Unit 1: An Overview Of Nutrition Flashcards
List some factors that govern the way we eat:
- Personal preference: Taste (sweet/salty/high fat), region (spicy peppers-Mexico; curry-south Asian), hormones of pregnancy
- Habit: Familiarity/comfort
- Ethnic heritage/tradition: cultural competence is important when helping others plan healthy diets
- Social Interactions
- Availability, convince, economy: accessible, quick, easy and within financial means
- Positive/Negative associations: associate food with activities/places. Using food as punishments/rewards may contribute to dislike/like
- Emotions: comfort (relieve boredom/depression), may contribute to obesity, sharing food during bereavement fulfills the givers need to comfort and the receivers need to be cared for
- Values: religious beliefs, political views, environmental concerns
- Body weight/image:decisions based on facts/knowledge can be helpful, decisions based on fads or extremes can be detrimental
- Nutrition/health benefits
Functional Foods are:
And include what?
Functional Foods: Foods that provide benefits beyond their nutrient contributions
Include:
Whole foods: Simple functional foods, natural (oatmeal, tomatoes)
Modified foods: Lowering fat content
Fortified foods: added nutrients/phytochemicals to provide health benefits (orange juice with added calcium)
List the 6 major nutrients
- Carbohydrates
- Lipids
- Proteins
- Vitamins
- Minerals
- Water
Energy-yielding nutrients:
Carbohydrates
Lipids
Proteins
Alcohol (but not considered a nutrient because it is not required)
Facilitate the release of energy from carbohydrates, lipids, and proteins and play a role in body processes:
Vitamins and minerals
Water
- 60% of adult’s body weight
- essential nutrient
- provides environment where nearly all body activities are conducted
Macronutrients
Required in large amounts (grams/litres)
- carbohydrates
- lipids
- protein
- water
Micronutrients
Required in small amounts (milligrams/micrograms)
- Vitamins
- Most minerals
Calorie
Units of energy
Kilocalories
1000 calories
Seen on food labels. When you see 100 Calories it actually means 100 Kcal
Kcal value of Carbohydrates
4kcal/g
Kcal value of lipids (fat)
9 (kcal/g)
Kcal value of protein
4 (kcal/g)
Kcal value of alcohol
7 (kcal/g)
1 kilocalorie (kcal) = 4.2 kilojoules (kJ)
1 kilocalorie (kcal) = 4.2 kilojoules (kJ)
Disciplines that contribute to nutrition
Biochemistry Physiology Anatomy Genetics Anthropology Psychology Sociology Religion Microbiology Agriculture Geography Business
Nutrition helps to:
- Explain the cause of disease (obesity, cancer, hypertension, diabetes, colon disease)
- Implications in public health policy
- Therapy
- Development of new food products
Food choices
Are modified/fortified foods more expensive? Are they worth it?
Do you buy foods that are promoted as better? Antioxidant-rich (blueberries, pomegranates), heart-healthy (almonds, walnuts)?
Nutrient Composition of the Body is similar to the composition of food
A healthy 70 kilogram (150 lb) body contains…
42 kg (90 lb) water
10-20 kg (20-45 lb) fat
Remaining kg are proteins, carbohydrates, major minerals of bones
Fraction of a kilogram is vitamins and minerals
Simplest nutrients are:
Minerals because they are a chemical element. All atoms are alike
Complex nutrients include:
Carbohydrates Lipids Proteins Vitamins Because they all have hydrogen, oxygen and carbon
Inorganic nutrients
Minerals and water
Include 1 atom or only hydrogen and water
Organic nutrients
Carbohydrates Lipids Proteins Vitamins Contain carbon
Essential Nutrients
Must be obtained from food because the body does not produce it or not enough of it
Most foods contain all 3 energy-yielding nutrients (carbs, lipids, proteins) as well as vitamins, minerals and other substances. What are the exceptions?
