1. Carbohydrates

2. Intended Learning Outcomes
By the end of this lecture, students will have a general overview on the carbohydrates.

3. Fiber structural parts of plants found in all plant derived food
bonds of fibers cannot be broken down during the digestive process
minimal or no energy available

4. Fiber types pectins lignins resistant starches classified as fibers
cellulose
pectins
lignins
resistant starches
classified as fibers
escape digestion and absorption

5. Fiber Characteristics
soluble fibers, viscous, fermentable
easily digested by bacteria in colon
associated with protection against heart disease and diabetes
lower cholesterol and glucose levels
found in legumes and fruits

6. Fiber The average American does not get enough FIBER in their diets.
The National Cancer Institute recommends that the average person gets GRAMS of fiber every day.
Two other common names for fiber are: ROUGHAGE or CELLULOSE.

7. Fiber is important because it attracts WATER to the INTESTINES and helps move food through our systems faster. You have to have water along with fiber or it is not as effective.
Benefits of fiber include a lowered risk of DIVERTICULITUS, HEMORRHOIDS and COLON or RECAL CANCER.

8. 6. List the two types of fiber and the main functions they perform:
Type of Fiber
Function
A. Soluble
Shown to lower total blood cholesterol
Insolubl
*Will NOT digest or dissolve
Helps move food through the body

9. Fiber only comes from PLANT food sources
Fiber only comes from PLANT food sources. You CANNOT get fiber from animal food sources.
Foods that are high in fiber include:
Fruits and Veggies (Especially the Skins!)
Whole Grains
Legumes/Beans - Bran
Ways to increase fiber in the diet include:
Add Whole Grains (At least 3 oz. per day)
Use Whole Wheat FlourEat the Skins

10. 10. Label the Wheat Kernel below:
__ENDOSPERM___
Provides:
Starch
Protein
__Bran___
Provides:
Fiber
Vitamins
Minerals
__GERM___
Provides:
Unsaturated Fatty Acids
“B” Vitamins
Vitamin E
Iron
Zinc
Other Trace Minerals

11. When a product claims that it is “Whole Wheat” or “Whole Grain”, it must use the ENTIRE wheat kernel, or ALL THREE parts.
Other products, like white bread and rice, usually only use the ENDOSPERM, which is the LEAST beneficial part of the wheat kernel.
ENRICHED: some of the nutrients that were lost in processing are added back into the product.
FORTIFIED: 10% more of the Daily Value for the nutrient is being added.

12. Fiber insoluble and not easily fermented promote bowel movements
alleviate constipation
found in grains and vegetables

13. DRI and Fiber distinguish fibers by source
dietary fibers: naturally in intact plants
functional fibers: extracted from plants or manufactured
total fiber: sum of the 2

14. Carbohydrate Digestion
break down into glucose
body is able to absorb and use
large starch molecules
extensive breakdown
disaccharides
broken once
monosaccharides
don’t need to be broken down

15. Carbohydrate Digestion
begins in mouth
chewing releases saliva
enzyme amylase hydrolyzes starch to polysaccharides and maltose
stomach
no enzymes available to break down starch
acid does some breakdown
fibers in starch provide feeling of fullness

16. small intestine majority of carbohydrate digestion takes place here
pancreatic amylase reduces carbs to glucose chains or disaccharides
specific enzymes finish the job
maltase
maltose into 2 glucose
sucrase
sucrose into glucose and fructose
lactase
lactose into glucose and galactose

17. large intestine
1-4 hours for sugars and starches to be digested only fibers remain
attract water, which softens stool
bacteria ferment some fibers
water, gas, short-chain fatty acids (used for energy)

18. Carbohydrate Absorption
glucose can be absorbed in the mouth
majority absorbed in small intestine
active transport
glucose and galactic
facilitated diffusion
fructose
smaller rise in blood glucose

19. Lactose Intolerance more lactose is consumed than can be digested
lactose molecules attract water
cause floating, abdominal discomfort, diarrhea
intestinal bacteria feed on undigested lactose
produce acid and gas

20. Lactose Intolerance age, damage, medication, diarrhea, malnutrition
management requires dietary change
6 grams (1/2 cup) usually tolerable
take in gradually
hard cheeses & cottage cheese
enzyme drops or tablets
lactose free diet is extremely difficult to accomplish

22. Carbohydrate Metabolism
1/3 of body’s glycogen is stored in liver
released as glucose to bloodstream
eat – intake glucose
liver condenses extra glucose to glycogen
blood glucose falls
liver hydrolyzes glycogen to glucose
Glycogen is bulky, so we store only so much: short term energy supply
Fat is the long term energy supply.

23. Glucose for Energy enzymes break apart glucose – yielding energy
inadequate supply of carbohydrates
ketone bodies (fat fragments) are an alternate energy source during starvation
excess ketones can lead to ketosis: imbalance of acids in body
minimum of 50 – 100 grams of carbs/day are needed to avoid ketosis

24. Glucose Homeostasis
maintaining an even balance of glucose is controlled by insulin and glucagon
insulin
moves glucose into the blood
glucagon
brings glucose out of storage

25. maintaining balance
balanced meals at regular intervals
fiber and some fat slow the digestive process down
glucose gets into the blood slow and steady

26. Maintaining Blood Glucose Homeostasis1
Intestine
When a person eats,
blood glucose rises.
Maintaining Blood Glucose Homeostasis 2
High blood glucose stimulates
the pancreas to release insulin.
Pancreas
Insulin 3
Insulin stimulates the uptake of glucose into cells and storageas glycogen in the liver and muscles. Insulin also stimulates the conversion of excess
glucose into fat for storage.
Liver
Fat cell
Muscle 4
As the body's cells use
glucose, blood levels decline. 5
Low blood glucose stimulates
the pancreas to release
glucagon into the bloodstream.
Pancreas
Glucagon 6
Glucagon stimulates liver
cells to break down glycogen
and release glucose into the
blood.a
Glucose
Insulin
Glucagon
Glycogen
Liver
a The stress hormone epinephrine and other hormones
also bring glucose out of storage. 7
Blood glucose begins to rise.

27. Imbalance
diabetes
after food intake, blood glucose rises and is not regulated because insulin is inadequate
hypoglycemia
blood glucose drops dramatically
too much insulin, activity, inadequate food intake, illness
diet adjustment includes fiber-rich carbs and protein

28. Glycemic Index
way of classifying food according to their ability to raise blood glucose
much controversy

30. Sugar ½ comes from natural sources, ½ from refined and added
sucrose, corn syrup, honey
excess can lead to nutrient deficiencies and tooth decay
empty calories
sugar and starch break down in the mouth

31. Sugar recommended intake
added sugar = no more than 10% of energy intake

33. Starch and Fiber diet that includes starch, fiber and natural sugars
whole grains, vegetables, legumes, fruits
may protect against heart disease and stroke
reduces the risk of type 2 diabetes
enhances the health of the large intestine
can promote weight loss

34. Starch and Fiber starch intake 45-65%
225 – 325 grams (DV is 300 grams)
kcal/2000 kcal
RDA is 130 grams
fiber intake
Daily Value is 25 grams/2000 kcal

37. Groceries grains: 1 serving = 15 grams vegetables
½ cup starchy = 15 grams
½ cup nonstarchy = 5 grams
fruit: 1 serving = 15 grams
milk: 1 cup = 12 grams
meat: none or little
legumes: ½ cup = 15 grams

38. Artificial Sweeteners
help keep sugar and energy intake down
anything we eat has FDA approval
saccharin
aspartame
acesulfame potassium
sucralose
neotame

40. Recommended text book
Manual dietetic book