Study Guide for Exam 1 Chapter 1 - 6 PDF

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Professor Martha Stewart...

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Human Nutrition Study Guide: Chapters 1 - 6 75 Questions + few extra credit questions Chapter 1 & 2 ● Definitions of nutrition, diet, food, nutrient, essential nutrient, nutrient requirement, What are phytonutrient/phytochemicals and functional foods. Know some examples. ○ Nutrition: The scientific study of nutrients and how the body uses them and the study of human behaviors related to food and eating. Has foundation in biology, biochemistry, physiology ○ Diet: The usual pattern of food choices - combination of all the foods/beverages consumed ○ Food: (in both liquid and solid forms) Products derived from plants and/or animals that can be taken into the body/consumed and yields energy & nutrients ○ Nutrient: Chemicals necessary for proper body functioning used by the body to provide energy, structural materials and regulating agents to support growth, maintenance and repair of tissues. May be inorganic or organic. 6 classes. ○ Essential nutrient: indispensable nutrients; Nutrients a person must obtain from food because the body cannot make them for itself in sufficient quantity to meet physiological needs. Lack causes deficiency disease ○ Nutrient requirement: The foods and liquids necessary for normal physiologic function ○ Phytochemicals: “phyto” = plant; beneficial chemicals found in plants; thought to have health-protecting qualities ■ Example: Carotenoids - alpha-carotene, beta-carotene, lutein, lycopene, zeaxanthin; found in carrots, yellow, orange fruits. May help neutralize free radicals that cause cell damage ■ Phenolics - antioxidant, anti-inflammatory ■ Organosulfides - isothiocyanates, indoles, allylic sulfur compounds; found in garlic, onions, antioxidant ■ Alkaloids - caffeine ■ Glycosides - saponins; found in chickpeas, beans, oats, grapes ■ Capsaicinoids - capsaicin; found in chili peppers ■ Fructooligosaccharides - onions, bananas ○ Functional foods: foods that contain bioactive components that provide health benefits beyond their nutrient contributions; food that contains something extra above the nutrient value - If you eat it for the nutrient purpose, you’re eating it as a functional food ■ Example (whole foods): Banana - Potassium, Oatmeal - Fiber ■ Example (fortified/modified foods): Orange Juice - Calcium ● What are the 6 classes of nutrients? Why are they important? What nutrient makes up the largest proportion of the body? ○ Inorganic Nutrients

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■ Minerals ■ Water - Greatest percentage of the body ○ Organic Nutrients ■ Carbohydrate ■ Lipid (fat) ■ Protein ■ Vitamins ○ Importance: Because they are essential nutrients; necessary for the body to function properly; lack of it causes deficiency disease What does macronutrient and micronutrient mean? Of the 6 classes of nutrients, which are macronutrients and which are micronutrients? ○ Macronutrient: nutrients needed in large amounts daily that provide energy; carbohydrates, proteins, fats and water (but water is not energy-providing) ○ Micronutrient: nutrients needed in much smaller amounts relative to energy molecules; vitamins and minerals What does organic and inorganic mean in terms of the chemistry of the nutrients? ○ Organic = presence of a carbon atom; organic compounds are created by something already living ○ Inorganic = absence of a carbon atom Food energy is measured in calories? Which of the six classes of nutrients can yield energy when metabolized in the body? Which classes cannot? What non-nutrient beverage also provides energy? ○ Food energy is measured in kilocalories or Calorie ○ Carbohydrates, proteins and fats can yield energy ○ Vitamins, minerals and water cannot yield energy ○ Alcohol How many calories/gram are provided by each class of energy yielding nutrients and the one non-nutrient? Be able to calculate total calories provided by a meal if you are given the grams of carbs, protein, fat and alcohol. Bring a calculator (NO PHONE) ○ carbs: 4 kcal/g ○ protein: 4 kcal/g ○ fats: 9 kcal/g ○ alcohol: 7 kcal/g Know the food groups as summarized in the Dietary Guidelines/ChooseMyPlate. What are some commonly eaten foods in each food group? ○ Fruit ■ Strawberries, watermelon, apples, bananas, grape, mango, peach ○ Vegetables ■ Broccoli, spinach, carrots, tomatoes, mushroom, onion, beans

