Nutrition: From Science to You Chapter 4 - Carbohydrates PDF

Nutrition: From Science to You Fourth Edition Chapter 4 Carbohydrates Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  & / I ...

Nutrition: From Science to You Fourth Edition Chapter 4 Carbohydrates Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  & / I  S What are Carbohydrates and How Are & They Classified? Produced by plants during photosynthesis, the process in which plants use the energy from the sun to create energy After eating plant foods, humans convert the Loading… carbohydrates into glucose. Glucose – Most abundant carbohydrate – Preferred source of energy for the body Carbohydrate-rich plant foods make up the foundation of diets all over the world. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Photosynthesis: How Glucose is Made Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Dietary Patterns of Selected Diets Loading… Willcox, D. C., Scapagnini, G., & Willcox, B. J. (2014). Healthy aging diets other than the Mediterranean: a focus on the Okinawan diet. Mechanisms of ageing and development, 136-137, 148–162. https://doi.org/10.1016/j.mad.2014.01.002 Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Classification of Carbohydrates Simple carbohydrates – Monosaccharides – Disaccharides – Perceived as sweeter than complex carbohydrates ▪ Mix with saliva and react with taste buds Complex Carbohydrates – Oligosaccharides – Polysaccharides ▪ Starch, Fiber, & Glycogen Carb video: https://www.youtube.com/watch? v=Q29F4a61J7k Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Monosaccharides Are Single Sugar Units (1 of 2) Monosaccharide = one unit of sugar Three nutritionally important monosaccharides – Glucose ▪ Most abundant monosaccharide in the body and foods ▪ Is the preferred and main source of energy for the brain and red blood cells Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Monosaccharides Are Single Sugar Units (2 of 2) – Fructose ▪ Sweetest of natural sugars ▪ Found abundantly in fruits ▪ Part of high-fructose corn syrup – Galactose ▪ Commonly occurs as part of the disaccharide lactose ▪ Rarely found on its own Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved The Structural Differences Among Glucose, Fructose, and Galactose Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Disaccharides Consist of Two Sugar Units Disaccharides are formed when two monosaccharides join together through a process called condensation. Three disaccharides – Sucrose (table sugar) ▪ Most common ▪ Found naturally in sugar cane and sugar beets – Lactose (milk sugar) ▪ Found in dairy products – Maltose ▪ Least common ▪ Formed from digestion of starches Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Condensation Reaction Links Monosaccharides to Form Disaccharides Loading… Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Oligosaccharides Have Fewer Sugar Units Oligosaccharides contain 3 to 10 monosaccharides. Similar to both monosaccharides and polysaccharides – Monosaccharides: Similar in length – Polysaccharides: Both make up cellulose in plant cell walls and, like fiber, both escape digestion Food sources: Legumes, beans, cabbage, brussels sprouts, and broccoli Found in human breast milk Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved The Structure of an Oligosaccharide Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Polysaccharides Consist of Many Sugar Units (1 of 4) Starch – Plants store glucose in chains of starch. ▪ Amylose: Straight chain of polysaccharides found in starch; – More resistant to digestion than amylopectin; resistant starch is not digested in the GI tract. May improve health of digestive tract May improve glucose tolerance May stimulate growth of beneficial intestinal bacteria (act as prebiotics) ▪ Amylopectin: Branched chains of polysaccharides found in starch – Easier to digest Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Comparison of Polysaccharides: Starch, Fiber, & Glycogen ↑ Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Polysaccharides Consist of Many Sugar Units (2 of 4) Fiber – Most forms are non digestible polysaccharides and occur naturally as a structural component called cellulose. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Polysaccharides Consist of Many Sugar Units (3 of 4) Fiber – Most plant foods contain both soluble and insoluble fibers. – Overall fiber intake is the most important aspect of the diet rather than the type eaten. – Animal meats do not contain fiber. – Functional fiber is a type of fiber that has been extracted or isolated from a plant or manufactured by the food industry, and has been shown to have health benefits. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Two Types of Fiber Soluble fiber Insoluble fiber – Dissolves in water – Does not dissolve in – Easily fermented by water bacteria in the intestine – Not easily fermented by – Examples: Pectins, bacteria in the intestine beta-glucans – Examples: Cellulose, – Health benefits lignins, some hemicelluloses ▪ Lowers cholesterol – Health benefits ▪ Lowers blood glucose ▪ Increases stool bulk ▪ Appetite control ▪ Relieves constipation Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Forms of Dietary Fiber and Their Health Benefits Table 4.1 Forms of Dietary Fiber and Their Health Benefits Insoluble Fiber Type Found in These Foods Reduces the Risk of Cellulose Whole grains, whole-grain cereals, Constipation, diverticulosis, certain Hemicellulose amaranth, bran, bulgur, couscous, oats, cancers, heart disease, obesity rice, quinoa, sorghum, fruits, Lignins vegetables, legumes Soluble Fiber Type Found in These Foods Reduces the Risk of Pectin Citrus fruits, prunes, legumes, oats, Constipation, heart disease, diabetes Beta-glucan barley, quinoa, teff, sorghum, flax seed, mellitus, obesity brussels sprouts, carrots Gums Psyllium Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Polysaccharides Consist of Many Sugar Units (4 of 4) Glycogen – Storage form of glucose in animals – Long, branched chains of glucose – Stored in liver and muscle – Liver glycogen response to blood glucose (BG) levels: –▪ Muscle glycogen can be broken down for energy to the muscle. > - does not regulate BG > olea a – Animal products do not contain glycogen. - is have do not What is Glycogen- video glycogen Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved What is Lactose Intolerance? (1 of 2) Deficiency of lactase, the enzyme that digests lactose · – Lactose maldigestion: Inability to digest lactose due to low levels of the enzyme – Lactose intolerance: When symptoms of lactose maldigestion result in nausea, cramps, bloating, flatulence, and diarrhea Diet recommendations for lactose maldigestion – Most individuals can continue to consume milk, cheese, and yogurt without any side effects. