4 classifications of carbohydrates 1) Monosaccharides 2) Disaccharides 3) Oligosaccharides 4) Polysaccharides Terms – mono-, di-, oligo- and polysaccharide, catabolism, ∙ Mono: Prefix meaning one; Includes simple carbohydrates (sugars). Chemically – all three monosaccharides are composed of carbon, hWe also discuss several other topics like anth 102 uiuc
Don't forget about the age old question of alma semock
We also discuss several other topics like What are some arguments that John O'Sullican uses in Annexation in the year 1845?
Don't forget about the age old question of What is meant by free will?
If you want to learn more check out What is used in Spectroscopy to determine the molecule's structure?
We also discuss several other topics like What is the definition of symbolic calculus?
ydrogen, and oxygen but arranged differently. Main monosaccharide found in foods is fructose. There are 3 types: 1) Fructose 2) Glucose 3) Galactose. Condensation reactions are used to attach / join / link the two monosaccharides together. ∙ Di: Prefix meaning two; Includes simple carbohydrates (sugars). Made up of 2 sugars including Maltose – two glucoses Sucrose – glucose and fructose Lactose – galactose and glucose Trehalose – two glucoses Isomaltose – two glucoses Formed during starch (amylopectin) digestion. Food sources (selected) Lactose Maltose – rare in foods, barley Mostly formed in the gi tract during starch digestion Sucrose – derived from sugar beets and sugar cane and found naturally in some fruits and vegetables Found in “table sugar” Added to many foods ∙ Oligo: Prefix meaning few or scanty; Includes complex carbohydrates. Contain 3 to ~10 monosaccharides and include Dextrins Limit dextrins Fiber. Oligosaccharides – contain 3 to ~10 sugars. Dextrin Is a bigger version of maltose made of 3 to 10 glucoses (in alpha 1-4 bonds) Can be digested Formed in the gi tract during starch digestion In some foods (selected) – found naturally in grains and grain products (barley, rice, corn, wheat) and some vegetables (such as potatoes)Also added to foods – breading, thickeners,… Limit Dextrins Consist of 3-10 glucoses linked together in both alpha 1-4 and alpha 1-6 bonds. Made in the body during (starch) amylopectin digestion Not found in foods ∙ Poly: Prefix meaning many; Includes complex carbohydrates. composed of 10 or more sugars (mostly glucoses) linked together. Examples Starch consists of amylose and amylopectin Storage form of glucose in plants Glucose molecules linked together in α1-6 and α1-4 bonds in amylopectin and α1-4 bonds in amylose Glycogen consists of glucoses Storage form of glucose in humans Glucose molecules linked together in α1-6 and α1-4 bonds Fiber ∙ Catabolism: Break down of glucose for energy in cells generates more CO2 than the catabolism of other nutrients 3 examples of monosaccharides, 4 examples of disaccharides and the sugars that make up the disaccharides ∙ 3 examples of monosaccharides include: 1) Fructose 2) Glucose 3) Galactose ∙ 4 examples of disaccharides and the sugars that make up the disaccharides include: 1) Maltose – two glucoses 2) Sucrose – glucose and fructose 3) Lactose – galactose and glucose 4) Trehalose – two glucoses 5) Isomaltose – two glucoses Formed during starch (amylopectin) digestion 3 examples of oligosaccharides ∙ Dextrins ∙ Limit dextrins ∙ Fiber 3 examples of polysaccharides 1) Starch consists of amylose and amylopectinStorage form of glucose in plants Glucose molecules linked together in α1-6 and α1-4 bonds in amylopectin and α1-4 bonds in amylose 2) Glycogen consists of glucoses Storage form of glucose in humans Glucose molecules linked together in α1-6 and α1-4 bonds 3) Fiber How many kcal per gram are supplied by carbohydrates ∙ 4 Which sugars are simple sugars and which are complex ∙ Simple: Monosaccharides and Disaccharides which include glucose, galactose, and fructose ∙ Complex: Oligosaccharides and Polysaccharides which include starch, glycogen, and fiber Food sources of monosaccharides and disaccharides ∙ Mono: Lesser amounts of glucose in foods. Glucose is most present in the body Galactose is only found in trace