FSHN 150 1st Edition Lecture 8Outline of Last LectureI. CarbohydratesOutline of Current LectureII. Digestion and AbsorptionIII. Functions of CarbohydratesIV. Blood Glucose V. Food sources of CarbohydratesCurrent LectureCarbohydrates: Digestion, Absorption and RegulationI. Digestion and absorptioni. Cooking softens the connective fibrous tissues ii. Mouth: salivary amylase in spit breaks down starchiii. Stomach: deactivates salivary amylaseiv. Small intestine: breaks down disaccharides(sucrose, lactose, maltose) intomonosaccharides(glucose, fructose, galactose)v. Absorption: in small intestines, brought to liverGlucose and galacatose(active transport)Fructose (facilitated diffusion)vi. Portal vein to liverII. Functions of Carbohydratesi. Energy yielding: glucose-from glycogen= 12 hour supply of glucoseii. Protein sparing- from protein (muscles)= glucose undesirableiii.Prevent ketosis- lack of carbs to completely metabolize fatty acid breakdowniv. SweetenerIII. Regulation of blood glucose to preventi. Hyperglycemia-high blood glucose a. Body uses insulinii. Hypoglycemia- low blood sugara. Body uses glucagonIII. Organs and hormones in blood glucose controli. Maintains homeostasisii. Role of liver- regulates glucose that enters bloodstreamiii. Role of pancreas- releases insulin and glucagonIV. The function of:i. Insulin a. Promotes glycogen synthesisb. Increased glucose uptake by the cellsc. Reduced gluconeogesisd. Net effects= decrease blood glucoseii. Glucagon a. Breakdown of glycogenb. Enhances gluconeogesisc. Net effects= raises blood glucoseV. Food sources of carbohydratesi. Bananas have complex and simple carbohydratesii. Fat free milk has only simple carbohydratesiii. Apples have both, but if turned into juice they loose their complex carbsVI. Currently the top 5 carbs sources for US adults for US adults1) White bread2) Soft drinks3) Cookies and cakes (including doughnuts)4) Sugars/ syrups/ jams5) Potatoes (only complex carbohydrate on list)VII. Whole and refined grainsi. Grains, seeds, or kernels contain 3 parts; endosperm, bran, and germii. Processed grains need enrichment= adding some of the vitamins back VIII. High Carb Diet (complex carbs)i. Rich in fiber, vitamins and minerals, phytochemicals and antioxidantsii. Contains essential fatty acidsiii. Promotes satietyIX. Recommended for Simple Sugars intakei. Low nutrient density, should be no more than 10-15% of total kcals/daya. 50g (10 tsp)= 200 kcalsii. Average US intake: 18% of total intake a. 82g (16 tsp)= 328 kcals WAY TOO HIGHiii. Extra calories come from added sugars to foods and beverages during