An Overview of NutritionAn Overview of Nutrition: Food, Energy, and Nutrients. Dietary Standards. Nutritional Assessment An Overview of Nutrition

You Are What You Eat   Giuseppe Archimboldo, The Four Seasons, 1573

Nutrition:  Nutrition: The science of food and the nutrients and other substances they contain, and of their action in the body (ingestion, digestion, absorption, transport, metabolism and excretion). The science of food and the nutrients and other substances they contain, and of their action in the body (ingestion, digestion, absorption, transport, metabolism and excretion).

Nutrient Density

 FOOD: Products derived from plants or animals that can be taken into the body to yield energy and energy and nutrients for maintenance of life and the growth and repair of tissues Products derived from plants or animals that can be taken into the body to yield energy and energy and nutrients for maintenance of life and the growth and repair of tissues  DIET: The food and beverages a person eats and drinks. The food and beverages a person eats and drinks.

Food Choices:  Food Choices :  Personal preferences  Habit  Ethnic Heritage or tradition  Social Interactions  Availability, convenience and economy  Emotion comfort, Values, Body image.  Positive and Negative Association, Nutrition

Classes of Nutrients  The Six Classes of Nutrients:  Carbohydrates  Lipids  Proteins  Vitamin  Minerals  Water

Carbohydrates Complex Simple Fiber

Carbohydrates  Body ’ s main energy source  Foods high in complex carbohydrates are usually high in fiber; promote colon health  Simple sugars lack fiber as well as minerals and vitamins of whole foods; intake should be minimized

Lipids/Fats Essential fatty acids: linoleic & linolenic acids Saturated FatUnsaturated Fat

Lipids  Most fats can be synthesized  Essential fatty acids must be obtained from food  Fats should be about 30 percent of diet  Excess saturated fats can raise cholesterol level and contribute to heart disease

Protein (Animal and plants)

Proteins  Body cannot build eight of the twenty amino acids  These essential amino acids must be obtained from diet  Animal proteins are complete; supply all essential amino acids  Plant proteins are incomplete; must be combined

Vitamins and Minerals  Vitamins –Fat Soluble  A, D, E, K –Water Soluble  B1, B2, Niacin, B6, Folate, Pantothenic acid, B12, Biotin, C  Minerals –Calcium, Chloride, Copper, Fluoride, Iodine, Iron, Magnesium, Zinc, Phosphates, Potassium, Sodium, Sulfur

What Nutrients Do Nutrients: Provide energy Form body structure Regulate physiological processes

What Nutrients Do Lipid: Hormone Testosterone Made from cholesterol (Lipid) Regulate body process : Sperm production, secondary sex characteristics like facial hair, deep voice And increased muscle mass.

What Nutrients Do: Provide Energy  Working together, macronutrients and micronutrients help the body stay healthy.  Biochemical reactions in the body help to release the energy contained in carbohydrates, fats and proteins.  Energy is used to maintain body functions, fuel physical work and to repair the body.  If more energy is consumed than is needed, over time, body weight will increase.

What Nutrients Do: Form Structures  Most of the weight of the body is due to water, fat and protein.  Nutrients help to form and maintain the shape and structure of the body.  Proteins form ligaments and tendons that hold bones together and attach muscles to bones.  At the cellular level, lipids and proteins make up the membranes that surround cells.

What Nutrients Do: Regulate Body Processes  All the reactions that occur in the body are called metabolism.  The proper regulation of metabolism is called homeostasis.  Each nutrient plays a role in helping to maintain homeostasis.  Water helps to regulate temperature.  Protein, vitamins and minerals help to speed up or slow down metabolic reactions.

Energy Yielding Nutrients:  Energy Yielding Nutrients:  The nutrients that break down to yield.  Energy that body can use.  Carbohydrates  Lipid or fat  Protein

ENERGY:  The capacity to do the work. The energy in food is chemical energy. The body can convert this chemical energy to mechanical, electrical and heat energy.