amounts in some foods (some fruits, some vegetables, and some cereals) Main monosaccharide found in foods is fructose. Fructose – sometimes called “fruit sugar” Fructose is found naturally primarily in. Fruits Also in some vegetables Also honey, agave, molasses, invert sugar*Lesser extent in grains Fructose may be added to foods as added sugars especially high fructose corn syrup. Fructose content in fruits in descending order – dates, raisins, figs, prunes, grapes, pears, apples, persimmons, blueberries, bananas, kiwi, watermelon, plums, honeydew melon, grapefruits, strawberries, blackberries, raspberries, oranges, pineapples, cantaloupes, peaches, nectarines, and apricots. Vegetables relatively rich in fructose – cabbage, cauliflower, eggplant, and sweet onions. Fructose ingestion > 75 g / day associated with diarrhea. Fructose ingestion by some in amounts over about 50 g / day may be associated with metabolic syndrome. Fructose ingestion in amounts providing > 20% kcal may ↑ LDL cholesterol ∙ Di: Lactose – primarily dairy products Sometimes called “milk sugar”. Lactose Maltose – rare in foods, barley Mostly formed in the gi tract during starch digestion Sucrose – derived from sugar beets and sugar cane and found naturally in some fruits and vegetables Found in “table sugar” Added to many foods Found in honey, maple syrup, white sugar (also called cane sugar), raw (also called turbinado) sugar, brown sugar, powdered sugar, sorghum syrup,….. Fruits (some) containing sucrose – papaya, dates, apricots, pineapple, nectarine, peach, cantaloupe, orange, honeydew melon, bananas, apples, plums, persimmons, and watermelon Candies are usually high in sucrose Vegetables with some sucrose – corn, peas, beets, sweet potato, onions, cabbage, artichoke, asparagus, okra, celery… Etiology of lactose intolerance, symptoms, diagnosis, and dietary recommendations ∙ Etiology – insufficient production of lactase which is the only enzyme that digests lactose in the digestive tract ∙ Symptoms – intestinal gas and/or cramps, sometimes diarrhea Occurs about 30 minutes to 2 hours after consuming a lactose-rich food(s) ∙ Diagnosis – Hydrogen (H2) Breath Test Ingest about 25 to 50 g lactose Monitor H2 gas in the breath (several hours) Gas production increases in breath if intolerant Bacteria are utilizing the undigested lactose and producing H2 ∙ Dietary- Don’t eliminate dairy products if possible Most can consume without symptoms ~6 g lactose (1/2 cup milk) with other foods Try eating yogurt with active cultures or fermented milk productsBacteria in these foods breaks down some of the lactose Take digestive aids - “Lactaid” pills Swallow or chew up 1 to 2 pills as eat dairy Potential nutrient deficiencies if avoid dairy Riboflavin, vitamin D, and calcium Oligosaccharide - dextrin, what is it made of, how it is made in the body, is it found in foods ∙ A bigger version of maltose made of 3 to 10 glucoses (in alpha 1-4 bonds) ∙ Can be digested ∙ Formed in the gi tract during starch digestion ∙ In some foods (selected) – found naturally in grains and grain products (barley, rice, corn, wheat) and some vegetables (such as potatoes) ∙ Also added to foods – breading, thickeners,… Polysaccharides – characteristics of starch and glycogen – storage form where/ where each is found ∙ Starch consists of amylose and amylopectin ∙ Storage form of glucose in plants ∙ Glucose molecules linked together in α1-6 and α1-4 bonds in amylopectin and α1-4 bonds in amylose ∙ Glycogen consists of glucoses ∙ Storage form of glucose in humans ∙ Glucose molecules linked together in α1-6 and α1-4 bonds ∙ Glucose is stored in plants as starch ∙ Starch is found primarily in ∙ Grains and grain products, ∙ Some vegetables (potatoes, corn, peas, ….), ∙ Some fruits (such as bananas) ∙ Legumes - beans and lentils ∙ Glycogen is not found in foods ∙ Initially present in animals but is destroyed and thus not found in meats What sugars make up starch and glycogen? ∙ Starch: consists of amylose and amylopectin Storage form of glucose in plants Glucose molecules linked together in α1-6 and α1-4 bonds in amylopectin and α1-4 bonds in amylose ∙ Glycogen: consists of glucoses Storage form of glucose in humans Glucose molecules linked together in α1-6 and α1-4 bonds Differences in structure between amylose and amylopectin and glycogen ∙ Glucose molecules linked together in α1-6 and α1-4 bonds in amylopectin and α1-4 bonds in amylose ∙ Glucose molecules linked together in α1-6 and α1-4 bonds in glycogen Examples of food sources of refined versus unrefined carbohydrates ∙ Refined carbohydrate sources Processed foods such as potato chips, corn flakes, white bread, white rice, applesauce, “fruit” in yogurt, candy… Soft drinks / sodas refined carbohydrate sources contain mostly added sugars or cornstarch (and are devoid of many nutrients originally present) ∙ Unrefined carbohydrate sources: Whole grains Legumes/beans/lentilsNuts and seeds Vegetables Fruits Milk Whole grains include the bran, germ and endosperm. The bran section is high in fiber and germ is high in fiber, healthy fatty acids, protein, and vitamin E AMDR for carbohydrates and is there an RDA for carbohydrates ∙ AMDR: 45%-65% of energy ∙ RDA: 130gm/day. Athletes may need 5-9g carbs per kg body wt What % of energy should come from added sugars? ∙ Added sugars should provide no more than 25% of day’s total energy Recommendations for whole grain consumption ∙ At least 50% should be whole grains Parts of the grain plant used to make whole grain products versus refined grain products ∙ White bread / refined products only contains endosperm not bran and germ ∙ Whole grains contain much of the Germ and Bran as well as the Endosperm What sugars are listed and not listed on food labels ∙ 18 g no %DV given ∙ The sugars listed include only the monosaccharides and disaccharides (i.e. simple sugars) ∙ The sugars listed do not distinguish between what is added versus naturally occurring ∙ Can look at ingredient list as a clue ∙ There is no Daily Value for sugars Carbohydrate Digestion –know all enzymes needed, what do the enzymes hydrolyze (which bonds) and in which carbohydrates, and where are the enzymes that digest carbohydrates found – see all underlined notes very carefully ∙ Small intestine -primary site for carbohydrate digestion ∙ Pancreatic amylase (released from the pancreas into the duodenum) hydrolyzes alpha 1-4 bonds in ∙ amylose (starch) – producing dextrin, dextrin producing maltose amylopectin (starch) producing dextrin and limit dextrin ∙ Limit dextrin contains multiple glucoses linked with some alpha 1-6 bonds and some alpha 1- 4 bonds ∙ Small intestine ∙ Isomaltase / also called alpha dextrinase (released from the intestine) – hydrolyzes alpha 1-6 bonds in ∙1limit dextrin producing maltose and isomaltose ∙ Isomaltose has 2 glucoses linked in alpha 1-6 bond ∙2isomaltose producing glucoses What are the end products of carbohydrate digestion and where are they produced o The “end products” of digestion are the sugars present in the small intestine after “digestion is finished” and include: Glucose, Galactose, Fructose How and where do the end products of digestion get absorbed into the body? o Once digestion is completed, these monosaccharides get into the intestinal cells by a process called absorptionName 2 types of absorption used for carbohydrates and what is required for each o1 Active transport – requires a carrier protein and energy- Glucose, Galactose o2 Facilitated diffusion – requires a carrier protein (no energy)- Fructose What happens to galactose and fructose after absorption – where do they go and what do they get converted into o Glucose, galactose and fructose o Enter the blood from the intestinal cells and travel to the liver via the portal vein o Carried across liver cell membrane into hepatic (liver) cells by transport proteins o Liver converts (metabolizes) galactose and fructose into glucose-related compounds through a series of biochemical reactions o Galactose and fructose are not typically found in the body except in the liver o Glucose is the main monosaccharide in body Name 3 main uses (roles) of glucose in the body o Energy, storage, maintenance of normal glucose concentration (blood glucose homeostasis) What happens to the