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is Lactose Intolerance? (2 of 2) Diet recommendations for lactose maldigestion (cont’d) – Vary depending on the individual's threshold – Consume small amounts of dairy throughout the day. – Eat lactose-containing foods with a meal or snack. – Whole milk tends to be better tolerated than skim milk. – Cheese has less lactose than milk, especially hard, aged cheese such as Swiss, cheddar, blue, and parmesan. – Consume yogurt with live, active cultures. – Consume lactose-reduced products or take lactose pills or drops with foods. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Much Lactose is in Your Foods? (1 of 2) Table 1 How Much Lactose Is in Your Foods? Food Amount Lactose (grams) Milk, whole, 1%, or skim 1 cup 11 Lactaid milk 1 cup not on Naturally occurring sugars - test – Sugars such as fructose and lactose found naturally in foods – Tend to be nutrient dense – Found in fruit and dairy products Added sugars – Sugars added to processed foods and sweets – Often found in less nutrient dense foods – Provide quick energy from simple carbs Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Slices of an Orange Versus Candy Orange Slices Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Added Sugars Sugars can appear on the food label under many different names. ↑ – The Nutrition Facts panel now distinguishes between natural and added sugars. The number one source of added sugars in the United States is sweetened soft drinks, energy drinks, and sports drinks. – Most of these use high-fructose corn syrup. 1 teaspoon of sugar = 4 grams of sugar e Place to o * Best On Ingredients Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Added Sugars are Used during Food Processing Added sugars – Keep products moist – Provide brown color to pastries and baked goods – Function as preservatives and thickeners – Feed yeast to make bread rise – Make foods taste sweet – Can help make food delicious Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Finding Added Sugars on the Label Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is Diabetes? Diabetes mellitus is a medical condition in which an individual doesn't have enough insulin to meet their insulin needs. In some cases (T2DM), they are resistant to the effects of insulin, which results in a rise in blood glucose levels when the body isn’t able to make enough insulin to compensate for this resistance. (pancreas can make 2-3x normal amount in some cases) – An estimated 29.1 million Americans have diabetes. – Of these, 8.1 million are not diagnosed. – There is a steady rise in Type 2 diabetes in children. – Medical costs associated with diabetes is $170 billion annually in the United States. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Diabetes Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Types and Risk Factors (1 of 6) Type 1 Diabetes – Autoimmune disease where the immune system destroys beta cells of the pancreas ▪ No insulin produced – Usually begins in childhood or early adulthood – 5 to 10 percent of people with diabetes – Requires daily insulin injections (MDI) or insulin pump and blood glucose monitoring (CGM or finger stick glucometer) to manage blood glucose levels - doing the work of the pancreas. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Types and Risk Factors (2 of 6) Type 2 Diabetes – Most common type, 90-95% of people with diabetes have type 2 – Produce insulin but have become insulin resistant ▪ Pancreas overproduces insulin (hyperinsulinemia) but cannot keep up with demand and decreases production overtime – Can go undiagnosed for some time ▪ Damages vital organs and vasculature without individual being aware of it Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Insulin Lowers Blood Sugar Source: https://www.emetabolic.com/locations/centers/tampa/blog/hormones-dna/insulin-hormone-is-a-key-to-unlock-cells/ Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Types and Risk Factors (3 of 6) Type 2 Diabetes (cont’d) – Screening ▪ >45 years of age should be tested every 3 years – Risk Factors ▪ Being “overweight” - correlation, not causation ▪ Inactivity ▪ Age ▪ Family history Image ▪ Social Determinants of Health – Health disparities ↳ related Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Common Symptoms of Elevated Blood Sugar (4 of 6) Polydipsia: Uncontrollable thirst Polyuria: Excessive urination Polyphagia: Strong desire to eat ↑ Blurry Vision ! Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Types and Risk Factors (5 of 6) ↑ ↑ Prediabetes – Impaired glucose tolerance – Fasting blood sugar between 100 m g /d l and 126 illi rams eci iter m g /d l illi rams eci iter – High risk of developing diabetes and heart disease Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  A1C Values and Diabetes A1C measures the average amount of hemoglobin attached to glucose in the blood over the last 3 months. A1C tests are now being used as a diagnostic and screening tool for prediabetes. Table 4.4 Interpreting Blood Glucose and A1C Levels If Fasting Blood Glucose and AiC Levels Are It Means That the Levels Are Considered < 100 m g /d l less than 5.7% illi rams eci iter Normal 100–125 m g /d l 5.7–6.4% Prediabetic * There must be two “positive” tests, done on separate days, for an official diagnosis of illi rams eci iter diabetes. 126 m g /d l * 6.5% or higher illi rams eci iter Diabetic Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Types and Risk Factors (6 of 6) Gestational diabetes – Diagnosed when a woman develops it during pregnancy with no previous diagnosis of diabetes. – The cause is the ineffectiveness of insulin, due to the influence of pregnancy-related hormones, and an inadequate production of insulin needed to meet demands of the body (pancreas not making enough) – Uncontrolled glucose can cause a larger newborn baby and complications during pregnancy and it delivery. