Dietary carbs

Question 1

1. Describe how to calculate the number of grams of carbohydrate consumed per day by an individual in energy balance.

Answer 1

total amount of carbohydrate eaten is a function not only of the % carbohydrate in the diet, but of the total EI.
we can estimate EI using a formula for EE, then multiply the EI by the fraction of the diet attributable to each macronutrient to obtain the number of calories of each macronutrient consumed per day. Then by knowing the average energy density of each macronutrient (carb= 4 kcal/g, protein=4 kcal/g, fat=9 kcal/g, alcohol=7 kcal/g) an estimate of the number of grams per day of each nutrient can be calculated. For a typical 70 kg man, with a diet containing 15% protein, 35% fat and 50% carbohydrate, the number of grams of carbohydrate consumed per day is (2,100 x 0.5)/4=262 grams.

Question 2

2. List the chemical characteristics of sugars, oligosaccharides and polysaccharides.

Answer 2

1

Question 3

3. Compare and contrast the properties of resistant starch and fiber.

Answer 3

different bond, that cant be broken in humans

Question 4

4. Describe the concepts of glycemic index and glycemic load.

Answer 4

Glycemic index describes how a food raises blood glucose, glycemic load is amount of a food with glycemic index

Baguette, white, plain (France)
~95, 48
Banana, Mean of 10 studies
~52, 10
Carrots, Mean of 4 studies
~47, 3.5
Corn tortilla (Mexican)
~52, 25
Potato, Mean of 5 studies
~50, 9.3
Rice, boiled white, mean of 12 studies
~64, 15.4
Watermelon
~72, 3.6

Question 5

5. List the types of studies that can be used to inform nutritional recommendations.

Answer 5

animal or in vitro- mechanisitc information

epidemiologic study- self reporting, how do u measure endpoints

short term intervention trials- problems with power, diet control and endpoint

Long term intervention trials- Gold standard

Question 6

6. Describe the biochemical pathways involved in the metabolism of fructose and galactose.

Answer 6

fructose bypasses key regulatory step of glycolysis, comes in at 3 carbon level at glyceraldehyde phosphate. causes more visceral fat build up, and higher triglyceride level

Question 7

7. Describe the clinical presentation of disorders of fructose and galactose metabolism.

Answer 7

1

Question 8

High carb diet and diabetes

Answer 8

Increased intake of total carbs, increased intake of refined carbs (especially high fructise corn syrup) reduced intake of whole grain carbs in associated with DM

Question 9

fiber and diabetes

Answer 9

more fiber less diabetes

Question 10

glycemic load and diabetes

Answer 10

more glycemic load more diabetes

Question 11

what do long term intervention trials tell us?

Answer 11

high carb/ reduced fat and calorie restricted diet prevents diabetes

there were confounders. low carb diet helps in wt loss