HUBI 2002 Midterm 1 Flashcards
Nutrition
Study of how food nourishes the body
Food
Any substance the body can take in and assimilate; source of nutrients
Malnutrition
Lack of proper nutrition; nutrient deficiencies, nutrient imbalances, nutrient excesses
Genome
full component of genetic material in the chromosome of a cell
DNA
molecule that encodes genetic info in its structure
Nutritional genomics
science of how nutrients affect the activities of genes and how genes affect the interactions between diet and disease
Energy
capacity to do work; measured in cal or kJ
Nutrients
components in food the body needs to grow, develop, and repair itself
energy yielding nutrients
Carbs, fats, proteins
6 Categories of nutrients
- Carbs
- Proteins
- Fats
- Vitamins
- Minerals
- Water
Essential nutrients
nutrients the body cannot manufacture for itself and must obtain from food
Calories
unit of energy produced by food and used by the body; amount of heat energy needed to raise the temp of 1kg of water 1 degree C
Joules / kJ
Unit of E. 100kcal=418kJ. Defines both kinetic and chemical energy
Carb and protein energy yield
4kcal/g
Fat energy yield
9 kcal/g
Elemental diets
Diets composed of purified ingredients of known chemical composition; intended to supply all essential nutrients to people who cannot eat foods
Non-nutrients
compounds in foods, other than the six nutrients, that have biological activity in the body
Phytochemical
non-nutrient compounds that confer colour, taste, and other characteristics of food
Basic foods
foods which nutrients have been added; milk, meats, veggies, fortified and enriched foods
Fast foods
restaurant food that is ready to serve before orders are taken
Functional foods
claims to have nutrients that fights disease
Natural foods
wholesome foods
Nutraceuticals
foods designed to act like drugs
Organic foods
foods grown without synthetic pesticides or fertilizers
Partitioned foods
made from components extracted from whole foods; milling, alternation of texture or addition of additives
Staple foods
foods used frequently or daily
ABCMV principles
Adequacy, balance, calorie control, moderation, variety; help recognize a nutritious diet
Adequacy
providing all the essential nutrients, fiber, and E in amounts sufficient to maintain health
Balance
dietary characteristic of proving goods of a number of different types in proportion to each other such as foods rich in some nutrients don’t replace foods that are rich in others
Calorie control
Control of E intake
Moderation
set limits; nothing in excess
Variety
a number of different kinds; adds interest
Nutritional monitoring
assessment of dietary or nutritional status at intermittent times with the aim of detecting changes in the dietary or nutritional status of a population
Canadian Community Health Survey (CCHS)
cross sectional survey study of people over 12yrs, started in 2004, now conducted every 2 years. Self reported info on health status and eating habits of a sample (65000 Canadians per study)
The scientific method
A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions
Epidemiological study and case study data
correlation
Intervention study data
cause and effect
lab study data
cause and effect in an animal model
Blind experiment
subjects do not know whether they are members of experimental or control group
Case studies
studies of an individual
Control group
Group that does not receive the experimental treatment
Correlation
a measure of the relationship between two variables
Epidemiological studies
Studies of populations
Experimental studies
investigation
Intervention studies
studies of populations in which observation is accompanied by experimental manipulation of some population memebers
Lab studies
studies are performed under tightly controlled conditions and are designed to pinpoint causes and effects
Placebo
A fake drug used in testing of medication
Randomized controlled trial (RCT)
clinical trials
DRI
Dietary reference intake; a set of 5 nutrient intake values for healthy people in Can and USA
Goals of DRI committee
- establish recommended intake values
- facilitate nutrition research and policy
- establish safety guidelines
- prevent chronic diseases
RDA
Recommended daily allowance; nutrient intake goals for individuals
AI
Adequate intake; nutrient intake goals for individuals are set whenever scientific data are insufficient to allow establishment of the RDA value
EDA
Estimated average requirement; data driven
UL
tolerable upper intake level; the max daily amount of a nutrient that appears safe for most healthy people and beyond which there is an increased risk of adverse health effects
CDRR
Chronic disease risk reduction; new DRI category based on chronic disease risk
AMDR
Acceptable macronutrient distribution range; values for carbs, fat, and protein as percentages of total caloric intake
DV
Daily value; nutrient reference standards used on food labels in grocery stores
Percent daily value
A vaue that shows how the nutritional content of one serving of food fits into the diet of a person who consumes 2000 calories a day
Nutrition facts table
mandatory since 2007 on all food products. Required to list calories and 13 core nutrients
Serving size
amount of food item customarily eaten at one time
Discretionary calorie allowance
difference between calories needed to maintain weight and those needed to supply nutrients from the most nutrient-dense foods
Nutrient density
A measure of the nutrients a food provides relative to the E it provides. The more nutrients and the fewer kcal, the higher the nutrient density
5 basic chemical tastes
