2. Food and
Food Food Physical Nutritional
Supply purchasing & Activity Status
acquisition Behaviours
4. Food intake data
Prospective (current)
•Food diaries
• Household measures or weighed
•Chemical analysis
•Duplicate meals
Retrospective (past)
• Actual
• 24-hour recall
• Food Frequency Questionnaires
• Usual
• Dietary Histories
5. Food Diaries
Using household measures
Set time period for recording (minimum 3 days)
Record all food consumed & drink over there days in
diary
Include a non-working day
Using weights
Similar recording to above but use a set procedure for
weighing using scales & measuring utensils
What are the advantages?
What are the limitations?
Musicians Daily Diet
Credit: PETER MENZEL/SCIENCE PHOTO LIBRARY
6. Page from a food diary example
http://www.srl.cam.ac.uk/epic/images/7dfd.jpg
7. Chemical analysis (duplicate
meals)
Collection of an identical
meal/food from client for
analysis
useful for analysing food
composition
Limitations
expensive & time consuming
impractical outside confined
setting
8. 24-hour recall (current
intake)
Ask individual to remember what food &
drinks they have consumed in previous
24 hours or day
usually performed by trained interviewer
What are the advantages?
What are the limitations?
Tea farmers daily diet, Kenya
10. Food frequency questionnaire
(current intake)
Qualitative & semi-quantitative survey of:
how often foods are eaten +/- how much
usually self administered, can be interview
general or specific FFQ
What are the advantages?
What are the limitations?
11. Diet history
Assess typical intake
Bakers Daily Diet, Iran
Original Adaptation - 3 components
1. a usual 24-hour recall
usual takes away atypical errors
food amounts enhanced by using food models
2. a checklist
3. a short (3 days) diary
12. Construction Workers
Diet History Daily Diet, USA
An investigation of habitual intake over a
specified period of time – usually 1 mo to 1 yr
24 hour recall + variations
Details on types (e.g. low fat), quantities, brands)
Indicates patterns of eating
Able to estimate energy, macro & micro nutrients
Able to estimate food groups
Can be targeted to particular nutrients e.g.
carbohydrate in diabetes
Administered by a trained health professional
14. Limitations of food intake data – diet history
honesty, memory & frankness of client
need highly skilled interviewer
expensive & time consuming
may underestimate intake
Most useful information for
assessment
15. Photographic dietary records
Relatively novel method of assessing intake.
Require the individual to photograph food before eating
(prospective method). Any food left over is also
photographed. A reference object (e.g. card, coin) is often
included in the photograph. Additional information to
indentify items (i.e. description) is often necessary.
Analysis of records can be either manual (by dietitian or
other trained person) or automatic using image analysis
software. Manual analysis should include the use of aids
to reduce portion size estimation error.
Stand-alone camera or mobile phone with camera
function can be used.
Megan Rollo, QUT PhD Student
16. Example: recording intake using
Nutricam
1. Mobile phone with Nutricam software.
2. Capturing an image of items for consumption.
“At home...
black coffee,
one sugar...
orange
juice…
cornflakes,
reduced fat
milk.”
4. Image and voice file sent to website for analysis.
3. Describing items in image (recording voice file).
Megan Rollo, QUT PhD Student
18. How do we investigate food
intakes over time?
Reliable trends in food intake over time can only be
established from data collected using the same
survey design & food intake methodology.
Can achieve this via the aid of national dietary
surveys (of intakes)– to provide information on
average intake of population
1995 National Nutrition National Health
Survey Survey
19. 2007 Australian National Children's
Nutrition & Physical Activity Survey
More than 4000 children across Australia
Collected data on food and nutrient
intake, physical activity levels and
physical measurements (height, weight
and waist measurements) of children
aged 2-16 years.
24-hr recall + follow-up survey
Purpose: “to provide the information
needed for public and private sectors to
work together to develop targeted
strategies to address a range of health
concerns in children”
http://www.health.gov.au/internet/main/publis
hing.nsf/Content/health-pubhlth-strateg-
food-monitoring.htm
20. 2011/13 Australian Health Survey
Australian Bureau of Statistics and Department
of Ageing
Expands upon previous surveys
Involves ~ 50,000 adults and children across
Australia.
Will be conducted in homes
Topics include demographics, risk
factors, health status, medications, chronic
diseases, use of health services, and nutrition
and physical activity habits.
Voluntary blood and urine sample
21. Purpose of Dietary
Surveys
Provide information on:
Likely impact of changes to food regulation
Levels of additives & contaminants in the food supply
Proportion of population complying with recommendations
Need for targeted population level interventions
Need for, & impact of, fortification of foods
Australian Health Survey 2011/13 Objectives
assess the level and distribution of the health of populations
measure the level, distribution and influence of health
determinants
quantify the inputs to the health system
monitor and appraise health interventions
increase knowledge through research and statistics
evaluate the performance of the health system
understand the interrelationships of all the above.
22. References Cont
Commonwealth Scientific Industrial Research
Organisation (CSIRO ) Preventative Health National
Research Flagship, and the University of South Australia,
2007 Australian National Children’s Nutrition and
Physical Activity Survey Main Findings, Commonwealth
of Australia, Canberra.
Notes de l'éditeur
Last week we we discussed how we assess or monitor the food supply, using food balance sheets to assess food available for use and consumption, as well as food purchasing and acquisition data. This week we will investigate how we measure actual food intake and consumption.
So how do we measure the diets of individuals?Measuring food intake is one of the most difficult tasks undertaken by health professionals for several reasons. Food supply is extremely variedIndividuals eat widely varying amounts and combinations from day to dayVariations exist in recipes and nutrient content of different versions of the same foodTask of recording foods in detail is time consuming and requires a lot of co-operation from respondents
There are two overarching categories under which dietary data collection methods fall, prospective and retrospective. Prospective methods investigate current intakes, so they essentially look at the ‘here and now’. These strategies include food diaries or journals, duplicate meals, and novel approaches such as photographic dietary records.Retrospective methods investigate previous, or past, dietary intakes. Retrospective diet methodologies may include 24-hour recalls (in which people are asked what they ate or drank in the last 24 hours), food frequency questionnaires, and ‘diet histories’ which may include a variety of data collection methods and aim to ascertain what people ‘usually’ eat.
Diet histories are most commonly used in clinical dietetic practice. There are multiple variations of the ‘diet history’. Undertaking a typical diet history traditionally involves a ‘usual’ 24-recall, in which participants reported on the previous days intake and whether this represents their typical diet, a checklist to jog the clients memory, and further validation through the inclusion of a 3 day food diary.
The national health survey is a 3 yearly survey of approximately 26,000 participants, and assesses a wide range of health conditions, as well as a small number of dietary intakes via short-answer questions. These include ‘how many servings of fruits or vegetables do you consume per day’ and ‘what type of milk do you usually consume’ which is used as a proxy measure for fat.The NNS 1995 was a more detailed investigation of diet undertaken among 13 858 Australians > 2 years of age who participated in the NHSConducted using 24hr recalls in the homeThis method allowed a large number of people to be included The decision was made to use this method to allow comparison with other studies (1983 & 1986 NNS(Most recent National Nutrition Survey to date