Midterm 1 Flashcards
What is the biggest determinant of what we eat
taste
What are the three macronutrients
carbs, fats, protein
What are the two micronutrients
vitamins and nutrients
Which of the micros are organic and which are inorganic
vitamins are organic, minerals are not
Are macros organic or inorganic
organic
What is the other component of food aside from macros and micros
water
How can you tell if something is organic
contains carbon
Which nutrient contains nitrogen
protein
How much energy (kcal/g) do carbs provide
4 kcal/g
How much energy do fats provide
9 kcal/g
How much energy do proteins provide
4 kcal/g
How much energy does alcohol provide
7 kcal/g
How do you calculate kcal of a food
for example; a food contains 45g of carbs, 5g of fat, and 10g of protein
- (45x4) + (5x9) + (10x4) = 265 kcal
How to calculate % energy from a given nutrient
for example; a food contains 45g of carbs, 5g of fat, and 10g of protein
- (45x4) + (5x9) + (10x4) = 265 kcal
% energy from carbs: (45x4) = 180 — 180/265 = 0.679 (x100) = 67.9% carbs
How many approx nutrients are essential
~40
What are some examples of essential nutrients
- amino acids
- water
- alpha-linoleic and linoleic acid
- vitamins
- minerals
- electrolytes
What does the body use the energy-yielding nutrients for
fuel: supports activity, and stored for later use
raw materials: building body tissues and regulating activity
How many vitamins are there
13
Which vitamins are water soluble
B and C
Which vitamins are fat soluble
A, D, E and K
How many mineral types are essential
16
What is the difference between vitamins and minerals
vitamins are organic, minerals are not
vitamins are destructible, minerals are indestructible
vitamins yield energy, minerals do not
What is the medium for all of lifes processes
water
What does DRI stand for
dietary references intakes
What is the DRI
guide for nutrition that provides a scientific basis for the development of food guidelines in US and Canada
What estimated percentage of the population is targeted by the estimated average requirements according to the DRI
EAR = 50% of the population
What estimated percentage of the population is targeted by the recommended dietary allowances according to the DRI
RDA = 98% of the population
What is the range of population targeted by average intakes
> 50% to <98%
What are the tolerable upper intake levels
the upper intake recommended for the average person
What does AMDR stand for
acceptable macronutrient distribution ranges (AMDR)
What are the 3 AMDR ranges
45-65% carbs
20-35% fats
10-35% protein
Compare the DRI and AMDR values for carbs
for example: DRI = 130g/d x 4kcal = 520 kcal/d
AMDR: 130g/d recommended (45%); 520/0.45 = 1155kcal/d
How do you calculate the dietary reference intake for an individual
ex. 20 yr old, 75 g, 175 cm with an EER of 2844 kcal/d
2844(45%) = 1279 (divide by 4 kcal/d) = 320 g/d
Why is AMDR unrealistic
doesn’t account for EER of an individual
What aspects of a plant based diet are beneficial
- eating more fibre-rich foods
- eating less red meat
- replacing foods that contain saturated fats with foods containing unsaturated fats
How large should a serving of protein be
1 palm
How large should a serving of fat be
1 thumb
How large should a serving of veggies be
1 fist
How large should a serving of carbs be
1 cupped hand
What is an important rule of thumb when picking fruits and veggies to eat
the more colour variety in the diet, the better!
What are examples of healthy carb options
quinoa, whole grains, wild rice
What are good protein food options
legumes, lean meats, lower fat dairy
What two numerical values are shown on food labels
absolute values and daily values
What are absolute values
the actual amount (usually in grams) of a nutrient within a food
What are daily values
the percentage of a nutrient in a food, based on the recommended amounts for a 2000 cal diet
List the changes made in food labels
- calorie values larger and bolded
- mg amounts shown
- updated list of minerals (potassium, calcium, and iron)
- serving size stands out more
- updated daily values
- new % daily value for sugars
- % daily value footnote
What does the nutrient claim “free” mean
contains none of
What does the nutrient claim “good source of” or “high in” mean
greater than 15% the daily value
What does the nutrient claim “less” mean
25% less of a nutrient compared to energy reference
What does the nutrient claim “light” mean
if not referring to something as “less”, then “light” must be specified (ie. light in texture)
What does the nutrient claim “organic” mean
95% or more of ingredients meet Canadian Organic Product Regulations
What are the 3 classes of health claims
disease risk reduction claims
function claims
general health claims
What is a disease risk reduction claim
well-established links between the food and disease risk reduction
What is a function claim
well-established benefit of consuming the food for biological health
What is a general health claim
provides dietary guidance to promote general health
Why are carbs important for a healthy diet
energy source
fibre
vitamins/minerals/phytochemicals
What are the three types of carbs
mono, di, and polysaccharides
What are examples of monosaccharides
glucose, galactose, fructose
What are examples of disaccharides
sucrose, maltose, lactose
What are polysaccharides made of
long chains of monosaccharides (usually glucose chains)
What is glucose important for
blood sugar
Where is fructose found
fruits and honey
Where is galactose found
natural dairy products
Which type of sugar is the sweetest
