Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Life Maintenance > Nutrition > Flashcards

Nutrition Flashcards

1
Q

What is nutrition?

A 
sum of processes involving:
- growth 
- maintenance 
-repair
of the body as a whole or its constituent parts

“effects of food on the body in health and disease”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What 6 main processes are involved in proper nutrition?

A 
ingestion
digestions
absorption 
transport
assimilation
excretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is diet?

A

sum of food consumed by a person

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between food and nutrients?

A 
Food = substances we take into our body. Classified into groups
Nutrient = components of food
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the types of macronutrients?

A

Fat
Carbohydrates
Protein
Alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the types of micronutrients?

A

Vitamins (water- vs fat-soluble)

Trace minerals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which vitamins are water soluble?

A

Vitamin B and C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which vitamins are fat-soluble?

A

Vitamins A, D, E, K

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many calories do each of the macronutrients carry?

A

Fat: 9 kcal/g
Carbs: 4 kcal/g
Protein: 4 kcal/g
EtOH: 7 kcal/g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is nutrition important?

A

prevent deficiency and disease

safeguard against toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How are nutrient requirements calculated?

A

Observational: average intake amongst healthy groups
Experimental:
- vary nutrient intake and estimate minimum amount needed to prevent deficiency
- identify biochemical markers to detect depletion of nutrient stores prior to presentation of symptomatic deficiency (e.g. ferritin as a proxy for iron)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is ferritin used as a maker of nutrient status?

A

iron stored as ferritin
small amounts of ferritin secreted into plasma
serum [ferritin] correlates with size of total body iron stores
low serum ferritin = depleted iron stores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the caveat when using ferritin as a marker of iron stores?

A

Ferritin = +ve acute phase protein
[ferritin] increase during inflammation
It is then no longer an accurate estimation of the iron stores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is total energy expenditure?

A

= basal metabolic rate + diet-induced thermogenesis + activity ± stress

where stress = illness ± inflammation ± surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is total energy expenditure measured?

A

direct or indirect calorimetry

usually in research

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is total energy expenditure estimated in the clinical situation?

A

use predictive equations and adjust for clinical situation

  • 23-35 kcal/kg
  • Schofield equations
  • Harris-Benedict equation
  • Ireton Jones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What affects nutrient requirements?

A 
age 
gender
body size
physical activity
state of health 
physiological status (e.g. pregnancy and lactation)
growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are dietary reference values (DRV)?

A

estimates of the amount of energy and nutrients needed by different groups of HEALTHY people in UK population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which situations are dietary reference values irrelevant?

A

in individuals
in illness/injury
outside UK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which regulatory bodies generate dietary reference values?

A

was COMA

now superseded by SACN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the different types of DRVs?

A 
EAR = estimated average requirement 
RNI = reference nutrient intake
LRNI = lower reference nutrient intake 
SI = safe intake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is RNI calculated?

A

reference nutrient intake (RNI)

= amount of that nutrient that is sufficient for 97.5% of the group or population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How is LRNI calculated?

A

lower reference nutrient intake (LRNI)
= amount of nutrient that is enough for only 2.5% (lower) of a group
i.e. the majority of people need more than LRNI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is EAR calculated?

A

estimated average requirement (EAR)
= intake level for a nutrient at which 50% of the group/population will be met
this means that 50% will need less than the EAR
and 50% will need more than the EAR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which DRV is used as a measure of energy intake?

A

EAR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which DRV is used as a measure for protein, vitamin and mineral intake?

A

RNI

Also used as a reference amount for population groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is LRNI a useful measure of?

A

nutritional inadequacy

i.e. the amount(s) at which deficiency or symptoms may appear as intake is too low for that nutrient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Why do we estimate nutritional requirements?

A

Benchmark to evaluate dietary adequacy/demands in HEALTHY GROUPS

Plan what to provide - hospital menus, school meals, rations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How can DRVs be used in clinical situations?

A

Can distinguish underlying pathology from a low intake of a nutrient
e.g. if intake > RNI, deficiency is unlikely to be due to inadequate intake
BUT if intake < LRNI, then they are not consuming enough of that nutrient to meet their requirements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the main caveats of using DRVs?

A
  • Bioavailability of nutrient
  • assumes that requirements for other nutrients are met (i.e. cannot look at multiple nutrients at once)
  • DRVs have differences between countries
  • DRVs reflect needs of healthy people not unwell people
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Why do deficiencies develop?

A
  • inadequate intake
  • reduced absorption (e.g. Coeliac)
  • increased losses (e.g. D+V)
  • increased demand (e.g. pregnancy)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the stages of nutrient deficiency?

A 
= supply < demand
Stages:
- health 
- subclinical deficiency 
- deficiency 
- death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the main symptoms of vitamin A excess?

