nutrition

Question 1

detecting inadequate nutrition

Answer 1

comparing dietary intakes with recommended intakes
adv- data available for large, representative samples
dis- individual requirements vary, poor absorption could contribute to nutrient deficiency despite adequate intake

Question 2

biomarkers of nutritional status or symptoms of deficiency

Answer 2

advantage
- will reflect malabsorption
disadvantage
- biomarkers are not available for many nutrients

Question 3

examining effects of supplementation

Answer 3

adv- any benefits will confirm appropriate treatment strategy

dis- requires symptom/biomarker

Question 4

nutritional guidelines for older people

Answer 4

macronutrient guidelines as for younger adults
protein= 0.75g/kg/day
fat= saturated= 10% , polyunsaturated=6%, momnosaturated = 12%
total fat- <33%
fibre-18g/day

Question 5

vitamin D

Answer 5

produced in skin from sun exposure so the status will differ naturally throughout the year
proportion of individuals with vitD below 25nmol/l is lowest in jul-sep and highest in jan-mar

Question 6

limitations of surveys

Answer 6

surveys are completed in healthy, independent older people
those living in residential care with acute or chronic medical conditions or cognitive impairement are more vulnerable
may not be representative of all individuals as diet will differ depending on the needs of different individuals

Question 6

vitamin D deficiency

Answer 6

common in older people
- facilitates calcium absorption
- deficiency casues bone softness and pain (rickets in children) and osteomalacia in adults
- can get from dietary intake
- can get endogenous prod in skin following sunshine exposure but lower in older people, those wihth darker skin and people who avoid sun
- vti D best in summer

Question 6

vit D supplementation

Answer 6

meta analysis found
- no effect on muscle strength
- no effect om falls or fractures
- no effect on cognititon
- reduced cancer mortality by 15%
- no effect on mortality from other causes
- reduced risk of acute resp tract infection

studies are not well regulated

Question 6

vitamin D and health outcomes

Answer 6

insuffiency is associated with
- osteomalacia
- osteoporosis
- falls
- frailty
- cancers
- cardiovascular disease
- poor cognitive function

Question 7

anaemia

Answer 7

may contribute to declining physiological and cognitive ability
may result from reduction in erythropoisis by inflammation associated with chronic disease, malabsorption of b12, iron deficiency

Question 8

iron deficiency

Answer 8

poor intake is a minor cause
malabsorption- atrophy of villi in small intestine
blood loss- gastrointestinal pathologies eg gastric cancers + stomach ulcers, infection with parasites, chronic use of non steroidal anti inflammatory drugs

Question 9

vit b12 deficiency

Answer 9

mostly not driven by low intake
loss of gastric parietal cells accounts for 15-20% of cases of cobalamin deficiency- lack of intrinsic factor
most other cases due to atrophy of cells within the gastric mucosa, ileum or bacterial overgrowth in SI

Question 10

protein energy malnutrition

Answer 10

protein deficiency
- suppressed immunity
- slow wound healing
- loss of muscle mass

Question 11

sarcopenia

Answer 11

low protein intake associated with frailty and sarcopenia
some recommend 1-1.2g/day protein in healthy adults
from studies- protein supplementation of 12-32g per day did not benefit physical function according to meta analysis although there were benefits in some stidies
protein supplementation enhances training related gains

Question 12

nutrition and frailty

Answer 12

frailty was associated with low energy intake (<21kcal/kg) OR 1.24
people with low protein, vit d,c and e and folate intake have sig increased risk of beinf frail

Question 13

social contributors to malnutrition

Answer 13

14% of UK residents >65yo were malnourished
1in 6 at risk of poverty in EU
social isolation- 1in 7 live alone- major contributor to weight loss
malnutrition increases risk of pressure ulcers- reducing immunity and healing
poor health associated with risk of malnutrition

Question 14

malnutrition prevention strategies

Answer 14

institutions
-food quality- variety, easy to eat, appropriate portion size
- environment- social context, assistance or modified utensils if needed

community
- community meals/lunch clubs or meals on wheels can prolong independent living

Question 15

calorific restriction

Answer 15

can it extend lifespan?
some metabolic and endocrinological responses
- redcued body fat content
- decreased inflammation
- reduced ROS (increased repair)
- changed activity of nutrient signalling pathways- decreased glucose/insulin signalling, decreased IGF-1 activity
- improved proteostasos- upregulation of chaperone proteins

altered apoptosis
- increased apoptosis of rapidly dividing cells eg skin
- reduced apoptosis of neuron and liver cells

hormesis theory
- stress promotes survival response which attenuates ageing

Question 16

antioxidants + ageing

Answer 16

delaying ageing
ROS formed at mitocondiral complexes I and II of ETC
may react with and damage mtDNA proteins (cross linking, glycation) and membranes (lipid perioxidtion)

dietary antioxidants - vit ACE and selenium

antioxidant supplementation doesnt reduce mortality