Exam 2 Review- Nutrition Science.docx

Sarah Crissman Carbohydrates ● What are carbohydrates made of? ○ Carbon, hydrogen, and oxygen ● Where can carbohydrates be found? ○ Abundant in grains and other plants ○ Found in milk and dairy products ● What is the difference between whole grains, refined grains, and enriched grains? ○ Whole grains contains all three parts, the bran, the germ, and the endosperm. ○ Refined grains take out the bran and the germ. ○ Enriched grains are refined grains with vitamins added back in, folic acid, thiamin, riboflavin, niacin, and iron ● What are the three components of Whole grains? ○ Bran, endosperm, germ ● What are the cons of consuming bread? ○ Could be hard to digest without proper soaking, sprouting or traditional processes ○ Could contain gums and preservatives that irritate the GI, ○ May increase risk of inflammation, gluten intolerance or allergy, ○ Bread is typically high in sodium ● What are the two main functions of carbohydrates in food and the four functions in the body? ○ Functions in food: Source of fiber and add sweetness and flavor ○ Functions in the body: source of energy for all of the cells in the body, source of energy for the brain, regulate intestinal health, reduce the use of protein of energy ● Classifications of Dietary Carbohydrates and their Chemical Composition: ○ Monosaccharides: sugars that are made up of one sugar unit ■ Glucose, fructose, galactose ○ Disaccharides: sugars made of two sugar units ■ Sucrose, lactose, maltose, raffinose ○ Oligosaccharides: units are absorbed by cells of the intestine and dumped into the blood for all body cells to pick up and use for energy ■ Sucrose, lactose, maltose, raffinose ○ Polysaccharides: (more than 10 sugar units) chains (or polymers) of more than one monosaccharide

■ Starch, glycogen, cellulose, fibers ● What is glycogen? When is glycogen used?

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○ Storage form of carbohydrates in animals, consists of many glucose molecules (liver and muscle) ○ Glycogen is used for energy for exercise (intense weightlifting) Non Nutritive sweeteners: Sweetness level and their chemical name… ○ Equal- aspartame, sweetness level 200 times sweeter than sugar. ○ Splenda- sucralose, sweetness level 600 times sweeter than sugar ○ Sweet n' low- saccharin, sweetness level 300-400 times sweeter than sugar Sugar alcohols: ○ Mannitol: Laxative effects when recommended intake is exceeded ○ Erythritol: Best sweetener from sugar alcohols with minimum negative effects, lowest in calories and net carbs has no effect on blood sugar How are cavities caused? Which carbohydrate is responsible? ○ Cavities are caused by the progression of tooth enamel and ultimately the tooth itself, through the action of bacteria on carbohydrates in the mouth ○ Sucrose is the main carbohydrate responsible Dietary Fiber ○ Soluble- type of fiber that dissolves in water and often forms of viscous gel that acts to slow digestion and lower blood cholesterol and the risk of heart disease, they are also often readily fermented by bacteria in the colon ○ Insoluble- a type of fiber that does not dissolve in water, increases transit time through the GI tract, and contributes "bulk" to stool, fostering regular bowel movements ○ Resistant Starch- starch that remains intact after cooking, in not broken down by human digestive enzymes, and is not absorbed from the intestines. Can be turned into short chain fatty acids by intestinal bacteria. ○ Functional Fiber- non digestible carbohydrates is isolated from plants and animals and added to foods, which have a beneficial effect on health, such as a psyllium and pectin Carbohydrate Digestion: which enzyme is active in each site / what is being broken down ○ Mouth- salivary amylase breaks them down into shorter polysaccharides chains ○ Stomach- salivary amylase is inactivated by gastric acid and starch digestion stops

○ Small intestine- pancreatic amylase continues, starch digestion, breaking it down to maltose and oligosaccharides ○ Microvilli- the enzymes that break down sucrose, maltose and lactose in the microvilli ● What are you left with to be transported out of the cells and into the blood? ■ The resulting monosaccharide are absorbed by the small intestine and are then transported out of the cells into the blood. ● According to the Dietary Guidelines, what percentage of you total grain intake be whole grains? ○ 50%

● What is the difference between type 1 and type 2 diabetes? ○ Type 1- an autoimmune disease characterized by elevated blood glucose

