1. Week 4

2. WHAT IS NUTRITION ASSESSMENT?
 The first step before planning and evaluating the
nutritional care of individuals or groups
 Determined on the basis of multiple kinds of
information
 A systematic method for obtaining, verifying &
interpreting information

3. Individual
Nutrition Assessment
Biochemistry
Energy
Anthropometry (Laboratory Clinical Dietary
Requirements
analysis)
Population
Assessment & Monitoring
Birth Monitoring
Food Household Mortality &
Food Anthropom wt, infant &
Supply & Dietary Morbidity
Prices etric Data feeding & Surveillanc
Data Surveys Data
mortality e System

4. ASSESSMENT OF INDIVIDUALS

5. ANTHROPOMETRY
 Study of physical dimensions of the body
 Standardised equipment & procedures essential
 Body size
 direct measurements
 height, weight, circumferences
 derived values
 Body shape
 Waist hip ratio, body weight distribution
 Body composition
 size of lean tissue and fat compartments

6. BODY MASS INDEX (BMI)
 One of the most commonly used measurements for
assessing nutritional status
 Ratio of weight to height
 Caution – BMI not ideal for determining health risk
as it does not reflect amount of muscle compared to
fat

7. CLASSIFICATION OF OBESITY IN CAUCASIAN ADULTS
Classification # BMI (kg/m2) IBW % * Risk of Chronic
Disease
Underweight <18.5 >10% below* Low (but other
risks)
Normal range 18.5-24.9 desirable Average
Overweight >25
pre-obese 25.0-29.9 (10-19% above*) Increased
obese class I 30.0-34.9 (>20% above*) Moderate
obese class II 35.0-39.9 Severe
obese class III >40 Very severe
# WHO 2000, AIHW (2004)
* Ideal body wt (IBW) or desirable wt for ht (US Metropolitan Life Insurance data)
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8. OBESITY CLASSIFICATION - OTHER ETHNIC GPS
BMI classification in kg/m2
Asian Pacific Is.
<18.5 <19.9 Underweight
18.5-23.9 20.0 - 26.9 Normal
weight
24.0-26.0 27.0-32.9 Overweight
27.0-39.0 33.0-39.9 Obesity
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9. ANTHROPOMETRY - CIRCUMFERENCES
1. Waist circumference (AIHW, 2005) > 18 y
 >94 cm (M) >80 cm (F) – abdominal
overweight
 >102 cm (M) >88 cm (F) – abdominal
obesity
2. Waist: hip ratio
 visceral fat around organs vs.
subcutaneous fat on hips
 optimal WHR is < 1 (M) or < 0.8 (F)
 varies with: genes, age, ethnicity, sex
 increased by 'stress', smoking, alcohol
 decreased by physical activity
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10. BIOCHEMISTRY
 Blood tests
 Readily obtained (so often used)
 Vary little (homeostatic control)
 Should be used in conjunction with nutrient and
supplementation history
 Tissue testing
 May include hair & nails for information about trace
elements
 Other tissues only acceptable under exceptional
circumstances (invasive)
 Urine testing
 Varies between nutrients and influenced by variety
of factors (including volume of urine)
 Multiple samples required
 Functional tests
 Ability to perform specific functions (e.g. muscle
response, immunological response)

11. BIOCHEMISTRY
 Advantages:
 Provide the earliest indications
of some nutrient deficiencies &
excesses
 Relatively accurate & unbiased
(although not perfect)
 Can provide evidence for a
nutritional diagnosis made on
the basis of signs & symptoms
 Can be used to assess the
effect of some nutritional
therapy

12. CLINICAL
 Information obtained includes:
 Socio-demographic details (age, gender, occupation)
 Medical history (including family history)
 Medications
 Physical functioning/activity
 To help identify patients at risk of nutritional
deficiency, excess or requiring specialised nutrition
therapy
 Signs & symptoms important

13. WHAT GROUPS MIGHT BE AT RISK OF
NUTRITIONAL DEFICIENCY?

14. DIETARY INTAKE
 Usual intake more informative than one day snapshot
 Methods of measuring dietary intake include
 Diet History
 24hr recall
 Food frequency questionnaire
 Food diaries
 Duplicate meals
 Covered in week 3 lecture (last week)
 Used to investigate quality of diet (core-foods) and energy
intake

15. ESTIMATING ENERGY - UNITS OF ENERGY
 Unit of energy = the Calorie OR the Joule
 Calorie is older unit of measurement
 One calorie = the heat energy required to:
 the temperature of 1g of H2O by 1 C
 in Australia, we use kilojoules (kJ)
1 calorie = 4.18 kilojoules
http://www.youtube.com/watch?v=AA1mBek0gsQ

16. WHERE DOES ENERGY COME FROM?
 Macronutrients in food
 Carbohydrates (found in
breads, cereals, fruits, vegetables, dairy and snack
foods)
 Protein (meat, eggs and dairy)
 Fat (meat, full-cream dairy, snack foods)
 Alcohol
 Each macronutrient provides a different amount
of energy per gram (the value of energy
provided is termed the ‘Atwater factor’)

17. ENERGY FROM MACRONUTRIENTS
Carbohydrates Protein
16 kJ/gram 17 kJ/gram
Fats Alcohol
37 kJ/gram 29 kJ/gram

18. WHAT IS ENERGY DENSITY
 To compare products we can calculate energy
density
 Energy density = the amount of energy per
gram of food
 Foods that have higher fat contents tend to
have higher energy density (e.g. take-away/
snack foods, fatty meats, fats & oils)
 Foods that are low in fat but have a high water
content have lower energy densities (there are
no kJ in water) (e.g. fruits and vegetables)