Calorie: Unit by which energy is measured. Unit by which energy is measured. Food energy is measured in kilocalories (1000 calories equal 1 kilocalorie) K calories or kcal. Food energy is measured in kilocalories (1000 calories equal 1 kilocalorie) K calories or kcal. 1g carbohydrate= 4 Kcal 1g carbohydrate= 4 Kcal 1g protein= 4 kcal 1g protein= 4 kcal 1g fat=9 kcal 1g fat=9 kcal 1g alcohol= 7 kcal 1g alcohol= 7 kcal

Calculate the energy available from 1 slice of bread with 1 table spoon of peanut butter on it contains 16 grams carbohydrate, 7 grams protein and 9 gram of fat, then determine the percentage of k calories from fat.  16 g carbohydrates X 4 Kcal/g =64 Kcal  7gm protein X 4 Kcal/g = 28 Kcal  9g fat X 9 Kcal/g =81 Kcal  Total = 173  %of kcal from fat =81/173 X100 = 46.8%

Establishing Nutrient Recommendation RDA : Recommended Dietary Allowance (USA) RNI : Recommended Nutrient Intake (Canada) Goal : Protecting against nutrient deficiency.

Dietary Reference Intakes (DRI):  Dietary Reference Intakes (DRI):  A set values of dietary nutrient intakes of healthy people in USA and Canada. These values are used for planning and assessing diet and include:  Estimated Average requirements. (EAR)  Recommended dietary intake (RDA)  Adequate Intake (AI)  Tolerable Upper intake levels (TUIL)

Recommended Dietary Allowance (RDA):  Recommended Dietary Allowance (RDA):  The average daily amount of nutrient considered adequate to meet known nutrient needs of practically all healthy people; a goal for dietary intake by individual.

 Estimated Average Requirement: The amount of a nutrient that will maintain a specific biochemical or physiological function in half of given people of a given age or sex Group.  Deficient: The amount of a nutrient below which almost all healthy people can be expected, over time to experience deficiency symptoms.

 Adequate Intake (AI): The average a mount of nutrient that appears sufficient to maintain a specified criterion; value used as a guide for nutrient intake when RDA cannot be determined.  Tolerable Upper Intake level: The maximum amount of nutrient that appear safe for most of healthy people and beyond which there is an increase risk of adverse health effects.

Nutrition Assessment:  Nutrition Assessment: A comprehensive approach to determine a person nutrition status using:  Historical information  Anthropometric data  Physical examination  Laboratory tests

Historical Information :  Historical Information : 1- Health History Health factor that affect intake 2- Socioeconomic history Personal, financial. 3- Drug history medication interaction 4- Diet history intake excess or deficient a- A 24- hour recall a- A 24- hour recall b- Food record b- Food record c- Food frequency c- Food frequency -

 2. Anthropometric Data or Measurements:  Height – weight  over-nutrition, under nutrition  Head circumference Brain growth  Fat fold Subcutaneous and total body fat  waist circumference body fat distribution.

Body Mass Index BMI:  Body Mass Index BMI: AN index of a person weight in relation to height BMI = weight (kg) / height (m). BMI < 18.5= underweight. BMI 18.5 to 24.9 = normal. BMI 25 to 29.9 = overweight BMI > = 30 obese

Obesity and Maintenance  Increasing numbers of Americans are obese  Obesity-related conditions: –Type 2 diabetes Breast cancer –Heart disease Colon cancer –Hypertension Gout –Gallstones Osteoarthritis  To maintain weight … –Caloric input must equal caloric use  Calories burned depends upon –Activity level –Age –Height and build

 3 – Physical Examination: It looks for the clue to poor nutrition status, by inspecting hair, eyes, skin, tongue and others.  4 – Laboratory tests: Help to determine what is happening to the body internally, by analyzing the blood and urine samples, which contain nutrients, enzymes and metabolites that reflect nutrition status. Glucose, cholesterol, iron

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