dri - cho fiber

Question 1

Dietary Carbohydrates: Sugars and Starches

Answer 1

• EAR set for all age groups
– 100 g/d for children and adults
– 135 g/d for pregnancy & 160 g/d for lactation
• RDA add 2SD of 15% [EAR x 1.3]
– 130 g/d for children and adults

Question 2

Dietary Carbohydrates: Determining

Requirements

Answer 2

• Based on average minimum amount of glucose utilized by the brain
•Glucose use by the brain determined by A-V difference across the
brain in humans
• Recommended amount also prevents ketosis
130 grams of glucose / day = 520 kcal

Question 3

Dietary Carbohydrates: Sugars and
Starches

UL

Answer 3

UL not set because of insufficient evidence
– However, maximal intake 25% of energy from
added sugar
• defined by USDA as sugars and syrups that are
added to food during processing/preparation
• major sources include soft drinks, cakes,
cookies, pies, fruitades, fruit punch, dairy
desserts, and candy
• No recommendations based on glycemic
index (GI) or glycemic load since
insufficient evidence on the prevention of
chronic diseases

Question 4

Conclusion on

Glycemic Index/Glycemic Load

Answer 4

A UL based on GI was not made, primarily
because the critical mass of evidence
necessary for recommending substantial
dietary change is not available
• However, the principle of slowing
carbohydrate absorption…is a potentially
important principle. Further research in this
area is needed.

Question 5

Acceptable Macronutrient

Range

Answer 5

AMDR = 45 – 65% of energy for children and
adults
– old RNIs and RDAs values 50-55%
• Carbohydrate: 45 – 65% of kcals
– Lower than 45%
• Difficult to meet AI for total fiber
• Fat may be too high, increase in obesity
– Higher than 65%
• May lead to hypertriglyceridemia
• Fat or protein may be too low

Question 6

Median Intake of

Carbohydrates

Answer 6

• 200-330 g/d for men
• 180-230 g/d for women
– Issue, however, in low-carb diets

Question 7

Dietary, Functional, and Total Fiber

Answer 7

Total Fiber = Dietary Fiber + Functional
Fiber
• Dietary Fiber = nondigestible CHOs and
lignin that are intrinisc in plants and that
are not digested and absorbed in the
small intestine
• Functional Fiber = isolated
nondigestible CHOs that have
demonstrated beneficial physiological
effects in humans

Question 8

Fiber: Determining Requirements

Answer 8

• First time recommendations made for fiber
• No biochemical assay that can be used to
measure fiber nutritional status
• Blood fiber levels cannot be measured
because fiber not absorbed
• Health benefits used to determine DRIs
Based on level that protects against CHD
• Diabetes secondary endpoint to support
recommended level
• Fiber and colon cancer association not clear
• Fiber may improve constipation and diverticular
disease, provide fuel for colonic cells, reduce
blood glucose and lipid levels and provide
source of low energy, nutrient rich foods but
these benefits not used to set AI

Question 9

Dietary, Functional, and Total Fiber

ul, ai

Answer 9

AI set for Total Fiber all age groups
– 14 g/1000 kcal per d for children and adults
• 38 g/d for males 14-50 y
• 30 g/d for males >51 y
• 25 g/d for females 14-50 y
• 21 g/d for females >51 y
• 28 g/d for pregnancy & 29g /d for lactation
– current intake less than half of AI
UL not set because excess consumption is
likely to be self-limiting
• concerns include mineral bioavailability,
gastrointestinal distress, low energy intakes