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○ Protein foods ■ Beef, chicken, almonds, walnuts, salmon, shrimp, black beans, pinto beans ○ Grains ■ Quinoa, brown rice, oatmeal, popcorn, whole wheat bread ○ Dairy ■ Milk, cheese, yogurt What are categories of foods that people commonly consume but are not considered a food group according to the Dietary Guidelines? ○ Fats and oils ○ Sweets and sugary foods ○ Alcohol What is a nutrient deficiency? Nutrient toxicity? (don’t have to know toxicity part well) ○ Nutrient deficiency: Undernutrition that leads to malnutrition; lack of nutrient in the diet; malabsorption ○ Nutrient toxicity: Nutrients that do not supply calories to the diet can be dangerous if you take too much; Fat soluble vitamins are especially prone to causing adverse effects because you store them in your adipose tissue ie. toxic levels of vitamin A can cause birth defects What is the difference between acute and chronic diseases? ○ Acute: severe, sudden and rapid in onset; short course ie. broken bone ○ Chronic: long-developing syndrome ie. osteoporosis What is a risk factor? How does a risk factor relate to a given disease state? What is the difference between a person with one risk factor for a disease and the person with 5 risk factors? ○ Risk factor: any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury ○ Ie. Risk factors such as high blood pressure, obesity and high cholesterol can lead to or worsen one’s cardiovascular disease ○ The more risk factors someone has the more they tend to cluster and one thing can lead to another (physical inactivity + obesity + high blood pressure + diabetes -> cardiovascular disease rather than just obesity -> cardiovascular disease) Why is control of calories important? What will happen if you consume more calories than your body needs? What will happen if you consume less than your body needs? ○ Control of calories = energy; Energy in needs to be roughly equal to energy out in order to prevent unwanted weight gain or loss ○ If you consume more calories: gain weight; if you consume less: lose weight What is nutrient density? What is energy density? What are some examples of nutrient dense foods? What are some examples that are less nutrient dense and more energy dense? Be able to distinguish between foods.

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○ Nutrient density: nutrients provided by a food relative to the calories/energy in the food (orange juice with pulp vs. soft drink) ○ Energy density: amount of energy (calorie) provided relative to the weight of the food (candy bar vs. cucumber) ○ Nutrient dense foods: retain naturally occurring components such as vitamins, minerals, dietary fiber, phytonutrients (ie. include all vegetables, fruits, whole grains, eggs, beans and peas, seafood, lean meats and poultry) What is an empty calorie food? ○ Foods and beverages composed primarily or solely of sugar, fats or oils, or alcohol-containing beverages ○ Example: Cakes, cookies, pastries, doughnuts, sugar-sweetened drinks, ice cream What are discretionary calories? What foods choices might fall into the discretionary calorie category? ○ Discretionary calories: excess calories to enjoy once your required nutrient needs are met; not necessary for a healthy diet and are too high in saturated fat and/or added sugars, added salt or alcohol and low in fiber ○ Example: Cakes, sweet biscuits, pies, ice cream, pastries and desserts Read over the 2015 Dietary Guidelines Executive Summary and be able to recognize the main points. Who are the guidelines for? Do the guidelines apply only to healthy people or also to people with chronic diseases? What is the overall purpose (aim) of the Dietary Guidelines? ○ Main points ■ Follow a healthy eating pattern across the lifespan ■ Focus on variety, nutrient density and amount ■ Limit calories from added sugars and saturated fats and reduce sodium intake ■ Shift to healthier food and beverage choices ■ Support healthy eating patterns for all ○ The guidelines are for Americans for ages 2 years and older ○ Applies to both healthy people and those with chronic diseases ○ Aims include (1) attaining and maintaining a healthy weight (2) reducing risk/improving management of chronic disease (3) promoting overall health What is a food label? What information is provided on a food label? Know how to read/interpret the Nutrition Facts section of a food label ○ Food label contains a variety of information about the nutritional value of the food item ○ Serving size, number of calories, grams of fat, included nutrients, cholesterol, sodium, carbohydrates, protein