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Diabetes Can Result in Long-Term Damage Long-term damage from diabetes – Nerve damage – Leg and foot amputations – Eye diseases – Blindness – Tooth loss – Gum problems – Kidney disease – Heart disease Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Managing Diabetes Nutrition and lifestyle goals for individuals with type 1 and type 2 diabetes are similar. – Eat a well-balanced diet rich in fiber. – Engage in physical activity (at least 30 minutes per day) ▪ Increases insulin sensitivity ▪ Lowers blood pressure and lipids ▪ Supports mental health and wellbeing – Manage and reduce stress – Prioritize quality sleep – Aim for adequate hydration Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Preventing Type 2 Diabetes Research has suggested that the best strategy to lower risk is to – Exercise regularly – Eat a balanced, high-fiber, healthful diet – Manage stress Meeting with a health professional for ongoing support and education can also be helpful - CDCES Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Nutrition: From Science to You Fourth Edition Chapter 5 Lipids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are Lipids and How Do They Differ in Structure? Lipids refer to a category of compounds that include: – Triglycerides – Phospholipids – Sterols Contain carbon, oxygen, and hydrogen Hydrophobic, which means they don't dissolve in water Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Many Lipids are Comprised of Fatty Acids (1 of 2) Building blocks for triglycerides and phospholipids Loading… Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Many Lipids Are Comprised of Fatty Acids (2 of 2) Fat has more kilocalories than carbohydrates or proteins because of the higher ratio of carbon and hydrogen to oxygen. – Fat: 9 kilocalories per gram – Carbohydrate and protein: 4 kilocalories per gram – There are many different fatty acids, which vary by: ▪ Length of the carbon chain ▪ Degree of saturation ▪ Shape Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Length of Fatty Acids Carbon length of fatty acids is 2 to 80 carbons long. – The most common fatty acids contain 12 to 24 carbons. Short-chain fatty acids – 2 to 4 carbons Loading… Medium-chain fatty acids – 6 to 10 carbons Long-chain fatty acids – 12 or more carbons Long-chain fatty acids are the most common type in foods and take longer to digest than short- or medium-chain. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Fatty Acids Vary by Length, Degree of Saturation, and Shape Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Saturation of Fatty Acids (1 of 2) The degree of saturation of a fatty acid is determined by whether the carbons are held together by a double or single bond. Saturated Fatty Acids – All the carbons on the fatty acid are bound to hydrogen. – There are no double bonds, so structure is straight. – They are solid at room temperature. – They have a higher melting point. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Saturation of Fatty Acids (2 of 2) Unsaturated Fatty Acids – Some carbons on fatty acid form a double bond with each other instead of binding to hydrogen. – Monounsaturated fatty acid (MUFA) ▪ Has one double bond – Polyunsaturated fatty acid (PUFA) ▪ Has two or more double bonds – They tend to be liquid at room temperature. – They have a lower melting point. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Saturated vs. Unsaturated Fat Examples of foods with high amounts of saturated fat: – Red meat, bacon, full fat dairy, cheese, butter, coconut oil Examples of foods with mostly unsaturated fat: – Fish, nuts, seeds, olive oil, canola oil, flax, and soy Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Saturated and Unsaturated Fatty Acids Help Shape Foods Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Stability of Fatty Acids (1 of 2) Rancidity: Spoiling of fats through oxidation Double bonds are less stable than single bonds. Loading… Foods with unsaturated fats become rancid faster than foods with saturated fats. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Stability of Fatty Acids (2 of 2) Manufacturers have enhanced the stability of fatty acids by reducing rancidity. Vi + E – Adding antioxidants – Limiting food exposure to oxygen, heat, and light – Hydrogenation > less - common of it results in transfects https://www.youtube.com/watch?v=ukaaesfbO1k Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Triglycerides Are the Most Common Lipid Most common lipid in both foods and the body Make up about 95% of lipids found in foods – Makes meat tender, adds texture to baked goods, preserve freshness A triglyceride molecule has 3 fatty acids connected to a glycerol backbone. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Structure of a Triglyceride Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Structure of a Phospholipid Hydrophilic on one end; hydrophobic on the other Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Phospholipids Differ from Triglycerides Lecithin is a type of phospholipid. Synthesized by the liver Functions of phospholipids: – Used as an emulsifier in foods (e.g., salad dressing, mayonnaise) – Part of the phospholipid bilayer that makes up cell membranes - Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Sterols Are More Complex Than Triglycerides Made of 4 connecting rings of carbon and hydrogen – They do not contain glycerol or fatty acids. – They do not provide energy. eating Cholesterol is the best known sterol. ruish cholesterd – Found in every cell in the body F jor – Helps with numerous body processes crossBott – Precursor to vitamin D, sex steroids, and adrenal corticoids & Phytosterols and phytostanols are major plant sterols. ens Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Structure of a Sterol Stoped here Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Are Lipids Digested, Absorbed, and Transported in the Body? Lipids from foods are primarily in the form of triglycerides. – Lesser extent as phospholipids and sterols During digestion, triglycerides are broken down into free fatty acids, glycerol, and monoglycerides (a glycerol molecule with only one fatty acid attached) Lipases are the enzymes that digest lipids. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Triglyceride Digestion Begins in the Mouth and Stomach The digestion of fat begins in the mouth with chewing. – Food mixes with saliva. The bolus of food travels through the esophagus into the stomach. – Lipase hydrolyzes one fatty acid from the triglyceride, which produces a free fatty acid and a diglyceride. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Focus: Lipid Digestion and Absorption https://www.youtube.com/watch?v=jud8LN1Scfg Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Most Triglycerides Are Digested and Their Components Absorbed in the Small Intestine (1 of 3) Hydrophobic fat molecules cluster together and enter the small intestine, an aqueous environment, in large globules. In the intestine, bile acid emulsifies larger fat droplets into smaller fat droplets. – This allows pancreatic lipase to digest the lipids easily. – The resulting repackaged lipid complex is a micelle. ▪ Contains mono, biles, and phospholipids ▪ Micelles transport the lipid complex across the small intestinal wall. