Module 2

• Malnutrition


  Any condition caused by excess (over-nutrition) or deficient (under-nutrition) food energy or nutrient intake
• Over-nutrition


  Excess energy or nutrients
• Conditions associated with excess energy

  • Obesity, diabetes, heart diseases, some cancers

  
• Symptoms of nutrient excess

  • Gastro-intestinal distress (vitamin C), skin yellowing (beta-carotene), hypertension (sodium)

  
• Under-nutrition


  Deficiency of energy or nutrients

  
• Conditions associated with energy deficiency

  • Muscle wasting, weight loss, infections, disease
• Symptoms of nutrient deficiency

  • Skin rash (flushed-looking skin) (niacin), Hair loss (protein), Confusion (vitamin K), Bleeding gums (vitamin C)
• Nutrient Deficiency takes time to develop

  
• Appropriate nutritional assessment tools can identify deficiencies at any of these stages and allow intervention to restore nutritional health

  
• Dietary Assessment


  Information and the interpretation of that information obtained from the ABCD's: Anthropometric measurements, Biochemical (laboratory measurement), Clinical, Dietary
• Anthropometric Methods


  • Detect moderate/severe malnutrition, Need to account for nutritional history

  
• Anthropometric Examples


  • Body mass, body mass index, waist circumference, waist-to-hip ratio, other body circumference measures

  
• Body Composition Examples


  • Skinfold thickness, hydrostatic weighing, air-displacement plethysmography, bioelectrical impedance, dual-energy x-ray absorptiometry
• Body Mass


  Terms weight and mass are used interchangeably, Commonly measured on a standard calibrated scale (kg)

  
• Problems associated with looking at mass alone: Does not account for body size (e.g., taller person, more mass)</b>

  
• Body Mass Index (BMI)


  A universally adopted classification system, Same for both sexes and all ages of adults, Only for use in adult populations (non-pregnant), BMI = mass (kg) / height (m2)

  
• BMI Categories


  • Underweight (<18.5 kg/m2), Normal weight (18.5-24.9 kg/m2), Overweight (25.0 – 29.9 kg/m2), Obese Class I (30.0 – 34.9 kg/m2), Obese Class II (35.0 – 39.9 kg/m2), Obese Class III (>40.0 kg/m2)
• Underweight


  15% or more below ideal BW, BMI < 18.5 kg/m2 (sometimes <20), Potential health problems: Respiratory conditions, Immune suppression, Nutrient deficiencies, Inadequate reserves to fight wasting disease, Osteoporosis, Reduced fertility, Menstrual irregularities, Risk of low birth weight babies

  
• Overweight / Obese


  Increased mortality from: Cardiovascular disease, Cerebrovascular disease, Type 2 diabetes, Cancer

  
• Nurse health study (n=115,000): women with BMI >29 had over 3x the risk of having fatal heart disease
• Definition of overweight is controversial; and there are some problems with BMI

  
• BMI does not apply to: infants, children, pregnant or lactating women, adults over 65 years, athletes, people with edema, massive tissue loss, very lean people
• BMI should be used with caution for adolescents (<18y), as they may not have reached full height

  
• Waist Circumference


  Estimates abdominal/visceral obesity, which has a stronger association with type 2 diabetes & CVD than BMI, Used in combination with BMI, provides a more robust index of overall obesity-related health risk than BMI alone

  
• Waist Circumference Cut-offs


  • Males: <102cm, Females: <90cm
• Waist-to-Hip Ratio (WHR)


  Compares circumference of waist to that of the hip and is used as an indicator of body fat distribution (i.e., apple or pear physique) or as a measure of general health, High WHR recognized as risk factor for disease
• Body Circumference Measures


  Track body morphology over time, Measured at standard anatomical sites around the body, typically with a tape measure
• Body Composition


  Relative amount of fat mass (essential and storage) vs. the amount of fat-free mass (bone, muscle, organs, water)

  
• Body Fat % Guidelines

  • Males: Too low (<3-5%), Normal (12-20%), Borderline (21-25%), Obese (>25%), Females: Too low (<8-12%), Normal (20-30%), Borderline (31-33%), Obese (>33%)

  
• DXA


  Gold standard of body composition assessment, Three-Compartment Model: Fat mass, Lean mass, Bone mass, Estimate of fat & lean soft tissue mass, Attenuation of x-rays is related to type of tissue, Provides regional measures
• DXA can also estimate bone mineral content and areal bone mineral density (aBMD)
• Nutrients related to poor bone health

  • Calcium, Phosphorus, Magnesium, Fluoride, Vitamin D, Vitamin K
• Biochemical Methods


  Biochemical tests on tissue or fluid samples (e.g., blood, urine) can detect levels of certain nutrients, Helps determine what is happening inside the body, Helps evaluate risk for nutrition-related chronic diseases
• The ideal tool for biochemical analysis should be objective, quantitative, and able to measure blood or urine (relatively non-invasive)
• Dietary assessment


  Information and the interpretation of that information obtained from the ABCD's: Anthropometric, Biochemical, Clinical, and Dietary sources
• ABCD's of dietary assessment

  • Anthropometric measurements
  • Biochemical (laboratory measurement)
  • Clinical
  • Dietary
• Biochemical methods


  • Objective
  • Quantitative
  • Able to measure blood or urine (relatively non-invasive)
• Biochemical methods


  Measures of nutrients in body fluids (blood or urine)
• Clinical methods


  Dietary needs depend on genetic background, life stage, and health status

  
• Clinical methods example


  • Diabetes study - medical history section of an online survey