NTRI 2000 Week 5 Notes
Popular in Nutrition and Health
Popular in Department
This 12 page Class Notes was uploaded by Alyssa Anderson on Tuesday February 9, 2016. The Class Notes belongs to NTRI 2000 at a university taught by Dr. Greene in Spring 2016. Since its upload, it has received 35 views.
Reviews for NTRI 2000 Week 5 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/09/16
Nutrition 2000 Week 5 Notes Carbohydrates A. Main fuel source for: 1. The brain 2. Nerve cells 3. Red blood cells (RBCs) 4. Exercising muscle B. Form of carbohydrates (for all cells) 1. Blood Glucose 2. Glycogen C. What’s the ultimate source of carbohydrates? The sun. D. Metabolism: H2O + O2 ——> energy + H2O + CO2 E. Simple Carbohydrates (Sugars) 1. Monosaccarides a. Mono = ONE sugar b. Basic unit of all carbohydrate structures c. Mainly glucose, fructose, galactose d. Check out the structures of the sugars (“not on test just good to know”) e. Dextrose- the major monosaccharide found in the body, called the blood sugar, and derived from the digestion of starches and disaccharides f. Fructose- converted to glucose and other compounds, also called fruit sugar sweeter than the others; one dietary source is high-fructose corn syrup (in soft drinks it is made up of approximately 55% fructose and 45% glucose) g. Lactose- part of the Image of the brain showing activity before and disaccharide lactose (known after consuming glucose and fructose as milk sugar) 2. Disaccharides a. di = two, meaning there is chemical bonding of two monosaccharides b. *Glucose is always one of the 2 sugars* c. Maltose = glucose + glucose d. Lactose = glucose + fructose e. Sucrose = glucose + fructose F.Complex Carbohydrates (Starches and Fiber) 1. Called polysaccharides or starch 2. May contain 1000 or more glucose units 3. Found in grains, vegetables, and fruits 4. On food labels, “other carbohydrates” refers to starch content 5. Starches are found in plants, especially potatoes A. They are digestible by humans B. Amylose makes up 20% of starches C. Amylopectin makes up 80% of starches D. Glycogen a. Identiﬁed in 1858 b. Highly branched, which is good for quick energy c. 1800 kcal present in humans d. 1400 kcals are stored in the muscle, but can be depleted (muscle fatigue/ “hitting a wall” e. 400 kcals are stored in the liver, and can be depleted in 18 hours f. It is also stored in the fat and brain Carbohydrates Conceptual Map Carbohydrate availability A. Cooking- softens ﬁbrous parts of plants B. Starch granules swell with water making it easier to digest C. M outh- the enzyme salivary amylase helps break down starch (not very important) and starts digestion as well as in the esophagus D. Stomach- the acid inactivates amylase, so no further starch digestion E. Small intestine- the alkaline environment promotes CHO digestion through enzymes Enzymes A. The sufﬁx -ase is used in biochemistry to indicate enzymes B. In the small intestine, pancreatic amylase breaks starches in sugars like di- and tri- saccharides C. Maltase, sucrase, lactase, dextrose (disaccharides) D. They are located in the brush border of the cells that line the inside of the small intestine Lactose Intolerance A. Caused by a decrease in lactase production 1. Lactase is high in infants then reduced in adults 2. If the lactase production does not decrease, it’s called lactase persistence, which often develops in early childhood 3. Symptoms include abdominal pain, gas, cramps, and diarrhea after consuming an amount of lactose 4. NOTE: how much is consumed is KEY 5. Highly associated with region/genetics Carbohydrate Absorption Carbohydrate Absorption A. Monosaccharides go to intestinal cells via transporter proteins B. They are then absorbed by capillary into the liver via the portal vein C In the liver, fructose and galactose are converted into glucose D. Glucose goes into the blood, is stored as glycogen, or converted into fat Functions of glucose in the body A. Supplies fuel (kcal) 1. In RBCs, the brain, and exercising muscle 2. Present in all cells B. Spares body proteins C. Maintains acid-base balance (pH) to prevent ketosis- a buildup of keno in blood from fat breakdown Blood glucose concentrations A. How do we regulate blood glucose? 1. Primary control- liver and pancreas 2. Secondary control- adrenal glands, brain, muscle B. High blood glucose- pancreas releases hormone insulin into blood C. Low blood glucose- pancreas releases hormone glucagon into blood D. Discovery of insulin- 1921; won the Nobel Prize of Medicine; before the 1920s, there was no cure 1. Experiment 1: removed the pancreas from a dog (practically gave the dog diabetes) which resulted in raised blood sugar, extreme thirst, frequent urination, and increasing weakness until ﬁnally, the dog died 2. Experiment 2: Scientists removed the pancreas, sliced it up, then froze it into a mixture of water and salts. When the pieces were half frozen, they were ground up and ﬁltered. The extract was then injected into the diabetic dog and the its diabetes was temporarily reversed (aka blood glucose went down) Functions of Insulin A. The net effect is that it lowers blood glucose B. How? Promotes glycogen synthesis C. Where? Muscle, liver and fat, but more often muscle D. What does it do? Increases glucose uptake by the cells and reduces glycogenesis Glucagon action in the liver A. Causes the liver to breakdown liver glycogen into glucose and releases it into the blood (glycogenolysis) B. Causes the liver to synthesize glucose from noncarbohydrate precursors (glycogenesis) Blood glucose and the adrenal