Module 4 - Carbohydrates and Fibre Flashcards
What is a Carbohydrate?
Sugar Molecules
- Energy source
- Control blood glucose and insulin metabolism
What is a monosaccharide give 3 examples
Single unit which contain carbon chain of 3 or 6 carbons
- Produce and store energy
- Examples: Glucose, Galactose, Fructose
What is a disaccharides and give 3 examples.
Carbs that consist of two or more monosaccharides linked together.
- Act as an energy source
- Examples: Sucrose, Maltose, Lactose
Two type of CHO (Carbs)
- Simple - Broken down quickly by the body. (MONO and DI-saccharides
- Complex - made of sugar in long complex chains. (STARCH)
Polysaccharide’s
Hundreds of sugar units in length
Your liver stores _________?
Glycogen
Cellulose is digested T or F
False
Oligosaccharides and Examples
3-10 sugar units
Lentils and artichokes.
Carbs in diets
DRI Value: 45-65% for CHO
Examples of Carbs
-Potatoes, Corn, Carrot
-Banana, (Starch sugars)
-Starch
-Soy beverage (cane sugar)
-legumes, nuts, seeds
Compare Carb intake from around the world. (Africa, Caribbean, NA)
Africa - 80% Kcal from carbs
Caribbean - 65% Kcal from carbs
NA - 53% from carbs
Similarities and Differences between glycogen and starch.
Similar
- Complex Carbs
- Stored as Granules for energy
- Both made of glucose
Differences
- Glycogen is more branched
- Glycogen is produced in liver animals.
- Starch is found in plants.
Carb Digestion and Absorption
- MOUTH: some starch is broken down to salivary amylase –> Maltose (G-G)
- STOMACH: HCL denatures/inactivates salivary amylase
- SMALL INTESTINE: Digestion begins
- Starts as starch
- Enzyme: Pancreatic Amylase decreases
- Results: Maltose (G-G)
- Maltose -> Maltase -> 2 Glucose
- All absorbed into blood
- Transferred to liver via portal vein.
Monosaccharide metabolism - In Liver
- In Liver
a) Fructose and Galactose = Glucose
b) Glucose - Used for energy
i) Liver glycogen
ii) Makes nonessential amino acids
iii) Converted to fat then goes to VLDL
iv) Enters blood stream
Monosaccharide Metabolism - In Blood stream
- Used for fuel by all body cells (Brain, CNS, RBC)
- Muscle Glycogen
Glucose
Primary fuel for Brain and Red Blood cells
- Found in very small amounts in some fruits
What happens to glucose when it is released from liver?
It rises blood glucose after eating sends a signal to pancreas to produce insulin
Insulin allows
- Uptake of glucose by body cells
- Stimulate glycogen synthesis
- Returns blood glucose to normal levels.
What happens when blood glucose levels begin to fall?
- Blood glucose drops (Hunger Pangs)
- Pancreas decreases Insulin - Mobilizes
- Glycogen -> G-G-G - Results
- Blood glucose increases (normal blood glucose leads)
- Stops hunger pangs.
Type 1 Diabetes
5% of people
- Inability of pancreas to make insulin
- genetic predisposition
- Must take insulin
Type II Diabetes
95% - obesity + Physical Inactivity
- Body cells ignore insulin
- Primary Treatment: Exercise + Diet
- Metformin (Increase sensitivity)
Glucose Tolerance
A measure of a person’s ability to remove excess blood glucose following a meal
Glucose Tolerance Test
- Give pure glucose drink
- Take blood samples every 30 mins, over 2-3 hours
- Blood glucose levels will rise
- Pancreas responds and produces insulin - results of blood samples are plotted on a graph
Glycemic Response
Blood glucose response after eating.
ex/
- White bread or boiled potato - Higher curve of blood glucose but drops quickly
- Whole wheat (Baked Potato) (legume) - Lower curve which lasts longer
WHOLE WHEAT has better glycemic response
Fructose food sources
Food sources:
- Honey
- Fruit: fiber, V/M less Kcal (phytochemicals)
- High fructose Corn syrup
Fructose function
energy fuel for synthesis of glycoproteins and glycolipids
HFSC contributes to obesity epidemic T or F?
