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Implementing food-based dietary guidelines for - United Nations ...

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S18<br />

intake of an essential nutrient that, on the basis of scientific<br />

knowledge, is judged by the Food and Nutrition<br />

Board to be adequate to meet the known nutrient needs<br />

of practically all healthy people. The RDA continues to<br />

be used as one of the nutrient intake values included<br />

in the US/Canadian DRIs. The RDA is <strong>based</strong> on a<br />

statistical distribution of individual requirements <strong>for</strong><br />

meeting a chosen criterion of adequacy <strong>for</strong> the target<br />

nutrient, such as calcium, vitamin A, or protein. Based<br />

on the statistical distribution of requirements, the RDA<br />

is set at a level of intake that meets the needs of 97%<br />

to 98% of healthy individuals in a particular age- and<br />

sex-specific group.<br />

EAR (estimated average requirement)<br />

Using the same statistical distributions <strong>for</strong> nutrient<br />

requirements, the EAR is the average or mean daily<br />

nutrient intake that meets the requirement of half the<br />

healthy individuals in a particular age- and sex-specific<br />

group.<br />

AI (adequate intake)<br />

The AI is defined as the observed or experimentally<br />

derived intake by a defined population group that<br />

appears to sustain health [3–7]. An AI is used when<br />

there are insufficient primary data to establish a statistical<br />

distribution of individual requirements and,<br />

there<strong>for</strong>e, an EAR and RDA. The AI is estimated in<br />

a number of different ways. For some nutrients, it is<br />

<strong>based</strong> on the observed mean intakes of groups with an<br />

apparent low prevalence of nutrient inadequacy. For<br />

example, an AI is used to represent the nutrient intake<br />

values <strong>for</strong> infants because they were derived from the<br />

nutrients supplied by human milk. The AI has also<br />

been derived from the results of experimental studies<br />

when data were thought to be inadequate to describe<br />

a statistical distribution of requirements <strong>for</strong> a specific<br />

function or criterion. Examples include calcium, vitamin<br />

D, fluoride, and sodium.<br />

AMDR (adequate macronutrient distribution range)<br />

The AMDR specifies the upper and lower boundaries<br />

<strong>for</strong> percentage of energy from macronutrients (i.e.,<br />

carbohydrate, fat, n-6 and n-3 polyunsaturated fatty<br />

acids, and protein) [6]. These boundaries are generally<br />

<strong>based</strong> on intakes associated with reducing the risk of<br />

chronic disease.<br />

UL (tolerable upper intake level)<br />

The UL is defined as the highest level of daily nutrient<br />

intake likely to pose no risk of adverse health effects <strong>for</strong><br />

nearly all individuals in the group (general population)<br />

[9]. The level is also estimated from a statistical analysis<br />

of the risk assessment associated with a range of high<br />

nutrient intakes. The term tolerable intake was chosen<br />

to avoid implying a possible beneficial effect [9].<br />

British terminology<br />

DRV (<strong>dietary</strong> reference value)<br />

Dietary reference values (DRVs) are nutrient-<strong>based</strong> <strong>dietary</strong><br />

standards recommended by the <strong>United</strong> Kingdom<br />

in 1991 [10, 11]. The DRVs apply to groups of healthy<br />

people and are not appropriate <strong>for</strong> those with disease<br />

or metabolic abnormalities. As <strong>for</strong> US/Canadian DRIs,<br />

the DRVs <strong>for</strong> a nutrient assume that requirements <strong>for</strong><br />

energy and all other nutrients are met when deriving<br />

a specific reference value. The British DRVs provide<br />

three values <strong>for</strong> most nutrients: the lower reference<br />

nutrient intake (LRNI), the estimated average requirement<br />

(EAR), and the reference nutrient intake (RNI).<br />

For some nutrients, a “safe intake” is given, and <strong>for</strong><br />

carbohydrate and fat, individual minimum, maximum,<br />

and population averages are specified [10].<br />

LRNI (lower reference nutrient intake)<br />

Using a statistical distribution of nutrient requirements,<br />

the LRNI is set at 2 standard deviations (SD) below the<br />

mean or average intake (EAR).<br />

EAR (estimated average requirement)<br />

The British EAR is the intake that meets the estimated<br />

nutrient needs of half of the individuals in a group,<br />

assuming a normal, statistical distribution of requirements.<br />

RNI (reference nutrient intake)<br />

This term is set at 2 SD of the requirement above the<br />

EAR and will meet the needs of 97% to 98% of the<br />

population; it is similar to the US/Canadian RDA.<br />

Safe intake<br />

A safe intake is specified <strong>for</strong> a nutrient <strong>for</strong> which there<br />

is insufficient data to determine a statistical distribution<br />

of requirements. The safe intake is judged to be<br />

a level or range of intakes at which there is no risk of<br />

deficiency and below a level where there is a risk of<br />

undesirable effects. The safe intake corresponds conceptually<br />

to the US/Canadian AI.<br />

Individual minimum, maximum, and population averages<br />

These terms are used by the British to specify recommended<br />

intakes of carbohydrate and fat [9, 10].<br />

European Communities terminology<br />

PRI (population reference intake)<br />

J. C. King et al.<br />

This term was introduced by the Commission of the<br />

European Communities in 1993 [12] to refer to an<br />

intake acceptable <strong>for</strong> a defined age- and sex-specific<br />

group. Like the US/Canadian RDA and the British<br />

RNI, it is <strong>based</strong> on a statistical distribution of requirements<br />

<strong>for</strong> a nutrient and is set at 2 SD above the mean<br />

requirement.

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