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Most Triglycerides Are Digested and Their Components Absorbed in the Small Intestine (3 of 3) If lipids are undigested and not absorbed in the small intestine, they: – Bind with fiber (soluble) – Are eliminated in the feces Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Role of Bile in Emulsifying Fat https://www.youtube.com/watch?v=lfTnEahTAxw Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Absorption of Dietary Lipids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Lipoproteins Transport Fat HDL and LDL biomarkers are used to determine the health of arteries. LDLs – Carry cholesterol from the liver to the tissues – "Bad cholesterol" – "Lousy" DLs HDLs – Carry cholesterol from the cells to the liver – "Good cholesterol" – "Healthy" DLs Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Focus: Lipoprotein Transport and Distribution Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Functions of Lipids in the Body? Lipids serve several critical roles in the body. – Used as a source of energy – Form body structures (including cell membranes) – Regulate metabolism – Enhance the absorption of fat-soluble vitamins – Provide a layer of insulation to help regulate body temperature – Help cushion the major organs Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Fatty Acids Are Used for Energy Fatty acids provide a concentrated source of kilocalories. – 9 kilocalories per gram Readily available when the body needs energy. – Loading… Excess fat is stored. The body has an unlimited ability to store excess energy as fat in adipocytes. ▪ Fat cells can grow up to 1,000 times their original size. ▪ Additional fat cells are made when fat stores are filled. – Some fat is stored in muscle cells. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Adipocytes Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Fats Are Used for Energy Fats are a powerful fuel source. – Preferred by the heart, liver, and resting muscle – Spares glucose so it is only used by the central nervous system and red blood cells – Provides a backup source of energy between meals – Cannot sustain life during prolonged starvation ▪ Glucose is needed to metabolize fat. ▪ The glycerol portion of fat can make small amounts of glucose. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is ketosis? Body lacks glucose for energy Starts breaking down fat for energy Ketones are a byproduct of fat breakdown Brain will use some ketones for energy Body will also make glucose through gluconeogenesis Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is the keto diet? A very high fat diet: ○ 75% of calories from fat and only 5% from carbs Used to help treat epilepsy in children May result in weight loss and improved blood sugar levels, but is rarely sustainable Risks: constipation, low blood pressure, kidney stones, nutrient deficiencies, heart disease Risks of any diet: disordered eating, negative social impacts, gaining back lost weight and gaining more than lost Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Dietary Fat Aids the Absorption of Lipid Compounds Several essential nutrients require dietary fat for absorption. – Fat-soluble vitamins – Carotenoids – Cholesterol – Phospholipids 20 grams per day are needed to stimulate chylomicrons that transport fat-soluble vitamins. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Triglycerides Stored in Adipose Tissue Insulate the Body and Protect Vital Organs Fat in subcutaneous tissue – Insulates body – Maintains body temperature Fat protects bones and vital organs from trauma. Too much stored fat in the abdominal area can be detrimental to health and increase risk for heart disease, hypertension, and diabetes. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The Liver Uses Cholesterol to Make Hormones, Bile, and Vitamin D The body uses cholesterol as starting material for: – Vitamin D and sex hormones such as estrogen and testosterone – Bile acid Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Phospholipids and Cholesterol Make up Cell Membranes Phospholipids: Part of the phospholipid bilayer in cell membranes Cholesterol: A structural component in cell membranes Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Recommendations for Daily Intake of Triglycerides and Cholesterol? Americans' fat intake is within the guidelines at 33% of total kilocalories, but the type of fat and food that is consumed should be considered. AMDR recommendation – 20-35% of daily kilocalories should come from fat. Excess fat consumption does not lead to weight gain unless excess kilocalories are eaten. For heart health: Replace more saturated fats with monounsaturated and polyunsaturated fats. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Essential Fatty Acids Omega-3 Fatty Acids – Alpha-linolenic acid (ALA) ▪ Converted to eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) Omega 6-Fatty Acids – Linoleic acid ▪ Converted to arachidonic acid EPA and arachidonic acid make eicosanoids. – Hormone-like substances that regulate blood clotting, immune system, inflammation, blood pressure Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Omega 3’s and Omega 6’s Food Sources ALA: Linoleic Acid Linoleic ALA Acid Inefficient conversion in humans Food Sources EPA & DHA: Arachidonic EPA Acid Converts to DHA Eicosanoids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Increase Omega-3 Fatty Acids Increase alpha-linolenic acid (Omega-3 fatty acids) by consuming: – Walnuts, flaxseeds, chia seeds, and canola oil – Fatty fish such as salmon, tuna, mackerel, herring ▪ All fish contain EPA and DHA. Avoid cod-liver oil, as it is very high in vitamin A, which can be detrimental. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Essential Fatty Acids Recommendations The IOM did not establish specific intake recommendations for EPA or DHA To prevent heart disease – 2 servings of fish each week (a total of 6-8 ounces) – Salmon, mackerel, herring, lake trout, sardines and albacore tuna For people diagnosed with heart disease: – Consume 1 gram of essential fatty acids each day – 2–4 grams of E P A and D H A (omega-3’s) daily may reduce blood triglycerides.