Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

food energy and nutrients > dietary reference values > Flashcards

dietary reference values Flashcards

1
Q

how can we tell if people manage sufficient amounts of nutrients to maintain adequate health

A

by comparing their intakes with recommendations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

who were DRVs published by in 1991

A

DoH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

whys it important to set standards for nutrient intake

A

To prevent deficiency symptoms.

To optimise body stores of a nutrient. E.g. to optimise vit D stores

To optimise a biochemical or physiological function. E.g. need sufficient amount of nutrient if its maybe a cofactor for an enzyme to work

To minimise risk factor for some chronic disease. E.g. reducing sat fatty acid intake reduces levels of cholesterol so reduce CHD

To minimise incidence of a disease. E.g. increase fibre intake reduce risk of colorectal cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what was the name of the USAs first version od dietary standards produced in 1943 by the national research council

A

the Recommended Dietary Allowances (RDAs).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what did the RDAs in 1943 aim to provide

A

a yardstick against which diets or food supplies could be assessed to determine their adequacy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how many nutrients did the RDAs provide info on in 1943

A

10 nutrients
Modern day equivalents provide info on about 30 or more nutrients.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

when were the UK Recommended Daily Intakes (RDIs) and the UK Recommended Daily Amounts (RDAs) introduced

A

1969 UK Recommended Daily Intakes (RDIs)
1979 UK Recommended Daily Amounts (RDAs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what happened to the name of the RDAs in 1991

A

Nomenclature changed – ‘recommended’ led many to believe it represented min desirable intake for health.
so name changed to UK Dietary Reference Values (DRVs) published.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what did the DRVs apply to

A

Apply to the range of intakes based on an assessment of the distribution of requirements for each nutrient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

who did the DRVs apply to

A

heathy people

Not appropriate for those with disease or metabolic abnormalities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DRVs for 1 nutrient presuppose what

A

that requirements for energy & all other nutrients are met.

e.g. prot & vit A – If vit A req met but not prot, insufficient RBP to transport vit A. – nutrients work together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why do you need to use caution when assessing diets of individuals with the DRVs

A

so making sure that you don’t use any strong statements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are uses of DRVs

A

Assessing diets of individuals - Use caution!

Assessing diets of groups of people and populations.

For providing guidance on composition of meals and diets.

Food labelling e,g, reference intake on food packaging are based on DRVs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

name the 3 levels that the UK 1991 COMA (Committee on Medical Aspects of Food Policy) panel set for DRVs

A

Estimated Average Requirement (EAR)

Lower Reference Nutrient Intake (LRNI)

Reference Nutrient Intake (RNI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the EAR

A

Estimated Average Requirement (EAR)
Average requirement that Will meet the needs of 50% of the whole population.

half od pop will usually need > EAR. half will need less.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the LRNI

A

Lower Reference Nutrient Intake (LRNI)
Will meet the needs of 2.5% of the whole population.

Situated 2 SD below EAR.

LRNI equivalent to 1969 RDI.

In many countries LRNI is only figure used.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the RNI

A

Will meet the needs of 97.5% of the whole population.

Situated 2 SD above EAR.

RNI includes margin of safety – individuals with intake just below RNI may have sufficient intake.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

if nutrient intake is greater then RNI then the individuals intake can be classed as

A

almost certainly adequate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

if individuals intake is <EAR and < RNI then their intake can be classes as

A

likley to be adequate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

If intake is > LRNI and < EAR then the individuals intake can be classed as

A

likely to be inadequate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

If intake is < LRNI then individuals intake can be classed as

A

almost certainly inadequate for most individuals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

why can we say someone is deficient if they’re nutrient intake is below the RNI and even well below the EAR

A

as it may be sufficient to their needs

23
Q

If mean for group is around the RNI most subjects should be what

A

okay

24
Q

if mean for a group is around the EAR then subjects might be what

A

all subjects might be OK but more likely some will not be.

25
Q

If mean for a group is at the LRNI then subjects will what

A

not have enough

26
Q

why can RNIs for all nutrients (not energy) can be set at the upper range of requirements

A

as an intake moderately in excess of requirements has no adverse effects, but decreases the risk of deficiency.