20. ENERGY DENSITY OF COMMON FOODS
Food Energy (kJ/g) Why?
pure fat e.g. oil 37 100% fat
butter, margarine 30 83% fat
chocolate 23
cheese 17 50% fat
bread 10 50% H2O
steak 9 > 50% H2O
soft drink 2 mainly H2O
celery 0.2 >90% H2O

21. ENERGY EXPENDITURE
 Basal Metabolic Rate (BMR)
 Min amount of energy required to maintain vital functions
 60-70% of total energy exp.
 dependent on
 body size
 body composition
 Gender
 Age
 other factors
 BMR lowest when resting
 Increases steeply as energy is used by muscles (i.e. during
exercise)

22. ESTIMATING ENERGY REQUIREMENTS
 Estimating BMR
 Prediction equations used
 Based on:
 age
 sex
 height
 Weight
 Commonly used in Australia are the Schofield equations
although there are many others

23. SCHOFIELD EQUATIONS
Males 10-18 (0.074 x wt) + 2.754
18-30 (0.063 x wt) + 2.896
30-60 (0.048 x wt) + 3.653
Over 60 (0.049 x wt) + 2.459
Females 10-18 (0.056 x wt) + 2.898
18-30 (0.062 x wt) + 2.036
30-60 (0.034 x wt) + 3.538
Over 60 (0.038 x wt) + 2.755
Important – These are estimations only. There is considerable
variation between individuals & even within individuals over time

24. ENERGY EXPENDITURE
 Calculating total energy expenditure
 Need to take into account minimum amount required (BMR) and
multiply by a factor to take daily activities and exercise into
account
 BMR estimated  multiply by activity factor
 Range of activity factors (resting  very heavy activity)
Resting Very heavy
Activity factor continuum activity
1.2
6 - 12
 TEE = BMR x av. activity factor across the 24-hr day

25. SCHOFIELD ACTIVITY FACTORS
Activity Level Males Females
Bed rest 1.2 1.2
Very sedentary 1.3 1.3
Sedentary/Maintenance 1.4 1.4
Light 1.5 1.5
Light/Moderate 1.7 1.6
Moderate 1.8 1.7
Heavy 2.1 1.8
Very heavy 2.3 2.0

26. ENERGY BALANCE

29. INTEGRATING INFORMATION ON
NUTRITIONAL STATUS
Nutrition Assessment involves integrating
information from a number of different sources to
define the specific problem & also how it might be
addressed

31. FOOD SUPPLY DATA
 Provide information on:
 Long-term trends in the availability of the major commodity groups
(grain, dairy, meat, F & V)
 The types of nutritional problems that are likely in different
countries
 e.g. where energy supply available is:
 ≥ 12000kJ/person/day  obesity & heart disease are common
 < 8000kJ/person/day  under-nutrition is likely
 The types of foods that supply energy

32. MORTALITY & MORBIDITY DATA
 Provide information on:
 diseases & conditions that are reported as causes of
death/hospital admissions
 possibly on chronic conditions such as cancer &
diabetes
 Reflect:
 the major social & health problems of the community
 And can be used as:
 clues to the most likely causes of mortality &
morbidity
 measures of the prevalence of specific nutrition
related conditions

33. MORTALITY & MORBIDITY DATA
 Only provide information on:
 Indirect measures of the kinds of nutritional
problems most likely to be encountered in a
population
 Multi-factorial aetiology of conditions in
developed countries
 Current burden of disease statistics available
from the AIHW
Disability adjusted life years (DALYs) are the years of life lost
due to premature mortality & disability & measure the number
of healthy years of life lost as a consequence of death or
newly diagnosed disease or injury in the population.

34. ANTHROPOMETRIC DATA
 Weight & height are used in population studies as they:
 provide an overall measure of nutritional status
 are non-invasive
 are quick to carry out
 use minimal (& cheap) equipment
 Provide information on:
 the growth of children
 the prevalence of obesity or underweight

35. DATA FOR CHILDREN
 Infant birth weight
 Provides information on:
 maternal health & nutritional status
 risk of infant mortality
 Is influenced by:
 maternal body size, infection, smoking, alcohol consumption, maternal
nutrition during pregnancy
Also
affects
 Infant mortality data
 % related to prevalence of low birth weight (populations with
high rates of low birth weight usually have high rates of infant
mortality) e.g. Indigenous Australians

36. INFANT FEEDING PRACTICES
 Inappropriate infant feeding practices influences growth &
development esp. in the 1st 4 to 6 months
 Decrease in breastfeeding at 3 months since 1945 (21% 1971,
above 50% since 1985)
 Breastfeeding or correctly prepared infant formula  infant
morbidity & mortality

37. MONITORING & SURVEILLANCE SYSTEM
 A National Food & Nutrition Monitoring & Surveillance System
needs to collect data on:
 Food supply & expenditure
 Mortality & morbidity
 Weight & height
 Plus extra information on
Nutritional issues of particular
concern via specific nutrition
surveys (see week 3 lecture)

38. MONITORING & SURVEILLANCE SYSTEM DATA
NEEDS TO
 be relevant to the major nutritional problems
encountered
 be available to decision-makers within a
reasonable timeframe
 be available on a regular basis
 be collected by standard methods to enable
trends over time to be established
 be presented appropriately
 contain information relevant for changes to be
made