Digestion ● Know the sequence of organs of the GI tract from beginning to end, and the accessory organs. Be able to identify them on a diagram ○ Mouth/salivary glands -> esophagus -> stomach -> small intestines -> large intestine -> rectum -> anus ○ Accessory organs: liver, gallbladder, pancreas ● What is digestion? What are the two types of digestion that occur in the gi tract? What are some fluids that are secreted in the gi tract to aid digestion? ○ Digestion: a process of transformation where solid and liquid foods are broken down into individual nutrient molecules that the body can use ○ Two types: absorption and elimination ○ Fluids: saliva, gastric juices, bile ● What is absorption? What is being absorbed? ○ The uptake of nutrients from the GI tract by cells of the GI tract (enterocytes) ● What is excretion? What is being excreted? ○ Elimination of waste and residual products of metabolism from the body ● What is the lumen? What happens in the lumen? ○ The inside surface and space of the GI tract where digestion occurs ● What is the purpose of the GI tract? What is its shape? Are the muscles of the gi tract flexible or rigid? Are they permeable? ○ Purpose: break food down into nutrients, which can be absorbed into the body to provide energy ○ GI tract: continuous flexible and muscular tube-like organ system with many different specialized organs with specific cells that perform a variety of functions ○ Semi-permeable membrane - things can be secreted/come out and absorbed/get in from it ie. waste products can get out ● What are sphincters? What do they do? What is their role in the gi system? ○ Sphincters: 6 circular muscles surrounding sections of the GI tract that differentiate on section from another ○ The lower esophageal sphincter and the pyloric sphincter are two important sphincters whose functioning can impact a person’s comfort level after eating ○ Periodically open and close; control the pace of movement of GI tract contents ● What role does the appendix play? To which body ‘system’ does it belong? (gi, vascular, neurological, immune, endocrine, etc.) ○ Appendix is the repository for good bacteria that populates the large intestine ■ What do good bacteria (probiotics) need to feed? Prebiotics (need soluble fiber). someone is not getting adequate amounts of soluble fiber so that bacteria overgrows ○ Part of immune system

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What is a bolus? ○ A lump of food and saliva formed in the mouth by chewing What is chyme? When/where does food change from a bolus to chyme? ○ Semifluid mass of partially digested food and digestive secretions that is formed in the stomach and intestine during digestion ○ Food enters into the stomach as a bolus and leaves as watery chyme (“juice”) What is peristalsis and why is it important? ○ Rhythmic contractions created by circular and longitudinal muscles working together to move food along the GI tract ○ Important bc it propels bolus along the GI tract, allowing for proper digestion What is motility and why is it important? Does increasing motility speed up or slow down gi tract contents? What about decreasing motility? ○ The movement of food thru the pharynx, stomach, small/large intestines and out of the body ○ Increasing motility speeds up GI tract contents and vice versa Know that the gi tract secretes various but distinct fluids (secretions) in each part and each has a specific purpose. ○ Saliva: moisten food for easy passage, protective role, carb digestion ○ Gastric juices ■ Mucus cells: protects lining, water helps liquefy bolus ■ Parietal cells: HCl uncoil proteins, intrinsic factor aids absorption of vitamin B-12 ■ Chief cells: enzymes that digest proteins and fats ■ G cells: produce gastrin hormone ○ Bile: produced in the liver, stored in gallbladder, helps emulsify fat globules and aids absorption ○ Pancreatic juices: released via ducts into duodenum, enzymes act on all three energy nutrients (amylase, protease, lipase), helps neutralize the acidic chyme coming from stomach (sodium bicarbonate) ○ Small intestinal juices ■ Crypts: secretion of intestinal enzymes, water, bicarb ■ Goblet cells: secretion of mucus ■ Immune system cells: protect against ingested germs Enzymes are secretions that digest nutrients into their smallest absorbable components ○ Amylases -> starch ○ Lipases -> lipids ○ Proteases -> proteins

Where is the site of most nutrient absorption specifically? What is the structure that enables nutrient absorption (hint: absorptive cells lining the villi of the si a nd their microvilli ) ○ Small intestine ○ hint: absorptive cells lining the villi of the si a nd their microvilli ○ villi and microvilli (enterocytes) ● What two systems of the body help control communication and coordinate  the actions of the gi tract? ○ Nervous system and endocrine system

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Carbohydrates ● Carbohydrates are a class of nutrient that comes in several different forms/types. Some carbohydrates provide energy, others do not. What are the main types of dietary carbohydrate? How many calories are provided by each type? ○ Simple and complex: starches and fibers ● How many carbons do dietary monosaccharides have? What are the names of the 3 monosaccharides? Which monosaccharide is also known as blood sugar? ○ 6 carbon atoms ○ Glucose (also called dextrose, blood sugar) ○ Fructose (levulose) ○ Galactose (milk sugar) ● What are disaccharides? ○ Simply sugar comprised of two monosaccharides ● What are the names of the three dietary disaccharides? ○ Maltose, sucrose, lactose ● What foods are they most typically found in? ○ Sucrose: fruit, honey table sugar, corn syrup, sugarcane, sweet veggies ○ Lactose: milk and dairy products ○ Maltose: malt beer, malted milk balls ● Which monosaccharides are in each disaccharide? ○ Maltose: glucose and glucose ○ Sucrose: glucose and fructose ○ Lactose: glucose and galactose ● Which disaccharide is typically called table sugar? ○ sucrose ● Why is it sweeter than the other disaccharides? ○ 1 molecule is changed and taste buds perceive it as different -> has fructose in it ● Which disaccharide comes from milk? ○ Disaccharides: pairs of monosaccharides

