Chapter 7 Explain the origin of dietary carbohydrates Categorize the different carbohydrates as either mono di or polysaccharides Monosaccharaides one sugar Fructose glucose galactose Disaccharides two sugars Sucrose glucose and fructose Maltose glucose and galactose Lactose Galatose and glucose Polysaccharides long chains of monosaccharides chained together 1 Starch straight or branched chains of glucose like rice pasta bread and potatoes 2 Fiber not digestable but important no ezyme to digest Some foods can be both dietary and functional ex pectin to yogurt texture and in Dietary fiber found naturally in foods Functional fiber Added to food for digestive benefit Psyllium added to cereal Dietary and Functional total fiber you eat citrus fruits Soluable fiber dissolves in water viscous Can have thickening properties Fermented in large intestine by bacteria Insoluable fiber doesn t dissolve in water branflakes Less readily fermented by bacteria Fiber and solubility are not exact effects Soluable fiber generally moves slower through tract and can have laxative effect in absorbing H20 Insoluable fiber generally moves rather fast Humans store limited amounts important source of glucose Can t access glycogen in meat and poultry breaks down when animal die Identify carbohydrate storage both in plants and animals Animals store carbohydrates as glycogen in the liver and muscles Plants store them as starch Amylose is a straight chain and amylopectin is a branched chain Explain the dietary differences between whole and enriched grains 3 parts of single kernel of grain Bran outer shell rich in fiber B vitamins phytochems minerals Chromium and zinc Germ seed nutritional powerhouse Vitamin E heart healthy fats phytochemicals B vitamins Endosperm starchy part Protein B vitamins some fiber not as much as bran Enriched grains attempt to restore some of the nutrients lost in refinement by adding back folic acid thiamin niacin riboflavin and iron Improves nutritional quality fiber still lost Whole grains whole wheat brown rice oatmeal Contain all three parts of kernel 3 servings daily recommended It may reduce risk of heart disease stroke and diabetes Describe lactose intolerance People without enzyme lactase cannot digest lactose Lactose maldigestion natural part of aging process It is the inability to absorb the milk sugar lactose properly due to a decrease in the amount of the enzyme lactase in your digestive tract 25 americams and 75 of aduls wordlide do not digest lactose well Europe central Africa Middle East are less likely to have it Dairy products provide over 70 calcium needed Lactose intolerance severe lactose deficiency Undigested lactose draws water into digestive tract causing diarrhea Bacteria ferment lactose to produce gases Bloating gas cramps Not the same as milk allergy Some dairy foods better tolerated Whole easier than skim Hard aged cheeses easier Yogurt better Describe carbohydrate digestion where chemical digestion begins and is completed Chemical digestion of carbohydrates begin in the mouth Salivary amylase intakes hydrolysis in the mouth Breaks down starch into maltose disaccharide no carbohydrate digestion in stomach Hydrochloric acid in stomach destroys salivary amylase Chemical digestion mostly occurs in the small intestine Pancreatic amylase is produced in the pancreas and secreted into small with the enzyme salivary amylase during a hydrolysis Breaks starch down to maltose in the small intestine Disaccharides to monosaccharide Disaccharide digestion Intestinal cells make disaccharides enzymes sucrose lactase maltase Disaccharides digestion takes place on surface of brush board of small intestine Hydrolyzed into monosaccharide Which are transported into enterocytes Identify the two hormones that control blood glucose and describe their function and origin Insulin released by pancreas to lower blood glucose level Directs glucose into cells and determines whether it will be used immediately as energy or stored for later use If amount of glucose in blood exceeds body s immediate energy needs insulin directs it to be stored as glycogen When glucose storage reaches limit it stores as fat Glycogen storage in muscles and liver Glucagon used when blood glucose levels dip too low It directs release of glucose from stored glycogen in liver Glucagon signals liver to start manufacturing glucose from noncarbohydrate sources protein Proteins have amino aids to generate glucose Epinephrine acts on liver and muscle cells to slow breakdown of glucose Released from stress and low glucose levels Explain the consequences of not getting enough carbohydrates in the diet Fasting after 18 hours glycogen stores depleted In burning fat without glucose ketone bodies released which make blood acidic Ketosis after 2 day fast Protein breakdown from muscles and organs for glucose Protein levels dangerously low Chapter 8 Explain the difference between natural and added sugar Natural sugars nutrient dense lots of fruit Fruit can contain more than 15 sugar by weight It satisfies urge for sweetness and makes you full Fruit also contains fiber and H20 Difficult to over consume calories from fruits and vegetables Added sugars can lower HDL levels Empty calories Honey and fructose not nutritionally superior to sucrose 1 source added sugars in US sweetened soft drinks Recommended no more than 25 of total calories by DRI Who recommends less than 10 30 tsp added sugar daily in USA Identify the aliases of sugar on food labels Corn sweetener corn syrup dextrose sucrose brown sugar fructose lactose honey syrup high fructose corn syrup fruit juice concentrate invert sugar raw sugar malt syrup maltose molasses Explain where most of the sugar in the diets of Americans comes from 33 soft drinks Over 15 sugars candy 12 13 cakes cookies pies 9 fuitades lemondaes and fruit punch 6 grains cinnamon toast sweetened waffles Differentiate between the sugar substitutes Sugar substitutes as sweet or sweeter than sugar with less cals Must be FDA approved Polyols sugar alcohols Chem structure has added alcohol component Sorbitol mannitol Xylitol Naturally found in plants and produced in gum and candies May be sugar free but may not be calorie free Polyols completely unabsorbed in GI tract Saccharin pink Packet used in world wars Not metabolized in body No cals Was linked to bladder cancer but not anymore Aspartame Composed of 2 amino acids 4cal gram 200 time sweeter than sucrose Soft drinks Acceptable intake 50mg kg body