glands A. Adrenal gland is located on kidneys B. Releases epinephrine which causes quick conversion of glycogen to glucose in the liver Improper regulation of blood glucose concentrations A. Hyperglycemia- high blood glucose diabetes- type 1, type 2, gestational B. Hypoglycemia- low blood glucose reactive hypoglycemia, fasting hypoglycemia Type 1 Diabetes A. Often begins in late childhood (also called juvenile diabetes) B. Generally associated with a decreased release of insulin from pancreas C. Immune system disorder (auto-immune disease) resulting in destruction of the insulin-producing cells D. Occurs when the body attacks beta cells thinking its a foreign cell E. Treated by insulin therapy- through pumps/shots, different types of insulins, NOT oral medications F. The goal is to stay in a normal range Type 2 Diabetes A. Most common form of diabetes, accounting for 90-95% of all cases B. Affects about 9% of the population in the United States C. Alabama ha the highest rate at 12.7% (Mississippi is 12.0%) E. Development- Why is it more prevalent in older folks? It is associated with obesity F. Genetics play a role in the development G. There is a stage before being diagnosed with Type 2 called “pre- diabetes” where the body becomes resistant to the effects of insulin so the body attempts to make more but fails. Then the pancreas produces less insulin which causes hyperglycemia. You can do a glucose tolerance test to assess glucose clearance. 1. Oral glucose tolerance test- 140 mg/dL but below 200 mg/dL 2. Fasting plasma glucose- above 100 mg/dL but below 126 mg/dL Diabetes outcome A. Increases the risk of cardiovascular disease, stoke kidney diseases, certain forms of caner, and blindness B. Sometimes, complications lead to adult blindness and lower limb amputation Diabetes treatment A. If associated with obesity, attempt to lose weight B. In general, diet, exercise, oral medications, insulin, and bariatric surgery (shrinks stomach/ removes sections from the stomach) Carbohydrate need A. Recommendations vary widely B. RDA recommends 130 grams/day for adults C. Food and Nutrition Board: 45-65% of calories need to be from carbs D. High carbohydrate intake 1. Grains- 15 g/serving 2. Fruits- 18 g/serving 3. Milk- 12 g/serving E. Low carbohydrate intake 1. Nuts- 4 g/serving 2. Meat and eggs- 0 g/serving 3. Vegetables- 5 g/serving Glycemic Index A. Ratio of the blood glucose response to a given food compared to a standard B. Based on 50 grams of carbohydrates C. Inﬂuenced by starch structure, ﬁber content, food processing and physical structure, and other macronutrients in food Glycemic Load A. Takes the glycemic index and multiples that amount of carbohydrates then divides it by 100 B. Can better predict blood sugar response C. More useful than glycemic index because it’s based on the serving Problems with high glycemic index/ load foods A. Very high glucose levels B. Chronically increased insulin levels C. Leads to high blood triglyceride levels and increased fat production D. A more rapid return of hunger after a meal, increased tendency for blood to clot Sweeteners A. Nutritive sweeteners- sugar, high fructose corn syrup, honey B. Sugar alcohol- sorbitol/xylitol which equals about 2.6 kcal/g and slows the metabolism to glucose C. High fructose corn syrup- made form corn, 55% fructose, cornstarch mixed with acid and enzymes, some glucose is converted to fructose, improved shelf-stability and food properties; Average American consumes 60 pounds a year D. Alternative sweeteners yield no kcal, but are there safety issues? 1. GRAS- extensive research has demonstrated the safety of the 5 low-calorie sweeteners currently approved for use in foods in the United States. 2. Equal- complaints of sensitivity such as headaches, dizziness, seizures, nausea, etc. 3. Acceptable daily intake is 50 mg per 1 kg of body weight, as stated by the FDA (14 cans of diet soda for average adult per day) 4. PKU NOTE: Artiﬁcial sweeteners are not associated with weight loss because they train us to enjoy sweet products which enhances our appetite for sweets. Resources https://www.google.com/url? sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjuseSjxOvKAhW E4CYKHZ5GBOUQjB0IBg&url=http%3A%2F%2Fwww.nutrientsreview.com%2Fcarbs %2Fdisaccharides.html&psig=AFQjCNG5HbPfYWf5dmHA5qv5122u5inLBw&ust=14551365612 19392 https://www.google.com/url? sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjZkOT4x- vKAhWIOiYKHdo1CqMQjB0IBg&url=http%3A%2F%2Fjama.jamanetwork.com%2Farticle.aspx %3Farticleid %3D1555133&psig=AFQjCNGDuWDb7PvXwSG_eU66fNLZ2yH4eA&ust=1455137550870037 https://www.google.com/url? sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwj- i_LVyOvKAhVIQiYKHYfuDzkQjB0IBg&url=http%3A%2F%2F2012books.lardbucket.org %2Fbooks%2Fan-introduction-to-nutrition%2Fs08-01-a-closer-look-at- carbohydrates.html&psig=AFQjCNENlY_AnweTPbgj9QOh9aUWP2v9rg&ust=14551377433718 50 https://www.google.com/url? sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjlybHzy- vKAhXDQCYKHR6vCmIQjB0IBg&url=https%3A%2F%2Fwhyevolutionistrue.wordpress.com %2F2015%2F10%2F19%2Fwas-darwin-lactose-intolerant %2F&psig=AFQjCNEMA6Cl_NPKLhfvUfcHgdPKu8P57A&ust=1455138557543099 https://www.google.com/url? sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiuiePqzOvKAhW B6CYKHV0KDbwQjB0IBg&url=http%3A%2F%2Fcnx.org%2Fcontents %2F9a926b86-67d0-4dbe-b5fe- d94581825886%403%2FChemical_Digestion_and_Absorpt&bvm=bv. 113943665,d.eWE&psig=AFQjCNH0WzU0Ov7UxRv0cGn32BOXNLBMkQ&ust=145513886120 5161
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'