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○ Sucrose (glucose + fructose) - table sugar ■ Fruit, honey, table sugar, corn syrup, sugar beets ■ Sucrose is much sweeter than other disaccharides because it binds much more tightly to sweetness receptors on the tongue ○ Lactose (galactose + glucose) ■ Milk, yogurt What is a polysaccharide? ○ A complex carbohydrate that is comprimes of 10 or more monosaccharides Two types of polysaccharide are found in plants. What are these called? What distinguishes one from the other in terms of its digestibility and absorption by humans? What type of foods are these polysaccharides found? ○ Polysaccharide: polymeric carbohydrate molecules composed of more than 2 chains of monosaccharides ○ Two types: starch and fiber ■ Starch can be found in grains, potatoes, nuts, seeds ■ Fiber can be found in beans, nuts, oatmeal, wheat, corn, rice bran ○ Starch can be digested by amylase but humans cannot digest the fiber bonds holding glucose together although animals have the enzymes to break the bonds so they can digest and absorb the glucose A third kind of polysaccharide is made and stored in the body by the liver and by muscle cells of humans and animals. What is it called? ○ Glycogen Why does the body store it? ○ Muscles and liver Does the liver or muscle release glucose to help maintain normal blood glucose concentrations between meals when blood sugar is at baseline or lowered? ○ Liver Why would we usually never eat Glucose? ○ Usually not eat because it gets used up when an animal dies Is this the reason that we do not obtain carbohydrates from meat, poultry and fish? ○ Yes Fiber is indigestible in the human colon. What are the two types/categories of fiber? What are some benefits of each of these (See Table 4.9)? Which type helps with constipation and which helps reduce cholesterol and thus decreases the risk of heart disease? Know a few foods (from Tables in textbook and lecture notes) that provide each type of fiber. ○ Soluble Fiber: delays stomach emptying; slows glucose absorption; can lower blood cholesterol ○ Goods: apples, banana, citrus fruits, carrots, oats, barley, beans

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○ Insoluble Fiber: increases fecal bulk and speed fecal passage through gi tract; may increase bowel movements ○ Goods: all plants; wheat, rye, brown rice, vegetables, whole grains, wheat bran In what part of the gi tract are most digestible carbohydrates absorbed into the body? ○ Small intestine In terms of energy utilization, which monosaccharide is used as fuel for the brain, muscles and most other cells in the body? ○ Glucose Which organ preferentially utilizes fructose and galactose? ○ Liver will use this or its energy needs and make glycogen What does it do with excess fructose and galactose? ○ Converted into glucose or fat In what foods are fructose and galactose found? ○ Fructorse: ripened beets, sugar cane, carrots, grapes, peaches, apples ○ Galactose: milk sugar -> only in dairy products What happens to that organ when excessive amounts of fructose and galactose rich foods are consumed on a regular basis? ○ Liver will become a fatty liver and become overweight What is lactose intolerance? ○ Lactose intolerance means that you don’t digest it well What are the symptoms of lactose intolerance? ○ Gas, bloating, diarrhea, pain, discomfort What is the name of the enzyme that is lacking in people with lactose intolerance? ○ Lactase What category of nutrient is lactose? ○ carbohydrate In what foods is it found? Not found? ○ Milk and dairy products What types of dairy products could a person with lactose intolerance consume? ○ Yogurt, aged cheeses, low-fat dairy products in small amounts, dairy products eaten with a lactase pill What is the RDA for dietary carbohydrates and fiber? What is the minimum grams of carbohydrate needed by most humans in a day? ○ Carbohydrates: 130 grams per day (minimum) ○ Fiber: 14 grams per 1000 kcalories or 20-35 grams per day depending on caloric levels, age and sex What is hypoglycemia and hyperglycemia? ○ Hypoglycemia: low blood sugar/low blood glucose ○ Hyperglycemia: Excess of glucose in the bloodstream

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What disease is associated with prolonged excessively high levels of blood glucose? ○ Insulin resistance/Type 2 diabetes mellitus What damage does this disease cause in the body? ○ Causes damage to blood vessels, blood proteins, blood lipids, tissues such as retina, kidneys, nerves, and heart What are some strategies to reduce your risk of this disease? ○ Diet and exercise If you have this disease, what is a mealtime strategy to help manage/stabilize blood glucose levels and prevent dangerous spikes? ○ Cut back on carbs and eat more lean protein, fruits, and vegetables. Fiber can also be helpful. Avoid white rice, white bread, soda and other sweet drinks, red meat, fast food, packaged food, whole milk What is gly...