27
Q

what is the only measurement given for energy intake

A

EAR

28
Q

what do individual requirements of energy depend on and why

A

BMR and PAL

cos these are the main components of energy expenditure

29
Q

what is total energy expenditure equal to

A

BMP times PAL

30
Q

wheres excess energy stored

A

in adipose tissue

31
Q

a BMI between what is the ideal weight range

A

18.5 and 24.9

32
Q

in 2011 BMR predicted using healthy reference body weights, so what did this do to people overweight who followed the recommended amount

A

they lost weight

33
Q

how do we estimate BMR

A

measure our energy expenditure using calorimetric methods and we can estimate it using equations

Can calculate without height but it gives an added level of accuracy

34
Q

there is no absolute requirement for what fats and carbs

A

fats, sugars or starches.

except for the essential fatty acids:
(linoleic acid (n-6) – sunflower, corn oil
Alpha-linolenic acid (n-3) – linseed, canola, soybean oil)

35
Q

Panel on DRVs made judgements based on the changes from current intakes that would be expected to result in certain changes in what

A

physical and/or heath outcomes

36
Q

for fat and carbs DRVs are given as… and how are they expressed

A

as population average, individual minimum and individual maximum.

And expressed as percentage of our energy intake rather than grams per day

37
Q

DRVs for fat are based on change in what

A

serum cholesterol needed to decrease CHD risk.

38
Q

what is safe intake

A

A level or range of intakes at which there’s no risk of deficiency and below a level where there’s a risk of undesirable effects.

39
Q

when is safe intake used

A

when not enough info to determine an LRNI, EAR or RNI

40
Q

for carb and fat requirements what 3 terms are used

A

individual minimum
individual maximum
population average

41
Q

why do we just have a safe intake for vitamins C and K recommendations

A

cos Some nutrients known to be important but there’s insufficient data on human required to set any DRVs

42
Q

what are DRVs for fat expressed as

A

% total E (% food energy)

43
Q

what do food energy sources include

A

that from protein, fat and carbs

44
Q

what do total energy sources include

A

energy from protein, fat, carbs and alcohol

45
Q

what does the total fat recommendation include

A

fatty acids and glycerol

46
Q

DRVs for carbs are expressed as what

A

% total dietary energy

47
Q

how were DRVs derived

A

Panel looked at, Observed intakes in populations without deficiency or excess.

Intakes known to match known losses or physiological requirements in healthy subjects (e.g. pregnancy, lactation, iron loss in menstruation).

Intakes associated with optimal level of some biological function. E.g. degree of enzyme saturation

Intakes which have been shown to cure deficiency (e.g. Vitamin C). 10mg/d sufficient to cure clinical signs of scurvy.

48
Q

what are limitations of DRVs

A

Often derived from experimental data limited to
certain groups (e.g. young men rather than women, healthy individuals ).

Limited info on certain groups e.g. children and elderly, or people w diseases.

Usually committees add a safety margin – varies between countries. E.g vit C varies between uk and usa

For some nutrients, where little is known about requirements, a safe level is given.

Requirements are a best guess!

Need to be updated every 10-15y to include new evidence.

49
Q

what causes variation in nutrition requirements between individuals

A

Age, sex, body size (Men have greater req due to body size & activity, except iron as they don’t menstruate)

Physiological state (e.g. infection, pregnant or breastfeeding women)

Digestion & absorption. E.g some people are lactose intolerant

Nutrient losses (e.g. amount of iron lost during menstruation)

Lifestyle (smoking, exercise, exposure to sunlight) e.g. Smokers have increased turnover of vit C + have increased req.

Interactions between nutrients. E.g. iron absorption inhibited by calcium

Drug-nutrient interactions. e.g Warfarin – drug given to people at risk of thrombosis but blocks action of vit K. (blood clotting).

Variations in physiological function

50
Q

reference intakes (RI) have replaced what on food labels

A

GDAs - guideline daily amounts was developed to communicate the Government’s recommendations.

have same principle now

51
Q

what were food labels initially set for

A

fat, SFA, salt, sugar and fibre in g/day for men and women.

52
Q

why do we need a balanced nutrient intake

A

to estimate requirements for certain nutrients where body pool remains constant: average daily loss of nutrient should balance intake.

Intake = Output
Intake < Output ….then intake inadequate.

53
Q

who are the Scottish dietary goals used by

A

Used by researchers and health promoters and policymakers and stakeholders who influence the diet of the population

54
Q

what are the Scottish dietary goals based on

A

DRVs

food energy and nutrients (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions