Nutrition Flashcards
(181 cards)
1
Q
What three actors influence nutrition
A
Environment (food)
Agent (diet)
Host (Body)
2
Q
Burden of disease from poor nutrition
A
2 in 5 deaths
3
Q
NZ obesity
A
~1/3 adults
Child obesity very high
4
Q
Rationale for Eating Statement 1 “Variety of nutritious foods”
A
Need lots of different nutrients which you can only get from lots of different sources
5
Q
Why are fruits and vegetables important
A
Vitamins C A K
Minerals
Fibre
6
Q
Why wholegrains
A
Bran and germ contain FAR more nutrients/vitamins/fibre than the endosperm
7
Q
Why dairy important
A
Calcium
Vit A K
Protein
8
Q
Why legumes, nuts, fish, meat important
A
Protein
Iron and Zinc
Vitamin A, E
Fatty Acids
9
Q
Where do NZers consume too much salt
A
Processed foods
Bread as despite moderate amount of sodium, it is eaten frequently in NZ
10
Q
Why is eating statement 2 “Minimal sat fat, sugar, salt” important
A
These do bad things
Sat fat - obesity, cardiovascular
Salt - cardiovascular, renal
Sugar - cardiovascular, diabetes
11
Q
Why is eating statement 3 “Water main drink” important
A
Water doesnt have high sugar etc
Hydration for renal
12
Q
Why is eating statement 4 “Low alcohol” important
A
Alcohol bad for liver, cardiovascular
13
Q
Why is eating statement 5 “store food safe way” important
A
Dont want bacterial infections from undercooking etc
14
Q
Why are population guidelines and individuals different
A
Individual goals need to factor in cost, taste, culture, marketing etc
Specific goals eg Coelaic no wheat even though wholegrain wheat would be recommended for most people
15
Q
Who is most at risk of malnourishment
A
Low SES
Elderly - can’t swallow all food types, harder to cook well etc
16
Q
What are the two ways of taking a nutrition assessment
A
Habitual
Time-period
17
Q
What is a time-period nutrition assessment
A
Intake in a specific time eg last 24 hrs
18
Q
What is a habitual nutrition assessment
A
Standard intake, not based on any particular day
19
Q
ABCDE of Nutrition Intake
A
Anthropometry
Biochemical
Clinical
Dietary
Economic / social
20
Q
Anthropometry Things to check
A
The delta - weight, height, body composition changes including rate of chnage
Weight
Height
Circumferences - waist adults
- mid-upper arm children
21
Q
Measuring body composition measures
A
Fatfold
Hydro density entry
DEXA
Bio electrical impedance
Air displacement
22
Q
Drawback to fatfold body composition method
A
Assumes subcutaneous fat is proportional to total fat
23
Q
Drawback to DEXA
A
Accurate but expensive
24
Q
Drawback to hydrodensitometry
A
Estimate using volume calculations
25
BMI calculation
Weight / height-squared
26
Normal BMI
18.5-24.99
27
Obese BMI
Over 30
28
Different ethnic groups have different healthy BMI ranges?
Yes
- Asians lower
- Maori higher
29
When does change in body weight become significant
>5.0% in 3 months
KEY POINT IS TIME INVOLVED
30
Biochemistry nutrition assessment
Blood and urine tests to check nutrients
31
Clinical Biochemical assessment
Signs/symptoms of deficiency/toxicity from physical examination
Oral and dental health
Medications
32
Where can you check malnourishment using fat
Pinching biceps region
- If no fat tissue = severe malnourishment
- If little fat = mild malnourishment
33
Dietary nutrition assessment
Estimation of dietary requirements and whether they’re being met
- Food and beverage intake
- Patterns of intake
- Supplements
- Food insecurity
34
Why are nutrition assessments important / used for
Malnourishment = high burden of disease
Used for determining if malnourished, making treatment plans, evaluating current interventions etc
35
What is the main source of energy for all ethnicities
Carbohydrates
- But different types eg potatoes Irish, Native American corn
36
Two principal types of carbohydrates
Complex or simple
37
Complex carbohydrates
Starches and fibre
38
Simple carbohydrates
Sugars (Di/monosaccharides)
39
Fructose
Monosaccharide from fruit
40
Galactose
Monosaccharide from dairy
41
Glucose
Monosaccharide that is rarely directly eaten, but made from conversion of other saccharides
42
Sucrose
Disaccharide that is “table sugar” ie main added sugar!