True
Disaccharides: Sucrose
- table sugar
-Isolated/purified from sugar beet or sugar cane.
Body tissues that rely on glucose for energy
Brain, Red Blood Cells
Insulin and glucagon in maintaining blood glucose concentrations
Insulin - enables blood glucose to enter cells, where they use it to produce energy.
Glucagon - Breaks down glycogen to glucose in the liver.
Helps maintain balance and homeostasis.
Hydrolysis and condensation reaction refer to using examples.
Hydrolysis: use water to break a molecule into smaller molecules.
Example: Digestion of food.
Condensation: smaller molecules combine to form a bigger molecule, with loss of small molecule like H2O
example: to amino acids to form a peptide bond.
Key characteristics of Glucose Tolerance Test Graph
- If curve is over 10 blood glucose They would have diabetes.
- at 10ml you reach urinary threshold
- Diabetes if a high spike then drop quick
- Treated or Non-diabetic have a small bump that reaches 10ml then comes down and stays level.
what is meant by urinary or renal threshold
concentration of a substance in the blood at which the kidneys begin to remove it into the urine
High Fructose Corn Syrup contributes to obesity epidemic
- Body uses Fructose differently from other sugars:
- Doesn’t stimulate insulin secretion
- Stimulates liver fat synthesis - Humans have never consumed anything close to the current levels of fructose
- just 1 daily 16oz (2 cups) of soda can add up to 20lbs weight gain a year
oligosaccharides impact on gut health
positive influence.
Debunk sugar myths
- dental cavities
- glucose intolerance
- Diabetes
- Dyslipidemia
- CHD
- ADHD
- Obesity
They all are false except cavities
They play a factor but main factor is over eating.
Do sugars cause Obesity
- Trend with ‘low fat’ (9Kcal/g)
- move the fat replace it with as many or more Kcal from sugar. = Weight gain. - Form of carb affects satiety (full)
a)Kcal in liquid form isn’t filling
b) foods providing simple sugars refined carbs (white flour based) less filling than complex carbs+fibre - Sugars have no nutritional value = EMPTY KCAL.
Should you choose Nutrient dense or calorie dense.
Nutrient dense is healthier.
So Do sugars really cause obesity?
NO - its food choices that cause obesity not sugar itself.
Lactose intolerance
digestive condition that makes it difficult to digest lactose, Sugar found in milk
Milk allergy
typical immune system response to milk and products.
examples of Oligosaccharides
Plus good food souces
Lactose, Maltose, Sucrose
good food sources:
- Lentils
- Artichokes
- Kale
- Wheat
- Watermelon
Example of sugar alcohols
Food sources
xylitol, mannitol, sorbitol
Food Sources:
- Mints
- Pineapples
- Berries
- Peaches
- Apples
Dextrins, resistant starch
Dextrins - variety of products by heating starch in presence of moisture and an acid.
Resistant starch - type of carb that doesn’t get digested in your small intestine
Soluble Fibre + Food sources
Soluble fibres - dissolves in water and turns to a gel during digestion (slows digestion)
Food examples
Oat
Barley
Nuts
Seeds
Lentils
Beans
Insoluble Fibre + Food sources
stays unchanged while going through the digestive system helps with bowel regularity
Food Examples:
Whole wheat flour
Cauliflower
Green beans
Potatoes.
Consequences of Undigested Lactose:
Lactose enters small intestine
Lactose undigested travels through small intestine and attracts water
Lactose enters colon
Lactose is excreted by resident microbes which results in diarrhera
Lactase Deficiency
Losing ability to make LACTASE
Around age 3-16
