Dietary assessment Flashcards
What is the importance of national diet survey
important to assess dietary habits and nutritional status
What is the difference between retrospective and prospective?
retrospective = food already consumed
- FFQ
prospective = while food is consumed
- Diary
How to address under-reporting?
use objective assessment methods (biomarker)
- design instruments to reduce bias
What is the accuracy of 24-hr recall?
70-80%
In interviewing, what determines quality in the data?
the success of probing
What is the multipass method and its purpose and steps?
To reduce underreporting
- Quick list
- Forgotten foods
- Time and occasion
- Detail cycle
- Final probe
What is FETA?
FFQ System used for EPIC Norfolk
- 130 items in it
Why use biomarkers?
- objective
- quicker
- more details
however - collection of specimen done, with fewer details obtained
- requires sample analysis
What type of biomarkers are there?
- Recovery - allows determination of intake
- Predictive
- reference measurement - Concentration - biomarker allows ranking of intake
Give some actual example of biomarkers for dietary assessment and its use:
- Urinary nitrogen = total urine intake
- Potassium
- Doubly-labeled water
What are examples of biomarkers based on properties possessed:
- pH
2. Isotope ratio = d13C/d13N
What other examples of biomarkers are based on compounds
- Food components (protein, sugar, fat, micronutrients, phytochemicals)
- Contaminants/by-products (metabolites)
- heavy metals
- preservatives
- processing by-products
Give examples of phytochemicals
- Alkaloids
- Alkylresorcinols
- Carotenoids
- Isothiocyanate
What are some phenolic compounds used as biomarkers?
- phenolic acids
- flavonoids
What is a respiratory chamber and its function?
- measure oxygen and CO2 exchange
- estimate EE based on oxygen consumption and CO2 production
What are the assumptions of doubly-labelled water technique?
- oxygen turnover in body is dominated by water flow and inspired oxygen and expired carbon dioxide
- Hydrogen turnover in body is dominated by water flow only
- Differences between oxygen and hydrogen turnover measure oxygen consumption
On a timescale, which 5 dietary assessments take months to years to analyse?
- teeth
- bone
- nails
- hair
- RBC
On a timescale, which 2 dietary assessments take months to analyse?
FFQs
Adipose tissue
(maybe hair and bones)
On a timescale, which 3 dietary assessments take hours to analyse?
Urine
plasma/serum
(maybe FFQs)
On a timescale, which 5 dietary assessments can sort-of obtain quite immediate results?
- 7DD (7-day diary)
- Saliva
- Sweat
What are advanced methods of dietary assessments?
- web-based questionaires
2. TADA