fructose
What makes up sucrose
glucose + fructose
What makes up maltose
glucose + glucose
What makes up lactose
glucose + galactose
What is glycogen
a polysaccharide that acts as the stored form of glucose in animals
- has highly branched chains
- reserves energy
What is starch
a polysaccharide that acts as the stored form of glucose in plants
- long branched and unchained chains
- found in grains, legumes, and root crops
What is fibre
the structural part of plants (different from starch)
- functional fibres
- resistant starches
- two types: soluble and insoluble
What are the three main health concerns of sugars
nutrient deficiencies
weight gain/diabetes
dental issues
What does Canada’s food guide say in relation to sugar intake
limit highly processed foods to reduce sugar intakes (no upper or lower limits, no numerical values)
What is the DRI for sugars
- no upper limit
- no more than 25% of daily energy intake
What is the WHO and FAO recommendation for sugars
- less than 10% of daily energy intake
- less than 5% is better
What are the health effects of soluble fibres
reduce risk of heart disease
reduce risk of diabetes
What are the health effects of insoluble fibres
alleviate constipation
lower risk of diverticulosis, hemorrhoids, and appendicitis
may help with weight management
What are the potential harmful effects of fibre
may limit the ability to meet other nutrition needs
may lead to: abdominal discomfort, gas, and diarrhea
What is the RDA for carbs
130g
What is the AMDR for carbs
45-65%
What is the recommended daily fibre intake
Health Canada daily value: 25g (for 2000 cal)
DRI: 14g per 1000 cal
What is the daily fibre intake limit
no real UL set
- WHO recommends no more than 40g
Why are fats important for diet
energy, cell growth support, immune function, nutrient absorption, production of important hormones
What three elements are fats made of
carbon, hydrogen, and oxygen
What are the three forms of fats
triglycerides, phospholipids, and sterols
What are examples of triglycerides
animal fats and olive oil
What’s an example of a phospholipid
lecithin
What are examples of sterols
cholesterol and plant sterols
What fatty acid chain length is most abundant in food
18-C fats
What is the difference between a monounsaturated fat and a polyunsaturated fat
mono = 1 double bond
poly = various double bonds (more unsaturated)
How many double bonds are found in stearic acid
0 (saturated)
How many double bonds are found in oleic acid
1 (monounsaturated)
How many double bonds are found in linoleic acid
2 (polyunsaturated)
How many double bonds are found in linolenic acid
3 (polyunsaturated)
Where are double bonds found on fatty acid chains
nearest the methyl end of the carbon chain
Which type of fatty acid is more stable (longer shelf life)
saturated
Which type of fatty acid is solid at room temp, vs which is liquid at room temp
solid = saturated
liquid = unsaturated
Which type of fatty acid type has shorter chain lengths
unsaturated
What is hydrogenation
when hydrogen atoms are added to unsaturated fats to make them saturated
- this is done to increase the shelf life of food, but it makes the food less healthy
What are trans fatty acids
derived from hydrogenation (altered unsaturated fatty acids)
What is the distinction between cis and trans fats
cis = hydrogens on same sides of double bond
trans = hydrogens on opposite sides of double bond
What is the major function of phospholipids
emulsifier
What is an example of a phospholipid
lecithin
What structure are sterols found in
ring structures
What is cholesterol
a sterol found in animals only
- made by the liver
- makes bile acids, hormones, and vitamin d
- makes up structural components of the cell
- plaque formation
What are plant sterols
sterols found in plants
- found at low levels in vegetables, fruits, nuts, and cereal grains
- inhibit cholesterol absorption
~150-360 mg/d (recommended 2g/d)
What are some health effects of lipids
heart disease: major risk factor = elevated blood cholesterol
- accumulates in arteries reducing blood flow
- can lead to stroke or heart attack
What are some risks from dietary fats
saturated fats, trans fats, and cholesterol: increased risk of heart disease
(unsaturated: decreased risk)
Where are saturated fats from
animal fats, processed foods, some vegetable oils (eg. pam, coconut)
Where are unsaturated fats from
vegetable oils, nuts, seeds, and fatty fish
What are the recommended intakes of fats
DRI and Canadas Food Guide: 25-30% of daily energy intake
daily values: 65g fat, 20g saturated, 300 mg cholesterol
daily: 30% TEI for total, 10% TEI for saturated
Canada’s Food Guide also says choose healthy fats instead of saturated
What are the AIs for linoleic and linolenic acids
5-10% TEI linoleic
0.6-1.2% TEI linolenic
Why are proteins important for the diet
building materials, hormones, enzymes, fluid balance, acid-base balance, transporters, antibodies, energy, blood clotting, and vision
How many amino acids are there, and how many are essential
20 total, 9 are essential
What 2 factors is protein quality determined by
digestibility and amino acid composition
How digestible is animal protein
90-99%
How digestible is soy and legume protein
greater than 90%
How digestible is plant protein
70-90%
Can we make “partial proteins”
no, we need all 9 essential amino acids from elsewhere because we cannot make partial proteins
What are complementary proteins
proteins that combine to create full amino acid compliment (ex. legumes and grains together)
What does PDCAAS stand for and what does it do
