Lecture 12: How good is this group's nutrient intake?

Question 1

Why is information on group intake important?

Answer 1

1. Monitor population intakes
2. Identify problem nutrients for a population
3. Plan programmes to address problem nutrients

Question 2

How is EAR used in groups?

Answer 2

Used to estimate the prevalence of inadequate intakes within a group

Question 3

How are RDI’s used in groups?

Answer 3

You don’t use RDI’s for groups

Question 4

How is AI used for groups?

Answer 4

Mean usual intake at or above AI implies low prevalence of inadequate intakes

Question 5

How is UL used in groups?

Answer 5

Used to estimate %age of population at potential risk of adverse effects

Question 6

What is the EAR cutpoint method?

Answer 6

The EAR cutpoint method estimates the prevalence of inadequate nutrient intakes by determining the percentage of individuals whose intake falls below the Estimated Average Requirement (EAR). It is simple and works well when nutrient requirements are normally distributed.

Question 7

What is the Probability approach?

Answer 7

The probability approach calculates the likelihood that an individual’s nutrient intake is inadequate by taking into account the full distribution of both nutrient intakes and nutrient requirements. It is especially useful for nutrients with highly variable or skewed requirements, such as iron.

Question 8

Probability approach vs EAR cut point method

Answer 8

While the EAR cutpoint method is easier to apply and works well for nutrients with normally distributed requirements, the probability approach provides a more accurate estimate for nutrients with variable or skewed requirement distributions, offering a precise view of nutrient inadequacy in a population.

Question 9

Can AI be used to determine prevalence of inadequate intake in a group?

Answer 9

No

Question 10

If mean intake of a group is at or above AI…

Answer 10

Prevalence of inadequate intakes is probably low

Question 11

If mean intake of a group is below AI…

Answer 11

You can’t do anything, it can’t determine inadequacy

Question 12

What does AI assume?

Answer 12

• That the variance of intake is similar to that of population AI is based on
• AI is based on mean intake of a healthy population

Question 13

Using UL for groups is a similar approach to….

Answer 13

EAR cutpoint method i.e. determine proportion of gp with intake >UL

Question 14

How do we ensure we are using appropriate intake distribution?

Answer 14

Remember:
- Some nutrients need intake from all sources e.g. vit C
- Some nutrients only need suppl intake e.g. vit E

Question 15

We can’t use EAR cut-point or Probability methods to identify….

Answer 15

Specific people with inadequate intake

Question 16

The full probability approach is ??? consuming

Answer 16

Time

Question 17

We don’t have ?? for all nutrients

Answer 17

EAR

Question 18

You shouldn’t compare ??? to EAR or RDI

Answer 18

Group mean intakes

Question 19

You shouldn’t use EAR cut-point method to assess….

Answer 19

Fe intake in premenopausal women

Question 20

You shouldn’t use EAR cut-point method for ??? groups

Answer 20

Small (<30)

Question 21

What does the EAR cut-point method assume?

Answer 21

• No correlation between intakes and requirements
• Distribution of requirements is symmetrical
• Variance of intakes > variance in requirements
• Prevalence of inadequate intakes is neither very high nor very low (ideally 10-90%)

Question 22

What does the probability approach assume?

Answer 22

• That there is no correlation between intakes and requirements

Question 23

When must the probability approach be used?

Answer 23

• For Fe in premenopausal women
• If prevalence of inadequate intakes is very high or low in the population

Question 24

What does the EAR cut-point method use?

Answer 24

Uses the percentage of people with intakes below the EAR as an estimate of the prevalence of inadequate intakes

Question 25

What does the full probability approach use?

Answer 25

Uses data on the probability of inadequacy at the different intake levels seen in the group to estimate the prevalence of inadequate intake

Question 26

What is the first step to determining nutrient adequacy in groups?

Answer 26

Collect multiple days dietary data
- Diet record or 24hr recall

Question 27

What is the second step to determining nutrient adequacy in groups?

Answer 27

Adjust intake distribution:
- Adjust distribution to remove day-to-day variability in intakes

Question 28

What is the third step to determining nutrient adequacy in groups?

Answer 28

Use EAR to determine adequacy using either:
- EAR cut point method
- Probability approach

Question 29

What are the 3 steps of the probability approach?

Answer 29

1. Construct a risk curve
2. Determine % intakes in each risk category
3. Determine prevalence of inadequacy