A

toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the main features of vitamin A deficiency?

A 
LEAST DEFICIENT
Health
Depleted vitamin A stores in liver 
Low blood levels
Increased infection risk 
Xerophthalmia (blinding vs. non-blinding)
MOST DEFICIENT
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is Xerophthalmia?

A

abnormal dryness of conductive and cornea
+ inflammation
mostly associated with vitamin A deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What nutrients are absorbed in the stomach?

A 
water
ethyl EtOH
Copper
iodide
Fluoride
molybdenum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What nutrients are absorbed in the terminal duodenum and jejunum?

A

lipids
monosaccharides
amino acids
small peptides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What nutrients are absorbed in the ileum?

A 
vitamin C
folate
Vit B12
Vit D
Vit K 
Magnesium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is absorbed in the terminal ileum?

A

bile salts and acids

enterohepatic circulation to feed back to liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is absorbed in the large intestine?

A 
water
Vit K
Biotin 
Na+
Cl-
K+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the function of Calcium? In which foods, is it found?

A

Foods: dairy, sardines, green leafy veg (not spinach), fortified flour

Function: build strong bones + teeth, regulates muscle contractions, blood clotting, cardiac function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is the function of iron (HAEM)? In which foods, is it found?

A

Foods: liver, black pudding meat
- well absorbed and not affected by other dietary components

Function = O2 carrier
haemaglobin in blood
myoglobin in muscle

43
Q

What is the function of iron (NON-HAEM)? In which foods, is it found?

A

Foods: beans, nuts, dried fruit, wholegrains etc

Function: Function = O2 carrier
haemaglobin in blood
myoglobin in muscle

44
Q

Which dietary components affect the absorption of NON-HAEM iron?

A

REDUCED by tannins and phyates

INCREASED by vitamin C

45
Q

What is the function and dietary source of K+?

A

foods: bananas, broccoli, parsnips, seeds, fish, beef
function: major intracellular cation, role in acid-base balance, muscle contraction and nerve conduction

46
Q

What is the function and dietary source of Mg2+?

A

Foods: dairy, meat, fish, wholegrain bread, brown rice and green leafy veg

Functions: cofactor in enzymatic reactions (e.g. respiration), skeletal development, protein synthesis, muscle contraction,
Metabolically associated with Calcium

47
Q

What is the function and dietary source of Na+?

A

foods: salted foods
function: major extracellular cation, fluid balance, BP maintenance, transmembrane gradients

48
Q

What is the function and dietary source of phosphorus?

A

foods: meat, dairy, cereal, meat and fish
function: strong bones/teeth, release energy from food and O2 release (via ATP and NADP)

49
Q

What is the function and dietary source of Selenium?

A

foods: bread, meat, poultry, offal, nuts and eggs
function: antioxidant, immune function and thyroid hormone metabolism

50
Q

What affects selenium content?

A

the soil on which the crops are grown or animals are grazed

UK soil has low Se content

51
Q

What is the function and dietary source of Zn2+?

A

foods: meat, shellfish, dairy, bread, pulses, eggs
function: cofactor for >100 metalloenzymes, wound healing

52
Q

What is the function and dietary source of vitamin A?

A

foods: dairy, eggs, oily fish, liver products
function: night vision, development of tissues, reproduction, embryonic development and growth

53
Q

What is the function and dietary source of beta-carotene?

A

foods: yellow, red and green veg, yellow fruit e.g. mango, papaya
function: night vision, development of tissues, reproduction, embryonic development and growth

54
Q

What is the difference between vitamin A and beta-carotene?

A

Vitamin A = retinol

beta carotene is a precursor to vitamin A

Body converts beta-carotene into vitamin A

55
Q

What is the function and dietary source of vitamin B1?

A

Vitamin B1 = thiamine
foods: peas, fresh/dried fruit, fortified bread, cereals, eggs

function: release of energy from food, nervous system health

56
Q

What is the function and dietary source of vitamin B2?

A

vitamin B2 = riboflavin

foods: milk, eggs, fortified cereals, rice
functions: normal growth, integrity of mucous membranes, skin, eyes and nervous system

57
Q

What can affect riboflavin content?

A

Riboflavin = vitamin B2

UV light can destroy riboflavin so these foods should be stored out of direct sunlight

58
Q

What is the function and dietary source of vitamin B3?

A

vitamin B3 = niacin

foods: meat, fish, eggs, milk, wheat flour
function: metabolic pathways = REDOX in respiration, lipid metabolism

59
Q

What is the function and dietary source of pantothenic acid?

A

precursor to coenzyme A

foods: yeast, offal, meat, eggs, green leafy veg, fortified cereals
function: coenzyme A has central role in energy metabolism

60
Q

What is the function and dietary source of vitamin B6?

A

Vitamin B6 = pyridoxine

foods: pork, poultry, fish, eggs, milk, bread, oatmeal, wheatgerm, soya, peanuts, cereals
functions: storing energy from protein and carbs, haemoglobin synthesis

61
Q

What is the function and dietary source of vitamin B7?

A

vitamin B7 = biotin

foods: wide range but only in small levels
functions: coenzyme in many reactions e.g. lipolysis, lipogenesis and gluconeogenesis

62
Q

Why is it unclear whether exogenous biotin from diet is needed?

A

Commensal gut bacterial synthesise biotin

this may be sufficient for the requirements we have for biotin

63
Q

What is the function and dietary source of folate?

A

foods: liver (but avoid in pregnancy), yeast extract, pulses, green veg, dairy, fortified cereals
functions: folate coenzymes needed for methylation (cell division), erythropoiesis, prevention of neural tube defects in utero (e.g. spina bifida)

64
Q

What is the function and dietary source of vitamin B12?

A

vitamin B12 = cobalamin

foods: meat, salmon, cod, dairy, fortified cereals
functions: amino acid metabolism, conversion of homocysteine to methionine (in which vitamin B12 is a cofactor)

65
Q

What is the function and dietary source of vitamin C?

A

vitamin C = ascorbic acid

foods: fruits (esp. citrus), kiwi, green and red peppers
functions: antioxidant (esp in aqueous tissues), reduced Fe3+ to Fe2+ (latter is used in absorption of non-haem iron), collagen synthesis, vascular and cartilage maintenance,

66
Q

What is the function and dietary source of vitamin D?

A

vitamin D3 = cholecalciferol
vitamin D4 = ergocalciferol

foods: oily fish, red meat, egg yolks, cereals
function: Ca2+ homeostasis and absorption, regulates Ca2+ and phosphate absorption in small intestine, plasma Ca2+ levels via bone reabsorption

67
Q

What is the function and dietary source of vitamin E?

A

vitamin E = alpha tocopherol (highest bioavailability) and gamma-tocopherol (found mainly in plants)

foods: plant oils, nuts and seeds, cereals
functions: antioxidant (esp in preventing ROS damage in cell membranes and other lipid structures)

68
Q

What is the function and dietary source of vitamin K?

A

vitamin K1 = found in plant foods

vitamin K2 = synthesised by colonic bacteria

foods: green leafy veg, veg oils, cereal grains, smaller amounts in meat and eggs
functions: prothrombin formation, blood coagulation

69
Q

What is malnutrition?

A

nutritional imbalance

UNDER-nutrition vs OVER-nutrition

70
Q

What is over-nutrition?

A

excess nutrient and energy intake over time
malnutrition when over-nutrition leads to morbid obesity
number of complications linked to obesity

71
Q

What are the ranges for BMI?

A 
healthy 18.5-24.9
overweight 25-29.9
obesity I 30-34.9
obesity II 35-39.9
obesity III 40+
72
Q

What measures are used to classify obesity?

A

BMI
waist-to-hip ratio
waist circumference
waist-to-height ratio

73
Q

What are the complications of obesity?

A 
stroke
heart disease
liver disease
cancer
reproductive complications
depression and anxiety
sleep apnoea
T2DM
asthma 
osteoarthritis
74
Q

What is the prevalence of obesity in children?

A

1: 10 children in reception are obese
1: 5 children in year 6 is obese

75
Q

What is under-nutrition?

A

state in which there is a deficiency of nutrients such as energy, protein, vitamins and minerals

adverse effects on body composition, function or clinical outcome

76
Q

What are the main causes of under-nutrition?

A

starvation-related
- inadequate intake

disease related

  • malabsorption of micro/macronutrients
  • increased demand
77
Q

What are the demographics of malnutrition in the UK?

A

> 3 million people
~ 1.3 million are >65yo
25-34% of patients admitted to hospital are at risk of malnutrition

78
Q

What are the consequences of malnutrition?

A
  • weakened immune system
  • impaired wound healing
  • loss of muscle mass
  • kidney injury
  • infertility
  • apathy, depression
  • hypothermia
  • micronutrient deficiency (e.g. rickets)
  • increased hospital stay and mortality
79
Q

What screening tools are available for malnutrition?

A
  • malnutrition universal screening tool (MUST)

- subjective global assessment (SGA)

80
Q

What does the MUST score take into account?

A

MUST = malnutrition universal screening tool

  • BMI score
  • weight loss score
  • acute disease score
  • overall risk of malnutrition

total score of >2 is HIGH RISK

81
Q

How are the different MUST scores manages clinically?