- Sweet
- Sour
- Bitter
- Salty
- Umami
Digestive tract
flexible, muscular tube that digests food and absorbs its nutrients and some non0nutrients
Chewing and swallowing
Teeth tear and grind food into small pieces
Salivary glands produce saliva
Enzymes in saliva begin chemical breakdown
Epiglottis closes off trachea
Food moves down esophagus
Mechanical digestion
Physical breakdown of food
Chemical digestion
Enzymes break down food into smaller molecules
Protein digestion
Begins in the stomach; gastric juices required to break it down
Small intestine
digestive organ where most chemical digestion and absorption of food takes place
Absorption and transportation
shipping
absorbs nutrients into body fluids
Nutrients are delivered to necessary systems
Large intestine
last section of digestive system, where water is absorbed from food and the remaining material is eliminated from the body
Eating and drinking too fast
hiccups and choking
Eating and drinking too much
Heartburn, GERD
3 types of fatty acids
Saturated
Monounsaturated
Polyunsaturated
Saturated fats
a fat solid at RT and found in animal fats, lards, and dairy products
Unsaturated fats
liquid at RT and found in vegetable oils, nuts, and seeds
Fat or lipid
class of naturally occuring organic cmpds which are generically hydrophobic in nature; fatty acids, triacylglycerides, sterols and phospholipids
Fatty acids
Carboxylic acid consisting of a hydrocarbon chain; common length C4-C8
Triglycerides
Most abundant dietary lipid, consists of 3 fatty acids and 1 glycerol molecule
Phospholipids
amphipathic and major lipid found in biological membranes; consists of 2 fatty acids
Sterols
amphipathic lipid with hydroxyl groups (alcohol); 4 ring structure
Essential fatty acids
Omega 3 and omega 6
Omega-3 fatty acids
Polyunsaturated fatty acids commonly found in fish oils that are beneficial to cardiovascular health
Omega-6
Linoleic acid - found in seeds, nuts, vegetable oils
EPA and DHA
eicosapentaenoic acid,
docosahexaenoic acid;
omega-3 fatty acids made from linolenic acids in the tissues of fish (non-essential)
LDL cholesterol
“bad” blood cholesterol; delivers plaque to the arterial walls; <100 mg/dl
HDL cholesterol
good; high density lipoprotein. High protein, low fat
Protein
A three dimensional polymer made of monomers of amino acids. 20 Amino acids included (9 being essential)
3 strands of amino acids
Chain
Coil of strand
Folding of strand
Protein turnover
process of continuous breakdown and synthesis of protein from its amino acids
9 essential amino acids
Histidine
Isoleucine
Leucine
lysine
methionine
phenylalanine
threonine
tryptophan
valine
Protein quality
a measure of the presence and digestibility of the essential amino acids in a feedstuff
High quality protein
dietary proteins containing all the essential amino acids in relatively the same amounts that human beings require
Low quality protein
dietary proteins that are low in or lack one or more essential amino acids (plant foods)
First limiting amino acid
the amino acid present in the diet in the least amount, in relation to the animals need for that specific amino acid
How much protein do we need?
0.8g/kg of protein by body weight / day
Females protein rda
46g/d, typically take 65g/d
Males protein rda
56g/d, typically take 105g/d
Omnivore
an animal that eats both plants and animals
Lacto-ovo-vegetarian
person who consumes all vegan items plus dairy products and eggs
Lacto-vegetarian
excludes animal flesh and eggs but does include dairy products
Fruititarion
raw or dried fruits and nuts only
macrobiotic diet
a vegan diet composed mostly of whole grains, beans, and certain vegetables; taken to extreme, macrobiotic diets can compromise nutrient status
ovo-vegetarian
person who consumes all vegan food items plus eggs
partial vegetarian
no red meat or limited quantities
Pesco-vegetarian
eliminates poultry and red meats
Vegan
a person who does not eat food from any animal source
Vegetarian
a person who eats mostly or only plant-based foods
Carbohydrates
organic compounds composed of C, H, and O in a ratio of about 1 C to 2 H to 1 O
Monosaccharides
glucose, fructose, galactose
Disaccharides
lactose, maltose, sucrose
Starch
plant storage form of glucose; packed in granules
Glycogen
storage form of glucose in humans and animals
Starch composition
amylose (unbranched)
Amylodpectin (branched)
Carbohydrate digestion
Starts in mouth with amylase converting polysaccharides to disaccharides, continues with pancreatic amylase, finished with sucrase/maltase/lactase from small intestine converting disaccharides to monosaccharides
Good carbohydrate sources
whole grains, low fat unsweetened protein foods and lean meats
Total carbs
WHO; 55-75% of diet
Wheat kernel
Germ, endosperm, bran, and husk
Dietary fibre
refers to the foodstuffs that have not been digested on entering the large intestine
Fibre recommendations
WHO: more than 25g daily
Benefits of fibre
reduces risk of heart disease, diabetes, and bowel disease
promotes healthy body weight
Preventative benefits of fibre
constipation, hemorrhoids, appendicitis, diverticulois and colon cancers
Obligatory glucose users
brain, nervous system and red blood cells
Breakdown of glucose
broken in half, broken into smaller units (irreversible; 2 pathways)
Release of insulin
rise of BG
Release of glucagon
drop in BG
Storing glucose for energy
brain, muscles, and liver store glycogen. Muscles conserve for own use, liver in generous with it
Excess glucose
converted to glycogen or fat and stores
glycemic response
how quickly and how high blood glucose rises after carbs are consumed