Sugar (pure carbohydrate)
Oil (pure fat)
Define Vitamin
- Organic but do not provide energy
- Facilitate the release of energy from carbohydrates, proteins, lipids
- Each of the 13 vitamins has a specific role to play (repair of blood cells/digestive tract/skin, protection, hormones
- Can only function if they are intact but since they are complex organic molecules they are vulnerable to destruction from heat, light, chemical agents
Define Minerals
- Found in structure arrays (bones/teeth)
- Found in the fluids of the body (Fluid balance/distribution)
- 16 essential minerals
- Inorganic and therefore indestructible
- Can be bound to other substances that inhibit absorption
Define Science of Nutrition:
Study of nutrients and other substances in food and the body’s handling of them.
Nutritional genomics-study of how nutrition affects the genes
4 components of Nutritional assessment
- Historical Information
- Anthropometric measurements
- Physical examinations
- Laboratory tests
Malnutrition
Deficiency or excess of nutrients/energy overtime
Undernutrition
Deficiency of energy
Thin, loss of muscle tissue, prone to infection/disease
Rashes, depression, hair loss, bleeding of gums, muscle spasms, night blindness etc.
Over-nutrition
Excess of energy
Obesity, heart disease, diabetes
Symptoms of malnutrition
Diarrhea
Rashes
Fatigue
(Easy to miss because they resemble symptoms of other diseases)
These symptoms could be the cause of malnutrition or just poor nutrition. Important to tell the difference
Define Nutrition Assessment of an Individual
Registered dietitian or other trained-health professional uses the 4 components. Each method involves collecting data in various ways and interpreting the findings in relation to the others to create a total picture.
Nutrition Assessment: Historical Information:
Person’s history in respect to:
- health status
- socioeconomic status (economics: ability to buy enough nutritious food, adequate facilities to prepare food) (social: marital status, ethnic background, educational level influence food choices/nutrition status)
- drug use (includes prescribed/over-the-counter may highlight possible interactions that lead to deficiencies)
- diet (intake of foods/beverages/supplements may indicate surplus or inadequacy of nutrients/energy)
- medical record (may reveal a disease that interferes with ability to eat/body’s ability to use nutrients)
- family’s medical history of major diseases (ex. Heart disease-genetic tendencies)
Diet History
Data of food a person eats over 24-hour or 3-day period or longer. (Food frequency questionnaires commonly used)
Accurate in food type and portion size
To find amount of nutrients consumed the assessor enters food and portion size into diet analysis program
Compares nutrient intake to DRI to determine probability of inadequacy
Nutritional Assessment: Anthropometric Measurements
Height
Weight
Compare measurements with standards for specific gender and age or with previous measurements from that individual
Periodic measurements reveal trends/patterns in nutrition status but provide little information on specific nutrients
May reveal problems in growth of children, wasting/sweeting of tissue, obesity
Energy/nutrient deficiencies or excesses
Nutritional Assessment: Physical Examinations
Visual inspection of hair, eyes, skin, posture, tongue and fingernails
Requires skill because physical signs can reflect more thane one nutrient deficiency/toxicity-or non-nutrition conditions
Does not yield firm conclusions but reveal possible imbalances (must be confirmed with other assessments)
What could an inflamed tongue represent?
Vitamin B deficiency
What could mottled teeth indicate?
Fluoride toxicity
Nutritional Assessment: Laboratory Tests
Blood, urine samples
Compare results with normal values for similar population
Uncover early signs of malnutrition before symptoms appear or confirm other assessments
Define Primary Deficency
Caused by inadequate diet
Assessment used: Diet History
Define Secondary Deficiency
Caused by problem inside the body
Assessment used: Health history
Define Subclinical Deficiency
Declining nutrient stores and abnormal functions inside the body (covert)
Assessment used: Laboratory Tests
List in order the stages of Development of a Nutritional Deficiency
- Primary Deficiency
- Secondary Deficiency
- Subclinical Deficiency and Covert symptoms (Inside the body)
- Physical Symptoms and signs (Overt) (Physical examination and anthropometric measures
Define Nutrition Assessment of Populations
Assess population’s nutritional status researchers conduct surveys similar to those used for individuals.
