Principles of Nutrition and Nutritional Assessment

2 Objectives of lecture By the end of this lecture you will be able to: Evaluate a diet using the food guide pyramid. Describe how nutrition influences growth and development throughout the life cycle. Discuss the components of nutritional assessment.

3 Introduction Knowledge of nutrients and the basic principles of nutrition is important in the role of patient teaching for disease prevention and health promotion. The basic food groups and their placement on a pyramid serve as a guide to basic, healthy nutrition.

4 K ey Principles of Nutrition(6 points)  Nutrients, including carbohydrates, fats, proteins, vitamins, and minerals, have specific functions within the body. They work together to provide energy, regulate metabolic processes, and synthesize tissues.

5 Cont…  Nutrition influences all body systems favorably and unfavorably. Examples of unfavorable effects include the link between cholesterol and heart disease or salt intake and high blood pressure. Favorable effects are many, such as the association of fiber intake with improved GI function and the role of folic acid in preventing neural tube defects.

6 Con….  Nutritional needs vary in response to metabolic changes, age, sex, growth periods, stress (trauma, disease, pregnancy, lactation), and physical condition.  Nutritional supplements may be needed depending on disease states, dietary intake, and other factors.

7 Con…  The types of foods eaten and eating patterns are developed during a lifetime and are determined by psychosocial, cultural, religious, and economic influences.  The nurse works with the dietitian or nutritionist to promote optimum nutrition for each patient.

8 Basic Food Groups and Food Pyramid Developed in 1958, the four basic food groups are grains, vegetables and fruits, meat, and milk. A fifth group is considered when looking at fat in the diet. A well-balanced diet consists of foods from each group. Additional information can be obtained from

9 Food Guide Pyramid

10 Key recommendations for the general population ( 8 points ) ▪Choose a variety of foods and beverages within and among the basic food groups. ▪Maintain body weight in a healthy range, balancing calories taken in with calories expended. ▪To reduce the risk of chronic disease in adulthood, engage in at least 30 minutes of moderate-intensity physical activity (above usual activity) most days of the week.

11 Con…. ▪To help manage body weight, engage in approximately 60 minutes of moderate- to vigorous-intensity activity on most days of the week while not exceeding calorie requirements. ▪Consume sufficient amount of fruits and vegetables.

12 Con…. ▪Consume three or more ounce-equivalents of whole grain products per day. ▪Consume 3 cups of fat-free or low-fat milk or equivalent product per day. ▪Consume less than 2,300 mg sodium per day. Nurses play an important role in guiding patients to make healthy choices about nutrition.

13 NUTRITIONAL ASSESSMENT There are many methods to assess the type and amount of food consumed, including a 24-hour recall of foods eaten, a food diary kept by the patient for several days, and a food frequency questionnaire that reflects food intake patterns. In addition to these specific tools, the following information is useful to determine nutritional patterns and status.

14 a. Key History Points(8 points) 1.General background information e.g. name, age, sex, family composition, socioeconomic status, occupation. 2.General health status and any chronic conditions, including diabetes and associated dietary restrictions. 3.Cultural and religious factors influencing dietary patterns. 4.Family history of diseases, including diabetes and obesity. 5.Current medications, over-the-counter products, and herbal supplements.

15 Con… 6. Food habits. ▪Typical daily intake, including meal frequency, meal timing, meal location. ▪Snacking patterns. ▪Food intolerance or dislikes. ▪Nutritional supplements, including vitamins, minerals, fortified beverages and foods. ▪Alcohol consumption. ▪Use of specific diets or dietary restrictions.

16 Con… 7. Food purchase and preparation. ▪Who purchases and prepares food and where food is purchased. ▪Facilities for food storage and preparation. ▪Factors influencing the types of food purchased.

17 Con… 8. Nutritionally related problems. ▪General well-being, energy level. ▪Weight change during the past 6 months. ▪Difficulty chewing or swallowing, use of dentures. ▪Change in sense of taste or smell. ▪Eructation, flatulence, nausea, vomiting, diarrhea, constipation, or abdominal pain or swelling in relation to food intake. ▪Bowel habits.

18 b. Physical Examination and Anthropometrics 1. Perform a systematic physical examination, observing for a wide variety of physical findings associated with nutritional status. ▪L▪Listlessness, apathy. ▪P▪Poor muscle tone. ▪D▪Dull, brittle hair; hair may be thin or sparse, easily plucked. ▪R▪Rough, dry, and scaly skin or dermatitis. ▪C▪Cheilosis (fissures at angles of mouth). ▪S▪Stomatitis (inflammation of mouth).

19 Con… ▪I▪Inflammation and easy bleeding of gums. ▪G▪Glossitis (inflammation of tongue). ▪D▪Dental caries and poor dentition. ▪S▪Spoon-shaped, brittle, ridged nails. ▪S▪Skeletal deformities such as bowlegs.

20 Con…. 2. Perform anthropometry as indicated. (Anthropometry comes from the word anthropology and is the science that studies the size, weight, and proportions of the human body to determine body fat mass, lean mass, and nutritional status.)

21 Con… Types of anthropometric measurements include height and weight, skin-fold thickness, and circumferential tests to assess nutritional status.

22 2-1: height and weight Height and weight are determined on patient admission and are later used as a baseline for comparisons in nutritional status. ▪Weight should be measured using a consistent and reliable scale and at a consistent time. ▪Unintended weight loss of more than 10% of body weight during 6 months is considered clinically significant and may be associated with physiologic abnormalities and increased morbidity and mortality. ▪Calculation of BMI.

23 2-2: Skin-fold thickness Skin-fold thickness provides an estimate of body fat based on the amount of fat in subcutaneous tissue using: a) Triceps skin-fold thickness b) Subscapular skin-fold thickness

24 2-3:Circumferential tests Circumferential tests provide information on the amount of skeletal muscle and adipose tissue. Mid-upper arm circumference an indirect estimate of the body's muscle mass.

25 c. Diagnostic Tests(5 points) 1. Serum albumin is a protein made by the liver, albumin is responsible for maintaining blood volume and serum electrolyte balance. A decrease in nutritional status may result in a drop in albumin synthesis. However, in chronic malnutrition, serum albumin levels are typically normal or high.

26 Con… 2. Hemoglobin is made by the liver. 3. Serum transferrin is another transport protein made by the liver; responsible for binding iron to plasma and transporting it to the bone marrow. Reduced levels are found in catabolic states and some chronic diseases.

27 Con ….. 4. Twenty-four hour urine creatinine is an increase in this measure indicates increased tissue breakdown. 5. Twenty-four hour urine urea nitrogen or total urinary nitrogen is this test can be used to determine nitrogen balance.

28 Reference Authors/Editors: Nettina, Sandra M.; Mills, Elizabeth Jacqueline Title: Lippincott Manual of Nursing Practice, 8th Edition Copyright آ©2006 Lippincott Williams & Wilkins > Table of Contents > Part Two - Medical- Surgical Nursing > Unit V - Gastrointestinal and Nutritional Health > Chapter 20 - Nutritional Problems