* *Currently Americans only consume about 0.1–0.2 grams/d of EPA and DHA. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Food Sources of the Essential Fatty Acids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Food Sources of Omega-3 Fatty Acids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Consume More Unsaturated Fats Consume more foods that are high in unsaturated fats, such as: – Vegetable oils: olive, canola, avocado, grapeseed – Soybeans – Walnuts, flaxseeds, wheat germ Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Consume Saturated Fat in Moderation Consume saturated fat foods in moderation: – Animal sources: ▪ Fatty cuts of meat, certain processed foods, whole- milk dairy products, butter, and the skin on poultry – Plant sources: ▪ Coconut oil, coconut milk, and palm oil Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Cholesterol and Plant Sterols Dietary cholesterol comes mainly from animal products. The cholesterol produced in plant cell walls and oils is so minimal that they are considered cholesterol free. Phytosterols and stanols – Lower LDL levels by competing with cholesterol for absorption – Are found in soybean oil, many fruits, vegetables, legumes, sesame seeds, nuts, cereals, and other plant foods – Food manufacturers are fortifying foods with them to help lower cholesterol. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is Heart Disease and What Factors Increase Risk? Cardiovascular disease (CVD) encompasses disorders of a vascular system, including the heart. Heart disease is the number-one killer of adults in the United States. Heart disease begins with atherosclerosis. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Heart Disease Begins with Atherosclerosis Atherosclerosis in the arteries leading to the brain can cause a stroke. Progression of atherosclerosis – Injury to the lining of the arteries promotes inflammation. – LDLs and other lipid substances accumulate at the injured site and become oxidized by reacting with free radicals and metal ions. – Macrophages are attracted to the oxidized LDLs and then form plaques. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Focus: Atherosclerosis Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 5.3 Risk Factors for Heart Disease Uncontrollable Risk Factors Controllable Risk Factors Emerging Risk Factors Age Type 2 Diabetes Blood concentrations of C- Sex High blood pressure reactive protein Family history of heart Smoking High amount of disease Physical inactivity homocysteine Type 1 Diabetes Excess body weight Presence of Chlamydia pneumoniae in the blood Low HDL blood cholesterol Lp(a) protein High LDL blood cholesterol Metabolic syndrome Stress Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Lowering Your Risk of Heart Disease (1 of 2) Primary risk factor is elevated blood lipids. Starting at age 20, have a blood lipid profile analysis every 5 years. Measure cholesterol-to-HDL ratio. Have a risk score calculated. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Lowering Your Risk of Heart Disease (2 of 2) Table 5.4 What Blood Cholesterol Concentrations* Indicate Total Cholesterol (m g /d l ) illi ram eci iter Interpretation < 200 Desirable 200–239 Borderline high Greater than or equal to 240 High LDL Cholesterol (m g /d l ) Interpretation *All lipoprotein concentrations are illi ram eci iter < 100 Optimal measured in milligrams of cholesterol 100–129 Near or above optimal per deciliter of blood (m g /d l ). illi ram eci iter 130–159 Borderline high Source: Data from National 160–189 High Cholesterol Education Program. 190 Very high 2001. Detection, Evaluation, and Greater than or equal to HDL Cholesterol (m g /d l ) illi ram eci iter Interpretation Treatment of High Blood Cholesterol > 60 Desirable in Adults (Adult Treatment Panel III). 40–60 Adequate National Institutes of Health Publication No. 01-3290. < 40 Low Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Consume Less Saturated Fat Diets high in saturated fats raise LDLs in the blood. Dietary cholesterol does not affect LDLs. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Eat More Fish and Plant Foods (1 of 2) Eat at least two, 3.5-ounce servings of fatty fish rich in omega- 3 fatty acids per week. – Choose baked, grilled, broiled, or poached fish. – Limit consumption of EPA and DHA to 3 grams or less per day. ▪ Increases risk for excessive bleeding ▪ May raise both blood glucose and LDL levels ▪ Intakes >3 g only occur with supplementation. ▪ Omega-3 fatty acid supplements should be taken with medical supervision. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Eat More Fish and Plant Foods (2 of 2) Consume more plant foods. – Canola oil, soy, flaxseeds, chia seeds, hemp seeds, and walnuts are rich in ALA. – Choose plant foods rich in soluble fiber. – Consume at least 2 grams of plant sterols a day. ▪ Shown to lower LDL levels by 10 percent ▪ Foods rich in plant sterols include soybean oil, many fruits, vegetables, legumes, nuts, and other plant foods as well as margarine made with plant sterols. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Consume Antioxidants and Phytochemicals Antioxidants and phytochemicals neutralize free radicals, stimulate the immune system to repair tissue damage, and reduce heart disease risk. – Vitamin E, vitamin C, and beta-carotene – Garlic may help lower cholesterol. – Flavonoids may help prevent LDLs from oxidizing. – Nuts reduce LDL levels. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Get Plenty of Exercise and Quit Smoking Exercise raises HDLs, lowers LDLs, and reduces high blood pressure and insulin resistance. – Aim for 30 minutes or more of moderate exercise a day. Quit smoking. – Smoke damages the walls of the arteries and accelerates atherosclerosis. – Smokers are three times more likely to have a heart attack than nonsmokers. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 5.5 Dietary and Lifestyle Changes that May Help Decrease Excess LDL Cholesterol Dietary Changes Lifestyle Changes Consume more foods with Add more physical heart healthy fat activity and exercise into Consume more fruits, your day vegetables, and whole grains Reduce stress Consume more foods rich in soluble fiber Consume more plant- based meals Consume less saturated fat Consume less added sugar, especially in highly refined foods Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Mediterranean Diet Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  A Word about the Protective Effects of Red Wine and Alcohol Alcohol, in moderate amounts, can reduce the risk of heart disease, but mainly in middle-aged adults. – Increases HDL levels – Decreases blood clotting Moderate amounts are defined as no more than: – 1 serving of alcohol per day for females – 2 servings of alcohol per day for males Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Nutrition: From Science to You Fourth Edition Chapter 6 Proteins Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are Proteins? Proteins are macronutrients found in each cell in the body. They participate in every cellular activity that helps the body to function. All enzymes are made of proteins. Some hormones are made of proteins. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Proteins Differ Structurally from Carbohydrates and Lipids (1 of 2) Protein is made up of chains of amino acids that are made based on an individual's DNA. Loading… Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Proteins Differ Structurally from Carbohydrates and Lipids (2 of 2) Excess dietary protein cannot be stored in the body. Proteins contain nitrogen, in addition to carbon, hydrogen, and oxygen. Some protein foods contain sulfur, which is not found in carbohydrates or lipids. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The Building Blocks of Proteins Are Amino Acids (1 of 2) There are 20 amino acids that are used to make proteins. The proteins are classified by the number of amino acids in the chain. – Peptides: Fewer than 50 amino acids ▪ Loading… Dipeptides: 2 amino acids ▪ Tripeptides: 3 amino acids ▪ Polypeptides: More than 10 amino acids – Proteins: More than 50 amino acids ▪ Typically 100 to 10,000 amino acids linked together Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved The Anatomy of an Amino Acid Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The Building Blocks of Proteins Are Amino Acids (2 of 2) Anatomy of an amino acid – Contains an amine group (NH2), a carboxylic acid group (COOH), and a side chain (R group) – The side chains make each amino acid unique and influence the function of each amino acid. Peptide bonds – Form when the carbon of the acid group of one amino acid joins with the nitrogen atom of the amine group of a second amino acid – Formed through condensation – Broken through hydrolysis Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Condensation and Hydrolytic Reactions Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Essential, Nonessential, and Conditional Amino Acids Essential – Must be consumed in the diet – 9 essential amino acids Nonessential – Can be synthesized in the body – 11 nonessential amino acids Conditionally essential – Nonessential amino acids that become essential because the body cannot make them – Examples: Tyrosine and glycine Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The Organization and Shape of Proteins Affect Their Function Four levels of structure – Primary structure: Amino acids are linked together to form a simple linear chain. – Secondary structure: Geometric shape of the Loading… protein that is folded and twisted – Tertiary structure: Three-dimensional globular shape of the protein – Quaternary structure: Two or more polypeptide chains bond together. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved The Organization and Shape of Proteins Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Denaturation of Proteins Changes Their Shape Denaturation (unfolding) of proteins occurs in the presence of: – Heat – Acids – Bases – Salts – Mechanical agitation Altering the shape of the protein alters its function. Primary structure is unchanged by denaturing. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Denaturing a Protein Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Key Steps in Digesting and Absorbing Protein? (1 of 3) Protein digestion begins in the stomach. – The bolus enters the stomach. ▪ Gastrin stimulates the release of HCl. ▪ HCl denatures the protein and converts pepsinogen to pepsin. ▪ Pepsin breaks polypeptides into shorter chains. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Key Steps in Digesting and Absorbing Protein? (2 of 3) Digestion continues in the small intestine. – Polypeptides enter the small intestine and are broken down into smaller peptides. ▪ CCK stimulates the release of proteases by the pancreas. ▪ Proteases break apart the polypeptides to tripeptides and dipeptides. ▪ Dipeptidases and tripeptidases break the dipeptides and tripeptides into amino acids. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 6.2 Enzymes Involved in Protein Digestion Digestive Enzyme Where Released Purpose Pepsinogen From chief cells in the stomach Breaks apart polypeptides into shorter (activated to pepsin by HCl) polypeptide chains Trypsin From pancreas into small intestine Breaks apart peptide bonds Chymotrypsin From pancreas into small intestine Breaks apart peptide bonds Carboxypeptidase From pancreas into small intestine Breaks free one amino acid at a time from the carboxyl end of a peptide chain Aminopeptidase Brush border of the small intestine Breaks free the end amino acids from tri- and dipeptides into single amino acids Tripeptidase Brush border of the small intestine Breaks tripeptides into single amino acids Dipeptidase Brush border of the small intestine Breaks dipeptides into single amino acids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Focus: Protein Digestion and Absorption Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Key Steps in Digesting and Absorbing Protein? (3 of 3) Amino acid absorption – Amino acids are absorbed in the small intestine. – Amino acids are transported to the liver from the intestines via the portal vein. – In the liver, amino acids are: ▪ Used to synthesize new proteins ▪ Converted to energy, glucose, or fat ▪ Released to the bloodstream and transported to cells throughout the body – Occasionally proteins are absorbed intact. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Are Amino Acids Metabolized? (1 of 2) The liver metabolizes amino acids, depending on bodily needs. – Most amino acids are sent into the blood to be picked up and used by the cells. – If the diet is low in carbohydrate, the amino acids are converted into glucose. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Are Amino Acids Metabolized? (2 of 2) Amino acid pools supply the body's ongoing need for protein synthesis. – The body breaks down and makes proteins daily to maintain body structures such as tissues and organs. – Amino acid pools provide a ready supply of amino acids the body uses to create proteins on demand. – Extra protein is used to help the body heal if a person has extensive wounds. – Protein turnover is the process of degrading and synthesizing proteins. ▪ More than 200 grams of protein is turned over daily. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Metabolic Fate of Amino Acids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Deamination Removes the Amine Group from Amino Acids When the amino acid pool reaches capacity, the amino acids are broken down to their component parts for other uses. Deamination occurs when the amine group is removed from the amino acid. Ammonia is formed. Ammonia is converted to urea in the liver. Urea is subsequently excreted in the urine. Certain health conditions, like liver disease, can lead to high blood ammonia levels. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How is Protein Metabolized? Protein can be used for gluconeogenesis. – If too few carbohydrates are consumed, the body converts glucogenic amino acids into glucose. Excess protein can also be converted to fatty acids and stored as triglycerides in adipose tissue. If too few kilocalories are consumed, protein will be oxidized for energy. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is the Function of Protein in the Body? (1 of 2) Provide structural support and enable movement Act as a catalyst – Enzymes speed up reactions. Act as a chemical messenger – Hormones regulate cell actions. Regulate fluid balance (albumin) Help maintain acid-base balance Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is the Function of Protein in the Body? (2 of 2) Transport substances throughout the body – Transport proteins shuttle oxygen, waste products, lipids, some vitamins and sodium and potassium through the blood and cell membranes. Contribute to a healthy immune system – Antibodies are proteins that bind and neutralize pathogens that would harm the body. Provide energy – 4 k cal s/gram ilo orie Improve satiety and appetite control Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Proteins as Transport Channels Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 6.3 The Many Roles of Proteins Role of Protein How It Works Structural and mechanical Proteins are the body’s building materials, providing strength and flexibility to tissues, support and maintenance tendons, ligaments, muscles, organs, bones, nails, hair, and skin. Proteins are also needed for the ongoing maintenance of the body. Enzymes and hormones Proteins are needed to make most enzymes that speed up reactions in the body and many hormones that direct specific activities, such as regulating blood glucose levels. Fluid balance Proteins play a major role in ensuring that body fluids are evenly dispersed in the blood and inside and outside cells. Acid–base balance Proteins act as buffers to help keep the pH of body fluids within a tight range. A drop in pH will cause body fluids to become too acidic, whereas a rise in pH can make them too basic. Transport Proteins shuttle substances such as oxygen, waste products, and nutrients (such as sodium and potassium) through the blood and into and out of cells. Antibodies and the immune Proteins create specialized antibodies that attack pathogens that may cause illness. response Energy Because proteins provide 4 kilocalories per gram, they can be used as fuel or energy. Satiety Protein increases satiety, which can help control appetite and weight. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Much Protein Do You Need Daily? Healthy adults should be in nitrogen balance. – Should consume enough to replace what is used every day Individuals in positive nitrogen balance – Pregnant woman, people recovering from surgery or injury, and growing children Loading… – Should consume enough to build new tissue Individuals in negative nitrogen balance – Immediately after surgery, fighting an infection, or severe emotional trauma – Need to consume enough kilocalories and protein to meet demand Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Nitrogen Balance and Imbalance Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Determine Your Own Protein Needs Protein intake recommendations – RDA: 0.8 g /k g (0.36 g/pound) daily for adults over 18 rams ilo ram – AMDR: 10 to 35 percent of total daily kilocalories The American College of Sports Medicine, the Academy of Nutrition and Dietetics, and other experts advocate: – 50-100% more protein for competitive athletes participating in endurance exercise or resistance exercise. (Typically this population eats more and therefore gets additional protein. Supplements are generally not needed.) Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Best Food Sources of Protein? (1 of 4) Not all protein is created equal. – High-quality protein: ▪ Is digestible ▪ Contains all essential amino acids ▪ Provides sufficient protein to synthesize nonessential amino acids Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Best Food Sources of Protein? (2 of 4) Several methods have been developed to determine the protein quality of foods. – Amino acid score ▪ Composition of essential amino acids of a protein compared with a standard, usually egg protein – Protein digestibility corrected amino acid score (PDCAAS) ▪ Includes the digestibility of the protein and the amino acid score ▪ Used by the FDA to determine the %DV of proteins in a serving of food – Biological value ▪ How quickly the nitrogen from the absorbed protein is synthesized into body protein Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Best Food Sources of Protein? (3 of 4) Complementary and complete proteins – Complete proteins ▪ Contain all 9 essential amino acids ▪ Usually, animal sources are complete proteins. – Exceptions include: Soy, quinoa, buckwheat, and hemp seed ▪ Are considered higher quality – Incomplete proteins ▪ Low in one or more essential amino acids, referred to as limiting amino acids ▪ Usually plant sources (Exception: Gelatin) – Complementary proteins ▪ Combining an incomplete protein with a food that supplies the limiting amino acids (e.g., combining grains and legumes) Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Are the Best Food Sources of Protein? (4 of 4) Eggs, meat, fish, soy, and dairy contain significant amounts of protein. Meat, poultry, and fish provide about 7-8 g of protein per ounce – A 3-ounce serving of cooked meat, poultry, or fish: ▪ Provides 21 to 25 grams of protein ▪ Is about the size of a deck of cards Eating a wide variety of foods is the best approach to meeting protein needs. Taking protein supplements is unnecessary and generally not recommended. