a percentage of the nutrient ingested: 100 x (intake - excreted)/intake.)” Suitability to meet the protein needs of the body. Net protein utilization “proportion of ingested protein that is retained in the body under specified conditions for the maintenance and/or growth of the tissues” Principal Features of Severe PEM (ALWAYS PRESENT ) Muscle wasting : obvious sometimes hidden by edema and fat Fat wasting severe loss of subcutaneous fat. Weight for height : very low but may be masked by edema Mental changes. Sometimes quiet and apathetic Irritable, moaning.  FATS Fats are solid at 20C Called "oils" if they are liquid at that temperature. Fats and oils are concentrated sources of energy. Fats Classified as : (a) Simple lipids, e.g., triglycerides (b) Compound lipids, e.g., phospholipids(These can be formed in the brain and central nervous system, and function as energy-storage molecules and chemical messengers) (c) Derived lipids, e.g., cholesterol (fatty acids that can originate from the simple and compound lipids by means of hydrolysis.) Fatty acids Fats yield fatty acids and glycerol on hydrolysis. Fatty acids are divided into Saturated: fatty acids such as lauric, palmitic and stearic acids, and Unsaturated: fatty acids which are further divided into monounsaturated (MUFA) (e.g., oleic acid) and poly-unsaturated fatty acids (PUFA) (e.g., linoleic acid and a- linolenic acid). The poly-unsaturated fatty acids are mostly found in vegetable oils, and The saturated fatty acids mainly in animal fats.  Essential fatty acids Essential fatty acids are those that cannot be synthesized by humans, They can be derived only from food. The most important essential fatty acid (EFA) is linoleic acid, which serves as a basis for the production of other essential fatty acids (e.g., linolenic and arachidonic acids). Sources of fats classified as : ANIMAL FATS: butter, milk, cheese, eggs, and fat of meat VEGETABLE FATS: groundnut, sesame, coconut, etc. See Table Energy, protein, fats and minerals requirements 1.https://www.fao.org/3/y5022e/y5022e04.htm 2.https://www.ncbi.nlm.nih.gov/books/NBK56068/table/su mmarytables.t4/?report=objectonly 3.https://www.ncbi.nlm.nih.gov/books/NBK545442/table/ appJ_tab1/?report=objectonly Eg. If your calorie intake is 2000 Calories, find the grams of fat, carbohydrate and protein that should be in your daily intake.  The total quantity of invisible fat and its fatty acid composition depends on the kind of diet consumed. Vegetable oil used in cooking is the major type of visible fat consumed. Functions of Fats Fats have always been equated with calories. They are high energy foods, providing as much as 9 kcal for every gram. Spare proteins from being used for energy. Fats serve as vehicles for fat-soluble vitamins. support viscera such as heart, kidney and intestine; and fat under the skin provides insulation against cold. Poly-unsaturated fatty acids recognized as "local hormones"; they play a major role in controlling many of the physiological functions of the body such as: Vascular haemostasis, Kidney function, Acid secretion in stomach, Gastro-intestinal motility, Lung physiology and Reproduction. Cholesterol is essential as a component of membranes and nervous tissue and is a precursor for the synthesis of steroid hormones and bile acids. Thus fats and oils are useful to the body in several ways. Trans-fatty acids Partial hydrogenation, of poly-unsaturated fatty acids (PUFAS) create trans fatty acids. Trans-fatty acids render the plasma lipid profile by elevating LDL cholesterol and decreasing HDL cholesterol. Intake of trans-fatty acids increases the risk of coronary heart disease. It takes years for trans fatty acids to be flushed from the body. Deep fried fast foods are major sources of trans-fatty What are examples of trans fats? Foods Containing Trans Fats Fast foods—including tater tots, and French fries. Some spreads—such as margarine spreads or peanut butter. Some snack foods—such as chips, crackers, and cookies. Fried foods—including fried chicken, onion rings, and nuggets. Nondairy creamer. Pre-prepared cake frostings.  Refined oils Refining is usually done by treatment with steam, alkali, etc. Refining and deodorization of raw oils is done mainly to remove the free fatty acids and rancid materials. Refining does not bring about any change in the unsaturated fatty acid content of the oil. It only improves the quality and taste of oils. Fats and disease (a) Obesity: A diet, rich in fat, can pose a threat to human health by encouraging obesity. (b) Phrenoderma : Deficiency of essential fatty acids in the diet is associated with rough and dry skin, a condition known as phrenoderma or "toad skin". Phrenoderma can be cured rapidly by food rich in EFA, along with vitamins of the B-complex group. (C) Coronary heart disease : High fat intake (i.e., dietary fat representing 40 per cent or over of the energy supply and containing a high proportion of saturated fats) has been identified as a major risk factor for CHD (D) Cancer: diets high in fat increase the risk of colon cancer and breast cancer. (e) Others: The skin lesions of kwashiorkor and those induced by EFA deficiency are similar. The possible association between the skin lesions of kwashiorkor and EFA deficiency The WHO/FAO Expert Group set the following ranges for population nutrient goals (% of Energy) Total fat, 15-30 (at least 20%E (energy) and cholesterol less than 300 mg a day