Nutrition Chapter 1 Notes PDF

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Nutrition: Science of food; the nutrients and the substances therein; their action, interaction, and balance in relation to health and disease; and the process by which the organism (i.e., body) ingests, digests, absorbs, transports, utilizes, and excretes food substances

Nutrient: Chemical substance in food that contributes to health. Nutrients nourish us by providing energy, materials for building body parts, and factors to regulate necessary chemical processes in the body. ●

Substances that make food important to life (there are 6 in total)

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Nutrients are divided into 6 main classes: Carbohydrate, protein, fat, water, vitamins, and minerals

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Carbohydrates, lipids, and amino acids yield energy

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Water, vitamins, and minerals do not yield energy

Essential Nutrients 1. Have a specific biological function 2. Removing the nutrient leads to a decline in normal human biological function 3. Adding it back when stores are low restores biological function back to normal

Functional Categories of Nutrients Provide Energy Most carbohydrates Proteins Lipids Promote Growth and Development Proteins Lipids Some vitamins Some minerals

Regulate Body Processes Proteins

Water Some Lipids Some vitamins Some minerals

Macronutrient: Nutrient needed in gram quantities in the diet. Fat, protein, and carbohydrates are macronutrients ●

Needed in the body in large amounts, g or kg, (protein, carbohydrates, fat)

Micronutrient: Nutrient needed in milligram or micrograms quantities in a diet. Vitamins and minerals are micronutrients. ●

Needed in the body in small amounts, mg or µg = micrograms (vitamins and minerals)

Carbohydrates: Composed mainly of hydrogen, oxygen, and carbon ●

Found in fruits, vegetables, grains, grains, beans, and sugar

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Provides stored energy

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Simple carbohydrates

Ex. Glucose (Provides 4 calories per gram kcal/gram major source of energy in cells) (Fiber provides little energy because it cannot be broken down) Sucrose ● Complex carbohydrates Ex. Starch in grains ● Glycogen

Lipids: Lipids are compounds composed of carbon, hydrogen, and oxygen ●

Fats refer to lipids that are solid at room temperature

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Oils is lipids liquid at room temperature Lipids yield more energy than carbohydrates (about 9 calories per gram kcal/g)

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Lipids are insoluble in water, but can dissolve in organic solvents

Saturated fats have numerous amounts of health risks (aka trans fat) Unsaturated fats are Linoleic acid Alpha-linolenic acid-- they are essential nutrients ● Roles include structural components of the cell membrane, regulate blood pressure, and nerve transmission Triglyceride: Major form of lipid in the body and in food; composed of 3 fatty acids bonded to glycerol, an alcohol. (Composed of 3 fatty acids attached to a glycerol molecule)(Fatty acids are long chains of carbon flanked by hydrogen with an acid group attached to the end opposite glycerol)

Proteins: Composed of carbon, hydrogen, nitrogen, and oxygen ● ●

Main structural material in the body (Major part of bone and muscle) Important components in blood, cell membranes, enzymes, and immune factors

Enzyme ●

Compound that speeds the rate of a chemical process but is not altered by the process. Almost all enzymes are proteins (some are made of nucleic acids).

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Proteins provide about 4 calories per gram, but the body uses little protein to meet its energy quota

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Proteins form when amino acids bond together (about 20 common amino acids are found in food, but 9 of these are essential nutrients and 1 additional for infants)

Vitamins ●

Composed of carbon, hydrogen, oxygen, phosphorus, sulfur, and others

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Main function is to enable chemical reactions to occur in the body

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Chemical reaction: Interaction between 2 or more chemicals that changes both chemicals

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13 types of vitamins are divided into 2 groups

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Fat soluble vitamins dissolve in fat (A,D,E,K) Vitamins C and B are water soluble Cooking is more likely to destroy water soluble vitamins

Minerals ●

Minerals are simple and inorganic substances which do NOT contain carbon or hydrogen

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Minerals function in a group of one or more atoms of the same atoms in a combination of mineral groups

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Not destroyed during cooking

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Do not yield energy, but are essential to normal function of the body (Play key roles in the nervous system, skeletal system, and water balance)

Divided into 2 groups.... Trace and major ● ●

Major Minerals are required in gram amounts (Ex: Sodium, Potassium, Chloride, Calcium and Phosphorus) Trace Minerals are required less than 100 mg daily (Ex:Iron, Zinc, Copper and Selenium)

Water Water is inorganic Acts as a lubricant and is needed to transports nutrients throughout the cells 1. Needed in large quantities 2. Regulates temperature 3. The body makes some water as a by-product of metabolism

Metabolism: Chemical processes in the body that provide energy in useful forms and sustain vital activities.

Phytochemical: Physiologically active compound in plants that may provide health benefits. (Plant components in fruits, vegetables, legumes, and whole grains)

Zoochemical: Physiologically active compounds in foods of animal origin that may provide health benefits. (Components of animals) Not essential nutrient, but found to have health benefits (Ex: Reducing risk of cancer)

Energy sources and use ●

Alcohol is a source of energy supplying about 7 calories per gram, but it is no a nutrient because it has no required function to the body

Calorie is typically referred to the amount of energy a food yields Calorie: "the amount of heat it takes to raise the temperature of 1 gram of water by 1 degree Celsius" Kilocalorie (kcal): Heat energy needed to raise the temperature of 1000 grams (1 L) of water 1 degree Celsius; also written as Calorie. (Carbohydrates 4 kcal/g, Protein 4 kcal/g, Alcohol 7 kcal/g, and Fat 9 kcal/gram) Kilojoules: 1000J= 1KJ and 1 Kcal= 4.18 KJ To calculate energy percentage intake do the formula with the values above,, divide by kcal, and multiple final value by 100%

Ion: Atom with an unequal number of electrons and protons. ● ●

Negative ions (anions) have more electrons than protons and carry a negative charge; positive ions (cations) have more protons than electrons and carry a positive charge.