protein digestibility-corrected amino acid score
- measures protein quality on a scale of 0-100
What is the updated version of the PDCAAS
DIAAS (digestible indispensable amino acid score
What is protein-energy malnutrition
when one does not get enough protein or energy (or both combined) so they are deficient in protein energy
- most prevalent form of malnutrition worldwide*
What are the two forms of PEM
Marasmus and Kwashiorkor
What are the key indications of marasmus
deficiency in both protein and energy
- severe weight loss
- no edema
What are the key indications of kwashiorkor
deficiency in protein only
- some weight loss, but retains more fat than marasmus
- severe edema (swollen belly)
What infections can occur as a result of PEM
dysentery, anemia, heart failure, and in severe cases death
What factors can reverse PEM (in moderation)
rehydration, electrolyte balance, and gradual protein intakes
What are the two chemical level reasons we need protein
- amino acid intake
- nitrogen supply
What is the recommended AMDR for protein daily
10-35% dietary energy intake
What is the RDA for protein intake
0.8 g/kg body weight/day
What is Canadas Food Guide recommendation for protein
eat protein-rich foods daily, and choose proteins that come from plants more often
By what two movement processes does the small intestine break down food
peristalsis and segmentation
What three muscle types are found in the stomach
circular, longitudinal, and diagonal
What and where is the esophageal sphincter
found at the top of the esophagus
- opens in response to swallowing
What and where is the lower esophageal sphincter (cardiac sphincter)
bottom of the esophagus
- prevents acid reflex of stomach contents
What and where is the pyloric sphincter
bottom of stomach between stomach and small intestine
- holds chyme in stomach and prevents contents of the small intestine from going up into stomach
What and where is the ileocecal sphincter
found at end of small intestine
- allows for passing of contents to large intestine
What organ makes bile
liver
What organ stores bile
gallbladder
What organ is targeted by bile
small intestine
Where is salvia produced and used
the mouth
Where is gastric juice produced and used
the stomach
Where is pancreatic juice produced, and where is it used
produced in pancreas, used in small intestines
What part of gastric juice breaks down proteins
the hydrochloric acid denatures the proteins in the bolus
What macro does salivary amylase break down
carbs
What enzyme is found in gastric juice
pepsinogen
What is the order of digestion
mouth, salivary glands, stomach, small intestine, large intestine
What enzyme in the small intestine breaks down starch
pancreatic amylase
What enzymes in the large intestine break down fibre
bacterial enzymes
What two substances in the small intestine works to break down fats
bile and pancreatic lipase
Explain how fats are emulsified
enzymes work to combine bile and GI juices to create emulsified fat, otherwise known as micelles
What substance in the stomach works to break down proteins
pepsin
What substances break down proteins in the small intestine
pancreatic and intestinal proteases, as well as tripeptidases and dipeptidases
How long after eating does the body absorb nutrients
3-4 hours
Where does the majority of absorption take place
the small intestine
What is the hepatic system
the blood flow system throughout the body
How is excess glucose stored in the body
stored as glycogen in the liver
What are chylomicrons
clusters of proteins and lipids, that are used as transport vehicles for lipoproteins
What are the 4 types of lipoprotein in descending order from largest to smallest
chylomicrons (least dense), VLDL, LDL, HDL (most dense)
What are chylomicrons mainly consisting of
triglycerides
What are HDL mostly consisting of
protein
Which lipoprotein has the highest cholesterol content
LDL
Which lipoprotein is “good” cholesterol
HDL
Which lipoprotein is “bad” cholesterol
LDL
Where is HDL made
the liver
What factors lower LDL and increase HDL
physical activity, moderate alcohol consumption, phytochemicals, less saturated fats, soluble dietary fibres, weight control, etc.
What is lipoprotein lipase
the enzyme that breaks down lipoproteins - activated by insulin
Where are lipoprotein lipases located
on an endothelial cell lining the capillaries
Where are amino acids sent
intestinal cells
Where are unused amino acids sent
liver via bloodstream - then transported to other organs to create new proteins
What happens to amino acids that are not used at all
cannot be stored, therefore excreted (deamination creates ammonia, which is converted to urea and excreted)
What is the “final stage” of digestion
vitamins and minerals absorbed
any undigested residues continue in GI tract
fibre fermentation occurs in the large intestine via bacteria
Is it true that people should eat specific food combinations within a meal because the digestive system should not be overridden
no, that is not true
Where is first pass clearance in the hepatic system
the liver
Blood travels from the digestive tract via the ___________ __________ ______ to the liver
hepatic portal vein
Blood leaving the heart goes to the liver via the _______ _______
hepatic vein
What are some important functions of the liver
storage
bile production
detoxification
produce hormones
produce blood clotting factors
produce transferrin
produce glucose and ketone bodies
What two components go to the liver
monosaccharides and amino acids
How do fats bypass first pass clearance
by travelling through lymph