glucose structure during catabolism for energy production – what biochemical reactions occurs, what are names of the cycles / reactions, initial substrates and end products o1Energy o Catabolized (broken down) through several biochemical reactions to produce energy o Energy is available in the body in the form of ATP (adenosine triphosphate) o Some biochemical reactions generating energy from glucose include: glycolysis followed by the conversion of pyruvate to acetyl CoA, followed by the citric acid, or called the Krebs, cycle o Glycolysis: Glucose (6 carbons) is broken down into two Pyruvate (3 carbons each), Glucose is the initial substrate (beginning glycolysis)---- Pyruvate is the end product of the glycolysis Name two “storage” compounds that are made in the body from glucose o Glycogen & fat Where is glycogen made and stored and under what conditions o Liver & muscles o Stored in the form of glucose (carbs) in the body When is glycogen broken down and under what conditions o When more glucose is needed o Glycogen is made when the body has an abundance of extra available glucose that is not needed for energy production o Glycogen can be broken back down into glucose (Process is called glycogenolysis) o Only glucose released from glycogen in the liver can enter the blood o Glycogen broken down in the muscles can not be released as glucose into the blood What tissue contains glycogen that is able to be released as glucose into the blood o liver Where is fat (triglycerides) made and stored and under what conditions o Process is called lipogenesis and occurs primarily in the liver o Occurs when o1glycogen stores are “full” in the liver and muscles and o2when the body has enough glucose available for energy (ATP) productionIf fat is broken down what is generated and what is not generated o Fat cannot be converted to glucose Under what conditions does muscle mass breakdown and do the amino acids get converted to glucose o If glucose is not available then the body will break down protein (including muscle) and use its amino acids to make glucose o The reaction series in which amino acids are converted into glucose is called gluconeogenesis Biochemical pathways- energy production from glucose What happens in glycolysis? What starts the pathway, what is the end product, is energy produced? o Glycolysis o Glucose (6 carbons) is broken down into two Pyruvate (3 carbons each) o Glucose is the initial substrate (beginning glycolysis) o Pyruvate is the end product of the glycolysis o Some energy is generated during selected steps as electrons are sent to the electron transport chain o Energy (ATP) is generated through a series of phosphorylation reactions called electron transport chains What is the name of the set of reactions in which energy is produced? o Electron transport chain What happens to pyruvate after it is made? o Acetyl CoA What compound is used to make glycogen? And what is the name of the set of reactions used to produce glycogen? o Glucose is converted to glycogen o glycogenesis Under what conditions is glucose turned into fat? o1glycogen stores are “full” in the liver and muscles and o2when the body has enough glucose available for energy (ATP) production What is the name of the biochemical pathway in which glucose is made from amino acids? When is this likely to occur? o Gluconeogenesis o Occurs because glucose is mandatory for some body cells and the body must maintain blood glucose in the normal range What 2 hormones are involved in the maintenance of normal blood glucose (i.e. homeostasis?) o Glucagon, insulin How do each of these hormones affect blood glucose concentrations? o1Glucagon (hormone from pancreas) Helps raise blood glucose if it is too low Stimulates the breakdown of glycogen in the liver to glucose which gets released into the blood If needed amino acids can also be converted to glucose Fats cannot be converted to glucose o2Insulin (hormone from pancreas) Helps lower blood glucose if it is too high Stimulates the uptake of glucose into insulin-dependent cells* such as muscle cells, heart, fat cells, … Insulin binds to membrane receptor (see next