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levels, caused by destruction of the cells in the pancreas that normally produce insulin ○ Type 2- condition characterized by elevated blood sugar levels due to insulin sensitivity or resistance and some impairment of insulin secretion from the pancreas What is insulin and where is it produced? ○ Hormone that is produced in the pancreas that removes glucose from the bloodstream for use by the cells. Produced in pancreas Insulin signals which cells to take up glucose? ○ Skeletal muscle and adipose tissue Insulin promotes the storage of excess glucose as what? ○ Glycogen When is glucose converted into fat? ○ Glucose converted into fat if there is too much glycogen in the body. Converted in the liver and stored as adipose tissue What is glucagon and where is it produced? ○ A hormone that is produced in the pancreas that increases glucose availability in the blood in response to blood glucose While insulin is responsible for signaling cells to take up glucose, glucagon is responsible for signaling the liver to do what two things? ○ Signals the liver to release glucose by breaking down glycogen as well as making new glucose molecules Can the brain use fatty acids for fuel? ○ The brain cannot use fatty acids for fuel, so it converts fatty acids to ketone bodies How are ketones formed and when are they used for energy? ○ Compounds synthesized from fatty acids to ketone bodies

● What is the difference between ketosis and ketoacidosis? ○ Ketosis- low level of ketones in the blood, normal process of the body,

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safe function of a low-carb ketogenic diet. ○ Ketoacidosis- extremely high level of ketones in blood, can turn the blood acidic, deadly if untreated, occurs in diabetics who don't take enough insulin or aren't well, people who are starving or alcoholics Hyperglycemia vs Hypoglycemia? ○ Hyperglycemia- higher than normal blood glucose levels (fasting plasma) glucose > 100mg/dl ○ Hypoglycemia- abnormally low blood glucose levels, resulting in symptoms of anxiety, hunger, sweating, and heart palpitations. (fasting plasma glucose < 70 mg/dl Treatment for Type 1 and Type 2 Diabetes? ○ Treatment 1- administering insulin. (injection, pump) ○ Treatment 2- change your diet, eat well, exercise, control sleep, manage stress insulin (exogenous) Hemoglobin A1C and Fasting Plasma Glucose Test levels for normal, prediabetic and diabetic? ○ Normal Hemoglobin A1C and fasting plasma glucose levels- 1Cabout 5%; fasting plasma glucose- 99 or below (mg/dL) ○ Prediabetic Hemoglobin A1C and fasting plasma glucose levelsA1C- 5.7 to 6.4%; plasma fasting- 100-125 mg/dL) Glycemic Index vs Glycemic Load. Just know the difference, why it may not be reliable and what factors influence this number. ○ Glycemic index- how drastically raises glucose levels ○ Glycemic load- extent of increase in blood glucose levels What is the main result of Epinephrine release? ○ Adrenaline, a hormone released from adrenal glands to help the body to prepare for fight-or-flight response by increasing glucose availability in the blood. ○ Increases blood glucose levels Four Stages Of Glucose Metabolism: ○ Brain’s source of fuel ■ Absorptive- Glucose ■ Postabsorptive- Glucose ■ Fasting- Glucose + Ketone Bodies ■ Starvation- Ketone bodies Activity of glucose, insulin, glycogen, glucagon

○ Blood glucose is high signaling the pancreas to release insulin to help the glucose get Into the cell. Insulin also promotes the storage of excess glucose as glycogen

LIPIDS

● What is Dietary Fat? ○ A compound in plant and animal foods that serves as an important energy

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source and among other functions is necessary for absorption and transport of fat soluble vitamins Fat soluble vitamins ○ A, D, E, K What are Lipids? ○ Structurally diverse group of naturally occurring molecules that are generally insoluble in water, but are solvents, examples include fatty acids, triglycerides, sterols, and phospholipids 3 Main Parts Of A Fatty Acid ○ fatty acid ○ carboxyl group ○ methyl group Saturated vs Unsaturated Fats ○ Saturated- a fatty acid that contains no double bonds ○ Unsaturated Fats- a fatty acid that has one or more double bonds Unsaturated Fats: ○ Monounsaturated- a fatty acid with only one double bond ○ Polyunsaturated- a fatty acid with two or more double bonds Triglycerides: ○ Glycerol- a three carbon compound that makes up the backbone of a triglyceride molecule ○ Fatty Acid- a chain of carbon atoms with hydrogen atoms Triglycerides vs Cholesterol ○ Cholesterol is used by the body to produce hormones and cell components such as the membranes of cells ○ Triglycerides is used primarily used as a storage form of energy Sterols ○ Precursor for steroid hormones ○ Cell membrane production

● Types of Sterols ○ Cholesterol a sterol that is produced by the body and required for steroid production and cell membrane ● Two main sources of cholesterol ○ Phospholipid molecule that is both hydrophobic (water fearing) and hydrophilic (water loving) and is required to form cell membranes: lecithin, which can be found in egg yolks, liver, and some plant products, is a phospholipid ● Phospholipid ○ Lecithin- the most abundant phospholipid in the body: frequently added to food products like salad dressings as an emulsifier

