Nutrition By Dr. Aliaa Makki Community physician
References:*Kruse’s nutrition & diet therapy 12th edition*Foundations & Clinical Applications of Nutrition 2nd ed.*Introduction to Clinical Nutrition*WHO publications*Oxford handbook of nutrition & dieteticsObjectives:
By the end of this lecture you will be able to; Know the relevant definitions. Understand the; food & diet, staple food. Memorize the; main food groups, balanced diet, food guide pyramid for a healthy adult (male & female).Community nutrition:
Public health nutrition efforts to prevent nutrient deficiencies including individuals & families below certain income. The nutritional status of our community is a reflection of our individual nutritional health.Nutrition:
Is the branch of science that deals with the processes by which components of food are made available to an organism for meeting energy requirement, building, growing, maintaining tissues & maintaining the organism in optimum functional health .Clinical nutrition: Is a medical specialty dealing with the relationship between disease & nutrition. Acute & chronic illness is caused by deficiencies or excesses of dietary components.
Role of nutrition: It focus on the way to organize our lives so that we can more easily follow an eating pattern designed to enhance health status. Consuming a diet based on lower fat , higher fibers &moderate caloric intake which is the new challenge to change our life style. Lifestyle=pattern of behavior
The study of nutrition deals with; 1-Food composition & nutritive value of foods. 2-Quantitative & qualitative values required in different age group & development level in life & in different physical activity, physiological & psychological levels & affected by income & social levels. 3-Digestion, absorption, transport, metabolism & excretion of the food taken.
Metabolism: All cells have two major general functions; Energy generation. Energy utilization for growth &/or maintenance.
Anabolism: processes in which large molecules (such as protein) are biosynthesized from small nutrients (such as amino acid), it requires energy (ATP). Catabolism: is the degeneration of large molecules to smaller ones. It serves to capture chemical energy (ATP) from the degeneration of energy rich molecules.
In adult there is a regulated balance between anabolic (synthetic) & catabolic (degenerative) processes. In the growing child, input of nutrients & anabolism exceed catabolism leads to tissues growth. In the aging process or in wasting diseases, the catabolic processes exceed anabolic ones.
Malnutrition: Is a condition characterized by inappropriate quality, quantity, digestion, absorption or utilization of ingested nutrients i.e. an imbalanced nutrients & or energy intake. It includes; 1-Undernutrition: low food intake (calorie deficiency) leading to growth suppression or other deficiency signs. 2-Overnutrition: to consume too much food &/or single nutrients leading to specific toxicities.
Food: all solid or liquid materials that taken by mouth to the digestive tract & utilized in the body to maintain &build the body tissues Diet: all nutrient that enter the body orally or parentrally e.g. Glucose water & normal saline as well as parenteral feeding of amino acids & fatty acids in addition to oral food.
Staple food:
Is one that form the basis of the diet in term of both quantity &frequency of consumption & provides the highest proportion of energy. It is vary with the geographical region, eg. Cereals; rice, wheat,--Nutrients: are those chemical substances needed for growth, maintenance or repair of normal cells both in human or animals & plants. There are 45-50 chemical entities are known to be required by humans either performed by food or added as chemical supplements.
The foods are classified into; 1-Organic compounds e.g. protein, carbohydrates, fat& vitamins. 2-Inorganic compounds e.g. water (called silent nutrient)& minerals. Dietary fibers :although not classified as nutritionally essential, but it is important in maintaining good health.
The basic food groups; Group Food Major nutrient 1-Milk gp milk &diary products Ca., protein &B2 2-Meat gp meat, fish, poultry, eggs, protein, fat, meat substitutes; peas, Fe &minerals beans 3-Bread & bread, cooked cereals, CHO,V.B ,Fe cereal group dry cereals, rice, pasta, potatoes 4-Vegetable gp green &yellow vegetable minerals ,vit., CHO,& water 5-Fruits group all variety of fruits V.C,V.A &its precursors 6-Fats &oils cream, butter, olive oil,--- fat (energy), fat sol. Vit. 7- Water water
Balanced diet:
Is a diet that include all these above nutrients in adequate & appropriate amount. 1-Energy foods; Cereals, Starchy vegetables (potato), Fats & oils, Sugars. 2-Body building foods; Milk &dairy products, legumes, meat group. 3-Protective foods; Vegetables, fruits.Body Constituents: The human body composed of; 62% H2O. (more in infants & children). 16% protein. 15% fat (it differ from obese to thin person). 1% CHO. 6% minerals (Ca., P, Fe). Trace of vitamins.
Constituent of food : (nutrients) are divided into:1-Essential nutrients: must be supplied from outside the body (i.e. from the diet) because the body cannot synthesis them at all or it cannot synthesis them in sufficient quantities for the normal requirement of the body. Any inadequate intake of essential nutrients will lead to a deficiency disease.2-Non –essential nutrients: they are nutrients that the body can synthesize them so their presence in the diet is not very essential, so the inadequate intake will not lead to deficiency disease.
The essential nutrients: Food category Essential nutrient CHO - Glucose Fat or lipids - Linoleic acid, Linolenic acid Protein -Amino acid: Lycin, leucine, Isoleucine, Threonine, Phenylalanine, Tryptophane, Methionine, Valine, Arginine (ess.for infants), Histidine (may be ess.) Vitamins -Fat soluble; V.A (retinol), V.E( tocopherol), V.K
-Water soluble vit.; V.C (ascorbic acid), V.B1(thiamine), V.B2(riboflavin), Niacin (nicotinic acid), V.B6(pyridoxine), Pantothenic acid, Biotin, Folacin (folic acid), V.B12(cobalamine) Minerals -Macrominerals; Ca, Na,K ,Mg (>100mg /day) -Microminerals; Fe, Zn, I, Se, Mn(<100mg/ day)
Daily Food Guide Pyramid For A Healthy Adult (Male &Female)
Milk gp(2-3) servings
Meat gp(2-3) servingsSweets& lipids
fruit gp(2-4) servings
Bread& cereal gp(6-11) servings
Vegetables(3-5) servings
Daily Food Guide pyramid: *Milk group 2-3 servings *Meat group 2-3 servings *Fruits 2-4 servings *vegetables 3-5 servings *Bread group 6-11 servings *Sweets& lipids as minimum as possible **Serving= portion size.