43
Lactose
Disaccharide dairy
44
Maltose
Disaccharide from fermentation (alcohol)
45
How are carbohydrates stored
Polysaccharides
- Glycogen = main human
- Starches = main plant, not made by us but consumed
46
Carbohydrate DIgestion in oral cavity
Mechanical - teeth
Chemical - salivary amylase breaks down starch
47
Carbohydrate digestion in stomach
None! As acidity deactivates amylase
48
Chemical Digestion in Small Intestine (Carbohdrates)
Pancreatic Amylase = further breaks down into small polysaccharides
Disaccharides ——> monosaccharide + glucose
X-ase (enzyme always X-ase eg sucrase acts on sucrose -> fructose)
49
Absorption of glucose
Active (Primary/secondary)
50
Absorption of fructose
Facilitated diffusion
51
Absorption of galactose
Secondary active
52
Fibre benefit
Protects against colorectal cancer, and other bowel health
53
How Microbiome impacted by nutrition
Specific nutrients associated with specific microbes = good gut
54
High glycaemic index carbs
Rapid rise in blood glucose / insulin in short-term
- Worse for diabetes
- Makes you hungry again soon
55
Examples of high glycaemic index carbs
Added sugar eg coke
Fruit (but fruit still healthy therefore not all high glycaemic bad)
56
Low glycaemic index carbs
Lower glucose and insulin spread over long time
- Better for diabetes
- Less hungry soon
57
Vit B12 Structure
Corrinoid ring (4 pyrolle rings)
58
Change to B12 (Cbl) in stomach
Binds to HC
=HC-Cbl
59
Change to B12 (Cbl) in duodenum
HC cleaved by pancreatic enzymes
Now can bind to IF
= Cbl-IF
60
Change to b12 (Cbl) in ilium
Absorbed
61
Types of B12
HC-Cbl = inactive, stored in liver
TC-Cbl = active, used in all cells
62
Deficiency of B12 results in
Macrosytic anaemia (pernicious aneamia)
63
Main cause of B12 deficiency
Lack of IF (required for absorption), rather than direct lack of B12
64
B12 dietary sources
Meat and animal products
65
People at risk of B12 deficiency
Vegans
- Vege fine since eggs, milk as well as meat
66
Requirements for B12 to bind to IF
R-binders
Panc enzymes
67
Pernicious Anaeamia
Autoimmune attack of parietal cells = not enough IF = not enough B12 = macrocytic aneamia
68
Pernicious Anemia Detetction
Autoantibodies of parietal cells
Other autoimmune conditions (as autoimmune conditions rarely isolated to just one)
69
Treatment of B12 malabsorption
Intramuscular injection
70
Schilling’s Test
1. Radioactive B12 + INJECTION of B12 = saturated B12 = would expect in urine if normal
2. Radioactive B12 + SWALLOW of B12 = saturated B12 = would expect in urine if problem is making=stomach, not in urine means absorption problem=ilium
71
What do proteins do
Energy
- Only when carbohydrate not sufficient
Enzymes, ion channels, transport, immune, structure etc
72
Essential Amino Acids number
9
73
Conditionally essential amino acid
Cant make in sufficient quantities under certain conditions therefore becomes essential
74
Non-essential amino acid
Synthesised by our body = dont need dietary intake
75
Protein percentage of energy intake
15-25%
76
Women recommended grams of protein per kilo per dag
0.75 g/kg/d
77
Men recommended grams of protein per kilo per day
0.84g/kg/d
78
Why do you need to do exercise to make protein intake help build muscle mass
If not then excess protein = excreted via urine
79
Are protein supplements useful
For most people no, only if malnourished or if intense exercise
80
Supplement important questions to ask
Safe
Legal
Batch tested
Work for me specifically
81
What is a complete protein
Has all/most of the essential amino acids
Animal proteins are more complete than plant
82
What are complementary proteins
Together they form a complete protein and have all/most essential amino acids
83
Protein Digestion pre-stomach
1 Cooking denatures protein
2 Mechanical digestion mouth
Moistened saliva
84
Protein digestion stomach
Pepsin (pepsinogen -> pepsin by HCl) breaks polypeptide into di/tri peptides
85
Protein digestion small intenstine
Broken into individual amino acids by pancreatic enzymes (trypsin, chymotrypsin, carboxypeptidase)
86
Tyypsinogen -> trypsin enzyme
Enteropeptidase
87
Chymotypsinogen -> chymotripsin enzyme
Trypsin
88
Procarboxypeptidase -> carboxypeptidase enzyme
Trypsin
89
What do trypsin, chymotrypsin, and carboxypeptidase do
Break di/tripeptides into individual amino acids = can be absorbed