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Food Sources of Protein (1 of 2) Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Food Sources of Protein (2 of 2) Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Happens If You Eat Too Much Protein? Too much protein: – May increase risk for heart disease ▪ High intake of protein sources with high saturated fat ▪ Choose a variety of plant sources of protein to reduce risk for heart disease – Increases risk for kidney stones ▪ A diet high in animal protein and low in carbohydrate lowers urine pH, which can raise the risk of developing kidney stones. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Happens If You Eat Too Much Protein? – Increases risk for osteoporosis ▪ High protein intake with too low calcium intake can lead to increased urinary calcium losses. ▪ High-protein diets with adequate calcium (especially from dairy sources) protect bone. ▪ Too low protein intake can lead to bone loss in elderly men and women. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Happens If You Eat Too Much Protein? Too much emphasis on protein in a diet can crowd out or displace other nourishing, equally important food choices from the diet such as whole grains, fruits, and vegetables. – Aim for balance on your plate. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Happens If You Eat Too Little Protein? Inadequate protein – Cells lining the GI tract are not sufficiently replaced as they slough off. – Digestive function is inhibited. – Absorption of food is reduced. – Intestinal bacteria get into the blood and cause septicemia. – The immune system is compromised due to malnutrition and cannot fight infection. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What Happens If You Eat Too Little Protein? Inadequate protein and/or calories can lead to Protein Energy Malnutrition (PEM) – Protein is used for energy rather than for its other functions in the body. – Other important nutrients are in short supply. – More prevalent in infants and children ▪ 1 in 8 people in the world (most are children) do not have adequate protein intake, kcal intake, or both. – Three types of PEM: Kwashiorkor, marasmus, marasmic kwashiorkor Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Types of PEM: Kwashiorkor Severe protein deficiency – Generally the result of a diet high in grains and deficient in protein Symptoms include: – Edema in legs, feet, and stomach – Diminished muscle tone and strength – Brittle hair that is easy to pull out – A pale, sad, and apathetic appearance – Being prone to infection, rapid heart rate, excess fluid in lungs, pneumonia, septicemia, and water and electrolyte imbalances Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Types of PEM: Marasmus Results from a severe deficiency in kilocalories – Frail, emaciated appearance – Weakened and appear apathetic – Often cannot stand without support – Appears old beyond their years – Hair thin, dry, and lacks sheen – Low body temperature and blood pressure – Prone to dehydration, infections, and unnecessary blood clotting Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Types of PEM: Marasmic Kwashiorkor Chronic deficiency in kilocalories and protein – Edema in legs and arms – A “skin and bones” appearance – With treatment, the edema subsides and appearance becomes more like someone with marasmus. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Vegetarian Diets People choose vegetarian diets for a variety of reasons, including: – Ethical – Religious – Environmental – Health* – Trends Vegetarians must consume adequate amounts of a variety of foods and should plan meals well. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 6.5 The Many Types of Vegetarians Type Eats Avoids Lacto-vegetarian Grains, vegetables, fruits, Meat, fish, poultry, and legumes, seeds, nuts, dairy foods eggs Lacto-ovo-vegetarian Grains, vegetables, fruits, Meat, fish, and poultry legumes, seeds, nuts, dairy foods, eggs Ovo-vegetarian Grains, vegetables, fruits, Meat, fish, poultry, dairy legumes, seeds, nuts, eggs foods Vegan Grains, vegetables, fruits, Any animal foods (meat, legumes, seeds, nuts fish, poultry, dairy foods, eggs) Pescetarian Grains, vegetables, fruits, Meat and poultry legumes, seeds, nuts, dairy foods, eggs, and fish Semi-vegetarian A vegetarian diet that occasionally Meat, fish, and poultry on includes meat, fish, and poultry occasion Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Benefits of a Vegetarian Diet Benefits of a balanced vegetarian diet include reduced risks of: – Heart disease – High blood pressure – Stroke – Type 2 diabetes – Certain cancers Eating a “plant-forward” diet, one that isn’t all vegetarian but includes a focus on plant based foods can also achieve many of these health benefits. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Risks of a Vegetarian Diet Potential risks of a vegetarian diet include low intake of key nutrients. – Protein – Calcium – Iron – Vitamin B12 – Zinc – Vitamins A and D – Omega-3 fatty acids (DHA & EPA) In addition, adhering to any diet means less flexibility with meals and in general more planning. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 6.6 Suggested Servings for a Healthy Vegetarian Diet (1 of 2) Food Group Number of Serving Size Calcium-Rich Foods (8 servings Servings daily) Grains 6 Bread, 1 slice Whole-wheat bread, 1 slice Grains 6 Cooked grain or cereal, 1 half cup Calcium-fortified cereal, 1 oz Grains 6 Ready-to-eat cereal, 1 oz Blank Legumes, nuts, and other 5 Cooked beans, peas, or lentils, 1 half cup Cow’s milk or yogurt, 1 half cup protein-rich foods Calcium-fortified soy milk, 1 half cup Tofu or tempeh, 1 half cup Cheese, 3 fourth ounces Nut or seed butter, 2 t b sp a le oon Nuts, 1 fourth cup Meat analog, 1 oz Egg, 1 Vegetables 4 Cooked vegetables, 1 half cup Bok choy, collards, broccoli, Chinese cabbage, kale, mustard greens, or okra; 1 cup cooked or 2 cups raw Vegetables 4 Raw vegetables, 1 cup Calcium-fortified tomato juice, 1 half cup Vegetables 4 Vegetable juice, 1 half cup Blank Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Table 6.6 Suggested Servings for a Healthy Vegetarian Diet (2 of 2) Food Group Number of Serving Size Calcium-Rich Foods (8 servings Servings daily) Fruits 2 Medium fruit, 1 Cut-up or cooked Calcium-fortified fruit juice, 1 half cup fruit, 1 half cup Figs, 5 Fruit juice, 1 half cup Dried fruit, 1 fourth cup Fats 2 Oil, 1 t sp ea oon Blank Soft margarine, 1 t spea oon Mayonnaise, 1 t sp ea oon Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved