DRIs Flashcards
DRIs replaced
DRIs began
Original US RDAs established in 1941 and the Canadian RNIs since 1938 (Recommended Nutrient Intakes)
Began in 1997 with a joint collab between Health and Welfare Canada, USDA, NIH, US Academy of Science (FNB of IOM)
The last reviewed before the 1997 DRI recommendation standards
RNI (formerly RDNI pre-1983), Canadian, 1990
FAO/WHO/UNU Safe level of Intake 1985
US Recommended Dietary Allowance (RDA) 1985, 1989, 1995
Overall structure of DRI committee
Standing Committee for the Scientific Evaluation of DRI: oversees the 5 year process
Nutrient Expert Panels develop, in conjunction with two subcommittees (use of DRI and upper reference levels), the series of DRI Reports, based on a review of the scientific literature.
7 DRI sub-committees
7 sub-committees:
1) Ca, vit D, P, Mg, F
2) Folate, B12, B vitamins, choline
3) Antioxidants and related nutrients
4) Trace elements
5) Electrolytes
6) Energy and Macronutrients
7) Other food components (probiotics, carotenoids, tannins,etc things that improve lifespan)
The 4 DRIs
Overall goals of DRIs
EAR = estimated average requirements
- covers 50% of population’s needs
RDA = recommended dietary allowance
AI = adequate intake
- alternative reference when EAR/RDA are not available
- for nutrients without clear biomarkers of sufficiency
UL = tolerable upper limit
Overall current goals: look at RDAs, make recommendations based deficiency and chronic disease prevention, establish UL based on common intake, include non-essential food components for chronic disease prevention
RDA Overview
Distribution
How it is determined
EAR + 2 SD or 97-98% of population of a specific life stage and gender
- Meant to meet the needs of most healthy individuals NOT groups
- the SD account for variability in nutrient needs
Refer to distribution of av. daily intake over time
- RDA exceeds the requirements of nearly all reference group over time
Determined through experimentation in a healthy population and based on estimation of minimal requirement to achieve some outcome/biomarker
RDA accounts for
1) Coefficient of variability within a population (individual variability or how stretched the bell curve is)
2) Bioavailability
3) Sex and age differences
4) Physiological state (lactation, adolescence)
To set RDA take into account what kinds of data
Usual intake distribution, deficiency state studies, balance studies, animal studies, extrapolated data based on other age groups
Deficiency and balance studies show a quantitative relationship between intake below a certain level and deleterious changes in biochemical & physiological responses.
EAR definition
Usually intake level to meet the requirement of half the healthy individuals in a life stage and gender group
- for assessing prevalence of inadequacy for groups - based on intake distribution NOT average individual intakes
Foundation for setting RDA