slide) Insulin stimulates glucose transporters to move to cell membrane to pick up the glucose and bring it across the cell membrane and into the cell What are sources of glucose for the blood? o Foods consumed provide carbohydrates which are digested, absorbed and directly supply (or are converted into) glucose o Glycogen stores in the liver only (not the muscle) can be broken down (catabolized) to release glucose into the blood o Amino acids from the breakdown of protein (muscle mass) – not routinely done What happens to amino acids from muscle catabolism during fasting and with consumption of low carbohydrate diets? o Prolonged fasting situations and low carbohydrate diets (low = typically < 50 g) o Cause the body to break down (catabolize) muscle protein (also called lean body mass) so its amino acids can be converted into glucose (process is gluconeogenesis) o Occurs because glucose is mandatory for some body cells and the body must maintain blood glucose in the normal range o Depleted liver glycogen store When and how do ketones form in the body including what is not present in the cells that leads to ketone formation o Ketones are made as fats are being broken down for energy if there is not enough glucose in the cell What happens to the blood when ketones levels rise? o Low level acidosis Fiber- polysaccharide, nondigestible CHO and lignin that are intact and intrinsic in plants Name the benefits of consuming water soluble viscous fibers and of consuming water insoluble fibers o everyone but especially those with diabetes and with high blood cholesterol o Delay* gastric emptying to slow down absorption o Slow down** intestinal nutrient absorption o Lesser benefit in helping to improve constipation What happens to transit time when you delay (slow down) gastric emptying o transit time in GI tract is longer What do some bacteria produce when they ferment fibers and what is the benefit of these SCFA substances o Short chain fatty acids o SCFA provide energy to cells in colon o SCFA lower pH of colon to inhibit growth of less desirable bacteria and favor the growth of healthier bacteria (lactobacillus and bifidobacteria) (prebiotic role) Remember the definition of prebiotic What is the usual range of acceptable fiber intake? o DRI Age 19 to 50 yrs Age > 51 yrs o Men 38 g 31 g o Women 25 g 21 g o Usual recommendation 20 to 30 g per day o Usual intake <15 gWhat percent of grains in the diet should be as whole grains? o 50% What foods contain fiber – which food group is highest? o Whole grains - at least half of daily grains or at least 3 oz as whole grains o Fruits o Vegetables o Legumes / beans and lentils o Nuts and seeds What can happen if too much fiber is consumed? o May cause gi tract problems – gas, bloating / abdominal distention, diarrhea or constipation o “Beano” – contains enzymes to help digest galacto-oligosaccharides and decrease bacterial gas formation What happens if foods with a high glycemic index are consumed? o Raise blood glucose How is the glycemic index of foods determined? o High GI foods have a value of > 70 o Low GI foods have a value < 55 What is the size of the stomach in someone who has had Gastric Bypass (GBP) Surgery? o 30 ML What is done with Billroth I and II procedures o Billroth I and II – involve resection of the stomach (50 to 75%) and anastomoses with intestine (duodenum or jejunum) o Used with gastric ulcer and cancer What conditions cause dumping syndrome? o1Dumping syndrome – due to the emptying of gastric contents that are hyperosmolar into the small intestine o Causes a vascular fluid shift which may o ↓ circulatory volume and ↓ blood pressure o Causes nausea, abdominal cramps, weakness, diaphoresis, diarrhea, hypoglycemic reaction, … o Is precipitated by the consumption of carbohydrates, especially simple sugars Name 2 dietary changes needed to treat dumping syndrome o Lower CHO intake to ~40% - 50% kcal o Severely limit mono- and disaccharide intakes o Consume foods with no added sugars o Distribute carbohydrates among meals o Don’t eat carbohydrate rich meals What is a bezoar (phytobezoar), why does it form, and what does a