WEEK9 Evaluation of nutrient intake data Flashcards
EAR
Estimated Average Requirement
The average requirement of a group for a particular nutrient or energy (approx 50% will require more and 50% less)
RNI
Reference Nutrient Intake
EAR+2SD
The amount of a nutrient that is enough to ensure that the needs of nearly all the group are met
Exceeds requirement for most people
Habitual habits above the RNI are almost certainly adequate
LRNI
Lower Reference Nutrient Intake
EAR-2SD
The amount of a nutrient enough for only a small number of people with low requirements
Habitual intakes below the LRNI will almost certainly be inadequate
Safe Intakes
A level of intake where there is no risk of deficiency
Below a level where there is a risk of undesirable effects.
SI set for nutrients that have insufficient data to set DRVs e.g biotin, pantothenic acid, vitamin E, vitamin K, manganese, molybdenum and chromium
Safe Upper Intake Levels / Tolerable Upper Intake Levels (TUIL)
an intake level that can be consumed daily over a lifetime without any significant risk to health
EER
Estimated Energy Requirements
The average energy intake required to maintain current body weight and activity level (and to allow for growth and milk production, where relevant) in healthy normal weight individuals of a specified age, gender, height, weight and physical activity level.
Derived based on doubly labelled water measurements of energy expenditure
No available adjustments for those with overweight/obesity, Total Energy Expenditure (TEE) is calculated to maintain - not consistent with long term health.
Comparisons of individuals intakes with RNIs
If an individual’s mean intake of a nutrient is >RNI it is LIKELY that intake is adequate
falls below rni = not necessarily inadequate for their individual needs
falls below lrni = likely inadequate
Comparison of individual’s intakes with EARs
Difficult - actual nutrient requirements for an individual not always known
Standard deviation or Z score
provides a measure of an individual’s nutrient intake relative to the distribution of the corresponding nutrient intakes of the group
This method does not evaluate nutrient intakes relative to DRV’s
Useful in longitudinal studies for monitoring changes in the nutrient intakes of individuals relative to the group
An estimate of whether an individual meets their requirement.
Z Score Equation
individual’s nutrient intake value – mean value for the group / SD value for that nutrient for the group
Is RNI appropriate for measuring group intake?
NO
The RNI by definition, is an intake level which exceeds the requirements of 97-98% of all individuals
So the RNI would OVERESTIMATE the proportion of the group at risk of inadequacy and should therefore not be used to assess nutrient intakes of GROUP’s
The Probability Approach for EAR
Attempts to assess more reliably the risk of nutrient inadequacy
individual - estimates the relative probability that the nutrient intake does not meet actual requirements.
BUT doesn’t identify with certainty which individuals are at risk
group - predicts the number of individuals within a group with nutrient intakes below their own requirements i.e at risk
What info is required for probability approach
- The EAR for each nutrient for the particular age/sex group
- The distribution of requirements for each nutrient among similar individuals - for most nutrients this is not known and is presumed to be normally distributed
- Reliable data on the distribution of USUAL intakes for the group being assessed
Probability approach class system
see ppt
What is the Ear Cut Point Method
Short cut to this probability approach
The number of individuals in a group with USUAL intakes below the EAR are counted
