Transcript DRI`s - frozencrocus.com

Dietary Reference Intakes
Food pyramid(s) are devised based on
the food choices that are necessary in
order to meet the Dietary Reference
Intakes.
Different pyramids can be constructed
based on the biases of the “author”.
By following the food-serving
recommendations of the USDA food
pyramid , one would meet all of the
nutrient requirements recommended by
the DRI.
Because the USDA is a political body,
some of the food servings have been
derived based in part on lobbying efforts
by certain elements within the food
industry; meat, for example.
Healthy Lifestyle
Food Pyramid
©C. Murray Ardies
The Healthy Lifestyle Food
Pyramid* also meets the DRI
but is vegetarian-based &
provides a phytochemical-rich
diet that promotes prevention
of a variety of chronic diseases
and it includes specific
requirements for exercise to
enhance prevention .
The meat component is
optional because the nutsseeds-beans-legumes
component comprises a meatsubstitute and the only meat
recommendation is 2 servings
of fish/week.
*Optimal Health Guide – Stipes
Publishing, LLC, Champaign Illinois,
http://www.stipes.com/health.html
A Brief History
Canadian National Institute of Nutrition (Health Canada)
1990 Symposium - Should RNI’s be Revised?
Food And Nutrition Board IOM-NAS (USA)
1993 Symposium - Should RDA’s be Revised?
Food & Nutrition Board
Canadian National Institute of Nutrition
1995
Created the Standing Committee on the
Scientific Evaluation of Dietary Reference Intakes
To revise existing nutritional standards based on new information to create
Nutrient-Based Recommendations to Serve North America
IOM Publications (DRI)
1997 - Calcium, Phosphorus, Magnesium, Vitamin D &
Fluoride
2000 - Thiamin, Riboflavin, Niacin, B6, Folate, B12,
Pantothenic Acid, Biotin, & Choline
- C, E, Selenium Carotenoids
2001 - A, K, Arsenic, Boron, Chromium, Copper, Iodine,
Iron, Manganese, Molybdenum, Nickel, Silicon,
Vanadium & Zinc
2002 - Energy, Carbohydrate, Fiber, Fat, Fatty Acids,
Cholesterol, Protein & Amino Acids
2004 - Water, Potassium, Sodium, Chloride & Sulfate
Dietary Reference Intakes
Replace the RNI and RDA for Healthy Individuals
Estimated Average Requirement:
EAR
Recommended Dietary Allowance:
RDA
Adequate Intake:
AI
Tolerable Upper Limit:
UL
Based on:
Research Experiments/Surveys:
Consumption
Disease Incidence
Disease Prevention
Biochemical Function
Biochemical correlates associated with nutrient
function are used to determine adequacy.
The recommendations are based on the distribution of
the specific analyses within the target population
(including specific function and its relation to
disease and disease prevention).
Thus the DRI’s are really statistical estimates of
population parameters related to
nutrient intake & health.
DRI’s
EAR
RDA
AI
UL
Use to examine the possibility of inadequate reported intake
Usual intakes at this level have a low possibility of inadequacy
Usual intakes at this level have a low probability of inadequacy
Usual intakes above this level have a risk for adverse effects
RDA & Health
Inclusion of health indices has altered some RDA’s
dramatically (a few examples):
Vitamin C
+ 25%
♀
&
♂
Folic Acid
+ 100% ♀
&
♂
Vitamin E
+ 100% ♀
&
+ 50% ♂
Iron
+ 20%
♀
&
- 20% ♂
Copper
- 50% ♀
&
♂
A Wee Bit of Diet Analysis Stuff …
Evaluation of true nutritional status requires clinical,
biochemical, and anthropomorphic data
Diet analysis requires an accurate measure of usual
intake and addresses the question:
Is an individuals dietary intake adequate to meet their
Nutritional Requirements?
To be adequate an individuals usual intake (y) should be
equal to or exceed the individuals requirement for that
nutrient (p):
If y > p then y is adequate
If y < p then y is inadequate
An individuals actual nutritional requirement (p) is unknown
An Individuals usual intake (y) is unknown
Because the DRI’s are statistical constructs a statistical
approach is necessary
EAR is used as an estimate of r and SD of r is proportional to
the uncertainty about how accurately r estimates p.
Mean intake over n days (y) is used as an estimate of y and SD
of y is proportional to the uncertainty about how accurately y
estimates y.
For practical purposes y and r are used instead of y and p
and the difference (D) between y and r is used to make
inferences regarding adequacy of the diet
D = y - r
Because of uncertainty of both y and r, SDD must be
calculated and the ratio of D / SDD is used to construct a
level of confidence
SDD
=
√V
r
+ (Vwithin / n)
Use z-score values to determine levels of confidence for the
D/SDD ratio