person need to know to decrease the risk of bezoars o2Bezoar formation – “concretions” of “undigested materials” resulting from ↓ gastric functions associated with gastric resection (usually Billroth I and II) o Plant fiber (phytobezoar) mostly derived from orange/citrus, berries, green beans, apples, other o Others - hair, string, textile fiber (trichobezoar) and from gum and some medications o Treatment - inject (via endoscopy) enzymes (cellulase, pancreatic enzymes, papain,..) directly into the bezoar to try to break it up or surgical bezoar removalo Diet – reduce intake of food associated with bezoars Why carbohydrate restriction sometimes is needed with respiratory failure: o Rationale: catabolism (break down) of glucose for energy in cells generates more CO2 than the catabolism of other nutrients o Carbon dioxide (CO2) must be exhaled by the lungs and increases the work of the lungs o When trying to wean a patient from the ventilator want to try to minimize extra work by the lungs o Diet (tube feeding) is typically higher in fat and protein and lower in carbohydrates Diabetes – descriptions, which type is more prevalent - type 1 or type 2, is obesity associated more with type 1 or type 2 o 1. No production of insulin (absolute insulin deficiency) – type 1 --- 5-10% of cases o 2. Inadequate release (secretion) of insulin – type 2 --- 90-95% of cases (MOSTLY OBESE PEOPLE) and / or o 3. Inadequate utilization of insulin or tissue response to insulin at 1 or more points in a complex pathway of hormone action (called insulin resistance) – type 2 Descriptions of impaired fasting glucose and impaired glucose tolerance including blood glucose concentrations (FBG) o Impaired Fasting Glucose (IFG) – Prediabetes o Blood glucose concentrations are greater than normal but not high enough to be diagnostic of diabetes o IFG FBG 100 to 125 mg/dL o Normal FBG < 100 mg/dL o FBG Diabetes > 126 mg/dL 4 chronic complications of diabetes – what organs affected o Chronic – associated with poorly controlled blood glucose concentrations o Heart disease (premature) o Nephropathy – kidneys fail o Neuropathy o Lose “feelings” in extremities o Gastroparesis o Retinopathy – blindness Primary goal in treating diabetes and how it is achieved (diet, exercise, monitoring, medications) o Primary goal - keep blood glucose concentrations in near normal range through o Medications o Insulin (type 1 and some with type 2) o Other – three main mechanisms (type 2) o Diet modifications o Self blood glucose monitoring o Exercise What types of protein foods and sources of fat are recommended for those with diabetes and why o Dietary Protein and Fat (types 1 and 2 and prediabetes) o Promote consumption of protein sources that are low in fat, especially saturated and trans fats, and low in cholesterol o Promote consumption of protein sources rich in omega 3 fatty acids such as salmon What types of modifications in carbohydrates are made for someone with diabetes – types 1 and 2 o Carbohydrate Type 1 - amount CHO consumed needs to be coordinated with insulin administration and dose and blood glucose concentration Distribution of carbohydrates among meals - don’t eat low carbohydrate and then high carbohydrate meals Emphasize foods rich in soluble fiber Don’t eat foods with a high glycemic index alone o Carbohydrate (CHO) Type 2* and prediabetes* – control amount CHO consumed and eaten in fairly consistent manner No coordination needed with oral medications Emphasize soluble, viscous fiber rich foods Avoid eating foods with a high glycemic index alone 2 approaches in teaching patients about carbohydrates o1Exchange system Each meal allows for a specific number of exchanges for each of the food groups Example breakfast can have 2 starch exchanges, 1 milk exchange, 1 fruit exchange, 2 meat exchanges and 1 fat Person selects foods and quantity from within each exchange group o2Carbohydrate counting Teach what foods contain CHO and how to read food labels for g CHO per serving and serving sizes How to calculate g CHO for portions larger or smaller than listed serving size Can also teach carbohydrate to insulin ratios