● What is emulsification? Which lipids play a role in emulsification? ○ A process that allows lipids-fats- to mix with water. Micelles are lipid ●

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molecules that play a role in emulsification Which enzyme is responsible for breaking down triglycerides? How does it do this? ○ Lipase removes fatty acids from glycerol backbone What is a chylomicron? ○ Very large lipoprotein that transports triglycerides and other dietary lipids away from the small intestine, then into the bloodstream and then in the blood for circulation Three Types Of Lipoproteins ○ Very Low-Density Lipoprotein (VLDL) a lipoprotein responsible for transporting primarily triglycerides to adipose tissue, cardiac muscle, and skeletal muscles ○ Low density Lipoprotein (LDL)- a lipoprotein responsible for transporting primarily cholesterol from the liver through the bloodstream to the tissues ○ High-Density Lipoprotein (HDL)- a lipoprotein responsible for transporting cholesterol from the bloodstream and tissues back to the liver What Are Chylomicrons Responsible For? ○ Transporting fats that we have absorbed and deliver to body tissues How Do The Fats From The Diet Arrive In The Small Intestine? ○ Fats arrive as lipid droplets, which are digested and emulsified into micelles, which are absorbed into the intestinal cells as monoglycerides, fat, cholesterol, and apoproteins How Is The Chylomicron Formed?! ○ Chylomicrons are formed in the absorptive cells of the small intestine after fat absorption and travel through the lymphatic system to the bloodstream

● Chylomicrons Deliver Fatty Acids & Cholesterol To Muscle & Fat Tissues To Be Used For Energy, The Remaining Is Transported Where? ○ Liver ● What Are The Two Types Of Lipoproteins that Liver Forms? ○ empty HDL and VLDL ● What Are The Two Main Fates Of Fatty Acids From VLDL? ○ Energy or storage ● Lipase Changes VLDL Into? ○ Intermediate Density Lipoprotein (IDL) or fatty acids ● LDL Has More _____ Than Any Other Lipoprotein? ○ Cholesterol ● Why Do Tissues Need Cholesterol? (2 reasons) ○ Hormones and maintaining cell membrane ● What Happens After LDL Gives tissues cholesterol? ○ LDL returns back to the liver by binding onto receptors, and recycling to make more lipoproteins or excreting in bile ● How are these two MCTs digested differently, C8 (Caprylic acid) and C12 (Lauric acid)? ○ C8- acts as a ketogenic oil meaning it bypasses the digestive tract and goes straight to the liver, where it is converted into fat burning ketones. Ketone energy production ○ C12- behaves more like a typical fatty acid- it first goes through your stomach, where the small intestine breaks it down, your blood then absorbs it before your body turns it into energy ● The Omega 3 Pathway: ○ ALA - EPA- DHA ■ ALA- found 18 carbon omega- 3 fatty acid that can be produced in the body or by the diet. Sources- chia seed, flaxseed, flax oil. (short chain) ■ EPA- a 20- carbon omega- 3 fatty acid that can be produced in the body by the metabolism of alpha- linolenic acid or provided in the diet. Sources- fatty fishes such as salmon, marine plankton, fish oil supplement (long chain) ■ DHA- 2 carbon omega- 3 fatty acid that can be produced in the body from alpha-linoleic or absorbed by the diet. Sources- fatty fish, eggs, fortified foods (long chain) ● Linoleic Acid VS Linolenic acid, what’s the difference? ○ Linoleic- double bond at 6th carbon molecule ○ Linolenic- double bond at the 3rd carbon molecule ● Hydrogenation

○ Chemical process by which hydrogen molecules are added to unsaturated ●

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fatty acids Trans Fatty Acids ○ fatty acids creating by adding hydrogen to liquid vegetable oils (partial hydrogenation) to make them more solid How do trans fats negatively affect health? ○ Trans fats raise your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels ○ increases your risk of developing heart disease and stroke ○ higher risk of developing type 2 diabetes. What Type of Disease is Cardiovascular? ○ Group of conditions that impair the heart and blood vessels (veins and arteries as well How do the LDL’s harm the blood vessel? ○ Elevated levels of cholesterol-rich low density Lipoproteins (Ldls) in the blood What is plaque, and how does it develop? ○ Waxy accumulation of cholesterol and triglycerides within the arterial wall. ○ Can develop due to smoking How does a heart attack occur? ○ Blocked blood flow in the coronary How does a stroke occur? ○ Clot impairs that supply of blood to the brain 5 risk factors associated with metabolic syndrome ○ Low HDL cholesterol ○ Visceral obesity ○ Insulin resistance ○ Hypertension ○ High triglycerides