Used for development of national food and nutrition policies, programs and health goals
List the 4 methods of collecting diet information
- 24-hour food recall
- Food frequency questionnaire
- Food record/diary
- Diet history
Explain the 24-hour food recall
Interviewer asks subject to recall everything eaten/drunk in the previous 24-hours.
Food models/measurement aids are used to help estimate portion sizes
Used in many epidemiological studies where it is necessary to measure dietary intake
Explain a food frequency questionnaire
Used to rank how often a particular food/type of food is consumed in a specific time period day, week, month
Provides qualitative information on whether intake is high or low of a specific food group
Useful for quantitative nutrient intake (estimate portion size using models/measuring aids)
Used in epidemiological studies of dietary intake over extended period
Why are both the 24-hour food recall and the food frequency questionnaire prone to significant error?
Inaccuracy in people’s ability to accurately remember what they have been eating
Explain a food record/diary
Subject keeps record of food intake (indicating food, amount, method of preparation), may also need time of day consumed, with whom, where and how the subject is feeling. (May require weighing of food–but may cause subject to eat less). Studies show a 3-5 day record is as accurate as a 7 day record.
Explain Dietary History
Qualitative and quantitative information of long-standing food habits. Can reveal socioeconomic/cultural influences, intolerances, dislikes, seasonal variations, appetite/taste changes, physical disabilities (chewing, swallowing, motor skills, mobility), shopping/cooking practices, facilities of preparation/storage. Usually incorporated with another method. Is the most comprehensive of the 4 methods
Define food composition table
Diet information is collected and analyzed using a food composition table that list the average nutrient composition of foods
List some factors that influence the nutrient contents (nutrient values) in food composition tables
- Geographic location and season of production
- Mineral contents of the soil
- Stage of maturity at harvest
- The diet of animal or type of fertilizer used
- Method of processing
- Length and method of storage
- Cooking method
- Method of analysis
- Difference in water content of samples analyzed
Limitation of a food composition table (1)
Many trace minerals such as iodine and chromium are not included
Limitation of a food composition table (2)
Nutrient data is incomplete
Limitation of a food composition table (3)
Nutrient data is an approximation of actual food composition. Variation between food composition tables is unavoidable (too many influencing factors
Limitation of a food composition table (4)
The calculated amount of a nutrient in a given food should not be assumed to be completely absorbed by the body; certain factors enhance/inhibit absorption of nutrients. (Values listed only represent the amount the food contains)
Limitation of a food composition table (5)
Mixed dishes (soups, stews, casseroles) vary widely in nutrient composition depending on type and amount of ingredients used.
Limitation of a food composition table (6)
Legislation on enrichment/fortification varies between countries. (Minor variations exist between USA and Canada: vitamins A and D, folic acid, iron etc.)
Define Epidemiological studies:
Research the incidence, distribution and control of disease in a population. Includes cross-sectional, case-control and cohort studies.
List some strengths of epidemiological studies
- Can narrow down the list of possible causes
- Can raise questions to pursue through other research
List some limitations of epidemiological studies
- Cannot control variables that may influence the development or the prevention of a disease
- Cannot prove cause and effect
Define Experimental studies
Test cause-and-effect relationships between variables. Experimental studies include laboratory-based studies–on animals or in test tubes (in vitro)–and human intervention (or clinical) trials
List some strengths of experimental studies
- can control (most) conditions
- can determine effects of a variable
- can apply some findings on human beings to some groups of human beings
List some limitations of experimental studies
- cannot apply results from test tubes or animals to humans
- cannot generalize findings on human beings to all human beings
- cannot use certain treatments for clinical or ethical reasons
Explain DRI
Dietary Reference Intakes (DRI); a set of standards that define the amounts of energy, nutrients, and other dietary components and physical activity that best support health