A 
Low risk (MUST = 0) 
routine clinical care
Medium risk (MUST = 1) 
observe
High risk (MUST >=2) 
treat
82
Q

What does the subjective global assessment consider?

A

Medical history:

  • weight change
  • dietary intake
  • GI symptoms
  • functional impairment

Physical examination:

  • muscle wasting
  • subcutaneous fat loss
  • oedema

3 categories of SGA score:

1) well nourished
2) mild/moderate under-nutrition
3) severe under-nutrition

83
Q

What clinical signs are indicative of malnutrition?

A 
sunken eyes
skin pinch (also dehydration)
loose clothing, loose jewellery indicating weight loss
pressure sores
diarrhoea, vomiting, pain
84
Q

What tests can be used to make a nutritional assessment for malnutrition?

A

anthropometry
biochemical and haematological markers
clinical state and physical condition
diet

85
Q

What is anthropometry?

A

= external measurement of body composition

  • weight
  • BMI
  • weight loss
86
Q

What are the limitations of anthropometry?

A

difficult to obtain wright in bed bound patients

affected by oedema and ascites (fluid is not taken into consideration)

87
Q

What are the dry weight estimates for ascites?

A 
tense = 14kg
moderate = 6kg
minimal = 2.2kg
88
Q

What are the dry weight estimates for oedema?

A

severe (up to sacrum) = 10kg
moderate (up to ankle) = 5kg
mild (up to ankle) = 1kg

89
Q

How is hand grip strength used?

A

index of muscle function
measured over time
can respond more rapidly to nutritional support than other parameters
mean value is compared to reference data
<85% is cause for concern and is linked to significant morbidity

90
Q

What are the limitations of using hand grip strength?

A
  • affected by motivational status
  • improves with repeated use (accuracy of measure reduces)
  • arthritis and confusion will affect it
91
Q

What biochemical markers can be used to detect malnutrition?

A

Albumin (35-55 g/L)
levels fall when protein absorption is reduced)

Urea (6-20 mg/dL)
formed from proteolysis
low levels indicate poor protein intake

92
Q

Why are albumin levels a poor measure of nutritional status?

A
  • long half life ~ 21 days
  • levels increase during dehydration
  • levels fall during stress/infection (important to consider albumin levels with CRP)
  • poorly correlated with nutritional status
93
Q

What is the metabolic response to starvation?

A

adaptive response
prolonged starvation = BMR reduces by 30%
reduction in mass of metabolically active tissues (e.g. liver and GI tract)
protein loss minimised
glucose supply maintained

94
Q

In which order are macronutrients used following starvation?

A 
(FIRST)
carbohydrates (hepatic glycogen stores run out after days)
fats + ketones
protein 
(LAST)
95
Q

What is the metabolic response to injury, trauma or sepsis?

A

different to starvation

need to mobile energy for immune defence and repair

96
Q

What are the 3 stages of metabolic response to injury/trauma/sepsis?

A
  • Ebb phase
  • Flow phase
  • Anabolic phase (recovery phase)
97
Q

What is the Ebb phase following injury/trauma/sepsis?

A

shock
occurs within hours

  • energy reserves are mobilised, but body is shocked and struggles to use it
  • BMR falls
  • body temp falls (hypothermia)
98
Q

What is the flow phase following injury/trauma/sepsis?

A

Catabolism
occurs within days

  • breakdown of energy stores
  • BMR rises
  • body temp increase (fever)
  • acute insulin resistance
  • visceral and skeletal muscle breakdown
99
Q

What is the recovery phase following injury/trauma/sepsis?

A

anabolism
occurs within weeks

  • building up energy stores
  • nutritional therapy: increase protein synthesis and restore lean body mass
100
Q

Which injuries/trauma cause the biggest spikes in energy expenditure?

A 
highest EE
- major burns
- sepsis/peritonitis
- skeletal trauma
- elective surgery
- starvation
least EE
101
Q

What are the main metabolic processes that occur in response to starvation?

A
  • reduced BMR
  • slow weight loss (almost all from fat)
  • nitrogen loss reduced
  • early small increase in catecholamines, cortisol and GH
  • slow fall in glucagon and cortisol
  • insulin reduced
  • initial loss of water and sodium
102
Q

What are the main metabolic processes that occur in response to injury?

A
  • increased BMR
  • rapid loss of weight (80% from fat stores, 20% from body protein)
  • nitrogen losses increased
  • increased catecholamine, glucagon, cortisol and GH
  • insulin increased but with resistance (hyperinsulinaemia with IR)
  • retention of water and sodium
103
Q

What is rickets caused by?

A

Vitamin D deficiency

either due to poor diet or inadequate sunlight

Life Maintenance (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions