KIN275: Introduction to Nutrition - Module 2 Study Notes

KIN275: Introduction to Nutrition - Module 2 Notes

Overview of Nutritional Assessments

  • Food and nutrition are indispensable human needs.

  • Nutrition plays a critical role in maintaining the health and well-being of individuals.

  • Nutritional requirements of healthy individuals depend on various factors such as:

    • Age

    • Sex

    • Activity levels

  • Key concept: Dietary Reference Intakes (DRIs) provide recommendations to help individuals meet their nutritional requirements.

  • Nutritional imbalances can lead to malnutrition, which can manifest as:

    • Undernutrition:

    • Energy deficiency

    • Micronutrient deficiency

    • Overnutrition:

    • Energy excess

    • Micronutrient excess

Examples of Nutritional Imbalance

Undernutrition

  • Conditions associated with energy deficiency include:

    • Muscle wasting

    • Weight loss

    • Increased infections

    • Disease susceptibility

  • Symptoms of nutrient deficiency can manifest in various forms, such as:

    • Skin rash (indicative of niacin deficiency)

    • Hair loss (related to protein deficiency)

    • Confusion (linked to vitamin K deficiency)

    • Bleeding gums (associated with vitamin C deficiency)

Overnutrition

  • Conditions linked to energy excess include:

    • Obesity

    • Diabetes

    • Heart diseases

    • Certain cancers

  • Symptoms of nutrient excess may include:

    • Gastrointestinal distress (from excess vitamin C)

    • Skin yellowing (from excess beta-carotene)

    • Hypertension (from excess sodium)

Malnutrition

  • Malnutrition can involve simultaneous undernutrition and overnutrition

  • Can be classified into:

    • Acute

    • Sub-acute

    • Chronic

  • May or may not be associated with underlying inflammation.

  • Nutritional screening is a quick method used to identify individuals at risk of malnutrition, such as using the Mini Nutritional Assessment (MNA).

    • Effective for identifying malnourished patients or individuals at risk.

    • Screening can be done in less than 5 minutes and does not require lab tests.

  • For comprehensive nutritional assessment:

    • Evaluates nutritional status of individuals already identified at risk.

    • Helps diagnose malnutrition and identify underlying pathologies, and assists in planning necessary interventions.

Factors Affecting Nutritional Status

  • Physiological factors:

    • Age

    • Sex

    • Growth (particularly in childhood and pregnancy)

    • Lactation

    • Physical activity levels

  • Pathological factors:

    • Genetics

    • Infections

    • Surgical history

    • Trauma

    • Malignancies

    • Use of medications

  • Psychosocial factors:

    • Socioeconomic status (SES)

    • Cultural norms

    • Religious beliefs

    • Eating disorders

    • Mental health issues

    • Unhealthy dietary trends

    • Alcohol and substance abuse

Learning Objectives for Module 2

  1. Discuss the ABCD's of nutritional assessment

  2. Discuss dietary analysis

The ABCD's of Nutritional Assessment

  • There is no single best test for evaluation. Instead, information should be collected systematically.

  • Team-based evaluations should be performed on the overall data collected:

    1. Anthropometric measures

    2. Biochemical laboratory measurements

    3. Clinical assessments (history and physical examination)

    4. Dietary assessments

Assessment Methods

  • Deficiency Types:

    • Primary deficiency caused by inadequate diet.

    • Secondary deficiency resulting from internal problems in the body.

  • Methods to assess changes include:

    • Diet history

    • Health history

    • Monitoring declining nutrient stores (subclinical) and assessing overt physical signs/symptoms through laboratory tests

    • Physical examinations and anthropometric measures.

Clinical History Considerations

  • Dietary needs vary based on:

    • Genetic background

    • Life stage

    • Health status

  • Example considerations for various life stages:

    • Pregnant women require more nutrients for fetal growth.

    • Infants have higher energy and protein needs relative to body mass compared to other life stages.

    • Older adults may experience changes in body composition and capacity to digest and absorb nutrients.

  • Important clinical factors include:

    • Pre-existing health conditions (e.g., arthritis affecting food acquisition and GI disorders affecting digestion)

    • Symptoms that may indicate underlying issues (e.g., fever, weight loss, eating habits, bowel habits, menstrual history)

Physical Examination Details

  • Assessments may include:

    • General condition

    • Vital signs

    • Height and body mass

    • Observations of eyes, oral cavity, skin, hair, nails, extremities, and odors

    • Functional assessments and systemic evaluations

Laboratory Tests

  • Laboratory tests validate clinical presentation results.

  • Common routine clinical tests include:

    • Serum electrolytes

    • Blood urea nitrogen (BUN)

    • Blood glucose levels

    • Lipid profiles

    • Complete blood count (CBC)

  • Biochemical Indicators:

    • Visceral proteins (e.g., albumin, prealbumin) should be interpreted cautiously due to influencing factors.

    • Micronutrient levels should be evaluated when deficiencies are suspected (e.g., B vitamins, Vitamins A, C, D, E, and various minerals).

Biochemical Methods and Data

  • Normal Ranges for Blood Cells:

    • Red blood cells:

    • Men: 4.5−6.5imes10124.5 - 6.5 imes 10^{12} /L

    • Women: 4.0−5.6imes10124.0 - 5.6 imes 10^{12} /L

    • White blood cells: 4.0−10.0imes1094.0 - 10.0 imes 10^{9} /L

    • Hematocrit, Hemoglobin, Ferritin, calcium, iodine, etc.

    • Obtaining values such as pH, total protein, albumin, cholesterol, etc., can indicate overall health conditions.

Anthropometric Measures

  • Includes:

    • Height, body mass, Body Mass Index (BMI)

    • Consider hydration and body composition aspects such as edema.

    • Circumferences (waist, hip, arm, thigh)

Body Mass Index (BMI)

  • A universal classification system used only for adults (non-pregnant):

  • Calculation:

    • BMI = mass (kg) / height (m²)

    • Example: 5’6”, 145 lb female calculation:

    • 145 lbs / 2.2 kg = 65.9 kg

    • 66” = 1.68 m (converted to cm)

    • BMI = rac65.9(1.68)2=23.5extkg/m2rac{65.9}{(1.68)^{2}} = 23.5 ext{ kg/m}^2

BMI Classification

  • Underweight: < 18.5

  • Normal weight: 18.5 - 24.9

  • Overweight: 25.0 - 29.9

  • Obese (Classes I, II, III):

    • Class I: 30.0 - 34.9

    • Class II: 35.0 - 39.9

    • Class III: > 40.0

Health Risks Associated with BMI Categories

  • Increased health risk associated with higher BMI values.

  • Mortality risk increases with both higher and lower BMI values.

Underweight

  • Represents 15% or more below ideal body mass with potential complications such as:

    • Respiratory conditions

    • Immune suppression

    • Nutrient deficiencies

    • Osteoporosis

    • Fertility issues

Overweight/Obese

  • Common knowledge correlates increased BMI with increased mortality from:

    • Cardiovascular diseases

    • Cerebrovascular diseases

    • Type 2 diabetes

    • Specific cancers

  • Example: Nurse Health Study indicates women with BMI > 29 had over 3x the risk of fatal heart disease.

Waist Circumference

  • Measures abdominal/visceral obesity, which is more closely linked to type 2 diabetes and cardiovascular diseases than BMI alone.

  • Recommendations:

    • Males: < 102 cm

    • Females: < 90 cm

  • Important for identifying health risks even if BMI indicates a normal weight.

Body Composition

  • Components:

    • Fat Mass vs. Fat-Free Mass (essential vs. storage)

  • Essential body fat:

    • Men: 3-5%

    • Women: 8-12%

  • Non-essential body fat is generally stored and does not contribute directly to physiology.

  • Various methods to measure body fat include:

    • Skinfold measures

    • Hyrodensitometry

    • Bioelectrical impedance

    • Dual-energy x-ray absorptiometry (DEXA)

Dietary Assessment

  • Involves the history of dietary habits, meal frequency, serving sizes, and food preferences.

  • Current nutrient intake can be assessed through:

    • 24-hour recalls

    • Food frequency questionnaires

    • Observational methods

    • Nutritional analysis software

24-Hour Food Recall

  • A common method for dietary assessment.

  • Involves detailed questioning to capture what an individual ate in the previous 24 hours.

  • Can include information on cooking methods, brands, etc.

Food Frequency Questionnaire

  • Estimates dietary patterns over a specified time frame through questions about frequency and amount of food consumption.

Use of Software for Dietary Analysis

  • Various online nutrient databases and software are utilized for assessment, including MyFitnessPal and Cronometer.

  • They allow comparison of nutrient intake to recommended amounts.

Challenges of Dietary Assessment

  • Errors can stem from multiple sources:

    • Data reliability

    • Food recording accuracy

    • Relying on memory

  • People may underreport or change their dietary intake when aware of being monitored.

Summary of Key Points

  • Nutritional assessments combine the ABCDs framework (Anthropometric, Biochemical, Clinical, Dietary) to evaluate nutritional status.

  • Effective dietary assessments help identify deficiencies or excesses, long-term risks related to diet.

  • Despite available tools, diagnosing nutritional deficiencies remains complex.