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The body uses energy in order to balance ions, build new components, move muscle, and transmit nerve impulses

Hunger: Primarily physiological (internal) drive for food. Apetittie: Primarily psychological (external) influences that encourage us to find and eat food, often in the absence of obvious hunger

Reasons for making Food Choices 1. Food flavor, texture & appearance preferences 2. Culture 3. Lifestyle, routines, and habits 4. Environment, food cost, and availability 5. Food marketing 6. Nutrition concerns, knowledge, and beliefs

Nutritional Health Status: A well nourished person has a total of 1 pound of each of the 6 types of nutrients and 20 grams of minerals

Desirable Nutrition Status: State in which body tissues have enough of a nutrient to support normal functions and to build and maintain surplus stores (Adequate liver stores of iron, adequate blood levels of iron-related compounds, and normal functioning of red blood cells)

Undernutrition: Failing health that results from a longstanding dietary intake that does not meet nutritional needs. (Decline in iron-related compounds in the blood which reduces the ability of the red blood cells to carry oxygen to body tissues and in turn causes fatigue on exertion, poor body temperature, and paleness

Subclinical: Present but not severe enough to produce signs and symptoms that can be detected or diagnosed (e.g., a subclinical disease or disorder).

Sign: Physical attribute that can be observed by others, such as bruises.

Symptom: Change in health status noted by the person with the problem, such as a stomach pain. Overnutrition: State in which nutritional intake greatly exceeds the body's needs. (Excess liver stores of iron, which damages the liver)

Health Objectives for the US 1. Health promotion important since 1970s 2. Healthy People 2020 Issued by USDHHS 10-year goals for improving the health of all Americans

Anthropometrics: Pertaining to the measurement of body weight and the lengths, circumferences, and thicknesses of parts of the body.

Biochemical: Assessment focusing on biochemical functions (e.g., concentrations of nutrient by-products or enzyme activities in the blood or urine) related to a nutrient's function.

Clinical: Physical evidence of diet-related disease. This type of assessment focuses on the general appearance of skin, eyes, and tongue; evidence of rapid hair loss; loss of sense of touch; and loss of ability to cough and walk.

Dietary: Assessment that focuses on one's typical food choices, relying mostly on the recounting of one's usual intake or a record of one's intake of the previous day. Environmental: Assessment that focuses on one's education and economic background and other factors that affect one's ability to purchase, transport, and cook food and follow instructions given by health-care providers.

Limits to Assessment 1. Signs and symptoms of deficiencies are not specific (diarrhea, skin conditions and fatigue are not specific) 2. May take a long time to appear and may not be diet related 3. May take a long time to affect health

Genetics and Nutrition: Lifestyle, diet and genetics influence disease risk 1. DNA directs individual's use of nutrients 2. Explains the history and potential for disease

Genetic mutations: Change in the chemistry of a gene that is perpetuated in subsequent divisions of the cell in which it occurred; a change in the sequence of the DNA. (increase risk for some diseases)

Gene therapy: Corrects damaged DNA

Genetic testing: Determines probability of getting a disease (Genetic profile can allow you to change certain behaviors and decreases your likelihood of obtaining a hereditary disease)

Genes: Hereditary material on chromosomes that makes up DNA. Genes provide the blueprint for the production of cell proteins. The nucleus of the cell contains about 30,000 genes.

Genogram: A diagram outlining the history of the behavior patterns (as of divorce, abortion, or

suicide) of a family over several generations and it is also a diagram detailing the medical history of a family in order to assess a family member's risk of developing disease.

Using Scientific Method to Learn More about Nutrition 1. 2. 3. 4. 5. 6. 7. 8. 9.

Making observations, generating, and testing hypotheses Use of animal models versus humans in research Variety of research approaches Migrant studies Cohort studies Case control studies Follow-up study Double-blind studies Peer review of results and follow-up studies

Migrant studies: Look at changes in the health of people who move from one country to another

Cohort studies: The study of a group of people who share a common characteristic and move forward in time as a unit Case control studies: Complex observational studies with additional design features that allow us to gain a better understanding of factors that may influence disease

Double-blind studies: (Placebo: Fake treatment (e.g., a sham medicine, supplement, or procedure) that seems like the experimental treatment; used to disguise whether a study participant is in the experimental or control group.) (Placebo effect: Placebo is derived from the Latin word that means "I shall please." The placebo effect occurs when control group participants experience changes that cannot be explained by the action of the placebo they received. These changes may be linked to a treatment that is working, or a desire to help researchers achieve their goals. ●

Overall, it is critical for researchers to take the placebo effect into consideration when interpreting research results.)

Evaluating Nutritional Claims and Products 1. Are there inconsistencies with basic nutritional principles?

2. 3. 4. 5.

Are there dubious nutrition claims Scientific credentials of author, organization or publication Examine the study - the larger and longer the better Beware of 'hype' - does it survive testing

Buying Nutrition Products and Supplements 1....