90
Amino acid absorption small intestine method
Primary/secondary active into enterocyte
Fac diff into blood
91
What byproduct is produced during protein breakdown
Ammonia
92
How do we remove excess ammonia
Excretion urine
93
Positive nitrogen balance
Intake > exposure
= Growth
94
(Neutral) nitrogen balance
Intake = expenditure
Healthy adult that is not growing, pregnant etc
95
Negative nitrogen balance
Expenditure > intake
Starvation, cancer, burns etc
96
Nitrogen intake calculation
g(N) x 6.25 = g(Protein)
97
Calaculation for nitrogen balance
Grams excreted via urine sample
Grams intook via dietary measure of protein, then divide by 6.25
See if equal
98
Kwashiorkor
Diet deficient in protein (but sufficient energy)
= Muscle wasting, but preserved subcutaneous fat
99
Marasmus
Diet deficient in protein AND energy
= Severe muscle wasting, loss of subcutaneous fat as well
100
Most energy dense macronutrient
Fat (37 kJ/g)
101
Where do you get plant fats
Nuts and seeds
102
Short chain fatty acid length
1 to 6 C
Eg milk
103
How do trans fats occur
Not in nature, only byproduct of manufacturing
104
Saturated fats characteristics
Solid at room temp
Hard to spoil
Bad for heart
105
Unsaturated fats characteristics
Polyunsaturated liquid at room temp
Spoil more readily (unless hydrogenated = trans fat)
106
Essential fatty acids
Omega 3 and Omega 6
107
Omega 6 pro/anti inflammatory
Pro (which is good as we need ability to do acute inflammation)
108
Omega 3 pro/antiinflammatory
Anti (= good)
109
Why is the ratio of omega 3 and 6 important
They compete for the same enzymes to be converted into final form = important to ensure we are not saturating the enzymes with just one type
110
Final product of omega 3 and omega 6 conversion
Eicosanoids (direct cell action, not hormone)
111
Omega 6 conversion pathway
LA (vege oil) -> gammaLA -> AA (animal) -> eicosanoid
112
Omega 3 conversion pathway
ALA(veg oil) -> EPA (fish) -> DHA (fish) -> eicosanoid
113
Why do we need omega 3 and 6
Brain development
Vision
Inflammatory pathways
114
Do we need more omega 3 or omega 6
Absolute - omega 6
In NZ - more omega 3 to improve ratio
115
Ideal omega 3 to 6 ratio
1 Omega-3 : 2-4 Omega-6
116
Are sterols endogenous or exogenous
Both endogenous from production in our liver, exogenous from fish eggs and plants
117
Fat digestion in mouth
Mechanical
Release of lingual lipase (doesn’t do anything until pH activation)
118
Fat digestion stomach
Lingual lipase activated by pH
Gastric lipase
Muscle contractions disperse fat into smaller droplets
119
Fat digestion small intestine
Bile emulsifies fat into micelles
Pancreatic enzymes break emulsified fats down into monosaccharides, glycerol, fatty acids
120
If removed gall bladder how should you change your diet
No gallbladder = cant store bile, but can still produce
Therefore have smaller biles more often, and decrease fat intake
121
Why can micelles be absorbed but larger fat cant
Micelles small = sufficiently water soluble
122
What transports exogenous lipid
Chylamicrons CM
123
Endogenous lipid transported by
VLDL Very low density lipoprotein
124
What happens to CM when travelling around body
Shrinks in size and then eventually reabsorbed
125
Desired Energy intake from fat
20-35% total
trans/sat should be <10%
126
How is iron stored in the body
Ferrotin
127
Iron used in
Haemoglobin/myoglobin
Cytochrome P450 - metabolism of fatty acids
128
Iron transported in blood via
Transferrin
129
Iron absorbed where
Duodenum and proximal Jejunum
130
Can iron be excreted
Not easily - only by shedding intestinal cells that have iron stored as ferrotin
131
Iron in plants is
Only Nonheme
132
Iron from meat is
Heme and nonheme
133
How is heme iron absorbed
HCP1 into cell
Hox1 out of heme into Fe2+
134
How is nonheme iron absorbed
1. Reduced to Fe2+ by DRA and Dcytb (in lumen)
2. Absorbed by Dcytb and DMT1
135
How does iron get from absorptive cell into blood
Ferroportin channel (then into transferrin for transport)
136
Hepcidin function
Inactivates ferroportin = iron stuck in gut and can’t get to blood
137
Factors that enhance nonheme iron absorption
Vitamin C
Acid
MFP (in meat)
138
Factors that inhibit nonheme absorption
Phytates - bran
Tannins - tea
139
Dietary sources of iron
Meat, spinach etc
Contamination from cookware
Supplements
Fortification - cereal!
