2.a Dietary assessment Flashcards
What is the EAR?
(Estimated Average Requirement) = intake at which the risk of inadequacy is 50%
What is the RDA?
(Recommended Daily Allowance) = intake at which risk of inadequacy is 2-3%
What is the AI?
AI (Adequate Intake) = based on estimate of nutrient intake of healthy people
What is the UL?
UL (tolerable Upper intake Level) = Intake above UL is risk of adverse effects
Comparing individual intake with its requirements: how to do this?
EAR = best estimate of individuals requirement.
Approach:
Compare mean obs intake w/ median requirements
Mean obs intake>median: likely that the intake is adequate
- Obs intake < EAR: improvement is very likely necessary because probability is 50% or less
- Take other information into account e.g. health status
How is the EAR used for a group vs individual?
EAR individual: to examine the possibility of inadequacy
EAR group: to estimate the prevalence of inadequate intakes within a group
How is the RDA used for a group vs individual?
Individual: usual intake at or above this level has a low probability of inadequacy
Group: DO NOT USE
How is the AI used for a group vs individual?
Individual: usual intake at or above this level has a low probability of inadequacy
Group: Mean usual intake at or above this level implies a low prevalence of inadequate intakes
How is the UL used for a group vs individual?
Individual: intake above this level places an individual at risk of adverse effects from excessive nutrient intake
Group: Estimate the percentage of the population at risk of adverse effects from excessive nutrient intake
What are attention points for dietary assessment methods?
-Reference period
-Portion size requirements
-Food composition table
What are aspects of self-reporting?
- Food pattern, single foods
- Subjective
- Direct
- Quality hard to measure
- Time-consuming for participant and researcher
What are aspects of biomarkers?
- Nutrients
- Objective
- Usually indirect
- Easy quality control
- May be time-effective
- Invasive or burdensome for participant
Name 7 examples of dietary assessment methods
- 24-h recall
- Food record
- Dietary history method
- FFQ
- FFQ: screeners
- Technology-based methods
- Sensor-based methods
What is the 24-h recall?
- Recall of past 24-hours
- Interview (telephone/face 2 face)
- Usually unannounced
Application 24-h recall?
- monitoring studies
- Comparison between cultures
Advantages/disadvantages 24-h recall?
Advantages
- Easy for the respondent; captures all foods & drinks
Disadvantages
- Time-consuming for researcher
- Single day does not capture day-to-day variation
- Response (recall) errors
What is a food record?
- Record all foods and drinks for one or more days. Gather info about time, amount, brand names
Application food record?
Application
- Experiments, small studies, comparison between cultures
- Awareness of intake (could be the intervention!)
Adv/disadv food record?
Advantages
- Provides insight in timing, captures all foods & drinks
- Valid if done well
Disadvantages
- Time-consuming for participant and researcher
- Writing everything down change intake
What is the dietary history method?
- Habitual intake (in contrast to 24-h recall)
- Interview (telephone/face to face)
Application of dietary history method?
- Several, both for research or dietary advice
- Comparison between cultures
Advantages/disadv DHM?
Advantages
- Easy for participant
Disadvantages
- Experience interviewers needed
- Socially desirable answers likely; recall problems
What is a FFQ?
- Frequency of habitual consumption
- For estimating few nutrients or comprehensive list
Application FFQ?
- Large epidemiological trials
- To classify subgroups according to their intake
Adv/disadv FFQ?
Advantage
- Easy to use and analyse
Disadvantages
- Culturally-based
- No information on single foods
- not suitable for people with deviating diets
- Can take a long time to fill out; Recall problems
What are FFQ: screeners?
- Short questionnaires tailored for qualitative assessment of diet
- Fruits and vegetables, dietary patterns
Application of FFQ: screeners?
Needed when very limited time for questions on diet
Adv/disadv screeners?
Useful in situations that do not require assessment of total diet
Estimates of intake are not as accurate as those form more detailed methods
What do technology-based methods do?
- foods are ‘recognized’ by technology
- often rest on self-report, e.g sending pictures of food to app, scanning barcodes
Application of tech based meth?
- usually instead of 24-h recall or food record
- may appeal to certain target groups
adv/disadv tech based meth
Advantages
- may be less subjective and more ‘fun’ than recall and records
Disadvantages
- validity may be an issue
What do sensor-based tech do?
- Wear sensors that automatically record corporal movements related to eating activities
- sensors could register timing; bite size, etc
Application sensor-based tech?
Application
- short-term food intake, eating habits
Adv/disadv sensor-based tech?
Advantage
- memory-independent
Disadvantages
- rely on proper use of wearable