140
Who needs high iron
Women
Especially pregnant women
Growing children
141
Type of anaemic from iron deficiency
Microcytic
142
Stages of iron deficiency
1. Depleted storage
2. Iron restricted erythropoiesis
3. Iron deficiency anaemia
143
Most common nutrient deficiency globally
Iron
144
What is the RDI
Level considered adequate to meet the needs of almost all healthy individuals (ie well above the estimated average requirement)
145
Water voluble vitamins
B and C
146
Fat soluble vitamins
ADEK
147
Excretion of fat/water soluble vitamins
Water - easy excretion via urine
Fats - less ready excretion, stored in fat
148
Absorption of water/fat soluble vitamins
Water - direct to blood
Fat - lymph then blood
149
Factors that affect Bioavailability of vitamins
Effieicny of digestion
Other foods consumed simultaneously
Food preparation method
Nutritional status
Synthetic/natural source
150
Vitamin B1 other name
Thiamine
151
Thiamine absorption site
Duodenum
152
Thiamine transport method
Active
153
Thiamine transport inhibitor
Alcohol
154
Thiamine sources
Whole grain - bran and germ which is removed in refined grains
155
Beriberi meaning
Thiamine deficiency
156
Wet beriberi impact
Heart failure
157
Wet beriberi chronic/acute
Acute
158
Dry beriberi acute/chronic
Chronic
159
Dry beriberi impact
Muscle wasting / neurological
160
Main cause of thiamine deficiency in developed countries
Alcoholism as transport inhibited
- Maybe we should supplement alcohol with thiamine
161
Vitamin B9 synonym
Folate
162
Folate function
Nucleic acid production and heart health
163
Cause of folate deficiency
High alcohol
Anti-inflammatory drugs
PREGNANCY
164
Why should we fortify with folate for everyone even though normally just when pregnant that defient
So much development happens before you know you’re pregant
165
Impacys of folate deficiency
Neural tube defects
Macrocytic anaemia
166
Vitamin D dietary source
Oily fish
167
VItamin D our own synthesis
Skin needs UV to convert to active form
168
Vitamin D function
Maintain plasma concentration of calcium to lead to increased bone density
169
Vitamin D deficiency impact child
Rickets
170
Vitamin D defiency impacy adult
Osteomalacia
171
Who needs Vit D supplement
People who have had bone injury eg surgery, trauma as increased metabolic demand
Drug-nutrient interactions
172
How long should you breastfeed
Exclusively 6 months
Continue for 2 years (or longer)
173
If adequate nutrition what changes during a babies first year
Massive weight increase
Length, head circumference, brain increase
174
Food security requires
Physical, social and economic access to nutritious and safe food
175
Low birth weight, or low growth as a child is associated with
Non communicable diseases later in life
176
Baby energy intake per kg compared to adult
Greater energy per kg needed
177
Why do people stop breastfeeding too early
1. Back at work
2. Social norms
178
Baby desired renal solute load
Low mOsm/L
Therefore breast milk is good, and better than formula
179
What nutrient do babies need the most
Iron
180
Which food groups are children lacking the most in
Fruit and veg
181
How should we compact childhood obesity
Dietary recommendations, physical activity
EARLY INTERVENTION - before school check
