nutrtion and immune health

Question 1

importance of nutrition and immune health

Answer 1

affect all aspects of immune system
macronutrients - immune cell metabolism and protein synthesis
micronutrients - immune cell replication and antioxidant defences

Question 2

impact of nutrient deficiencies

Answer 2

impair immune function
depressed cell mediated immunity
t-lymphocyte proliferation
complement formation
phagocyte function
humoral and secretory antibody production
altered cytokine production

Question 3

direct negative effects of inadequate nutrition on immune function

Answer 3

altered availability of nutrients/coenzymes/cofactors involved in immune cell energy metabolism and protein synthesis

Question 4

direct negative effects of inadequate nutrition on immune function

Answer 4

immunotegulatory effects of stress hormones

altered hormone response to stress

increase in:
adrenaline
acth
cortisol
glucagon
insulin
testosterone

Question 5

decrease in immune function

Answer 5

decrease in
cell mediated immunity
cell proliferation
complement formation
phagocyte function
antibody production/affinity

increase in URTI

Question 6

how does cho effect immune function

Answer 6

glucose acts as fuel substrate for immune cells - post exercise hypoglycaemia could endanger immune cell function

catecholmaines (adrenaline and noradrenaline) and cortisol, potent modulatory effects on immune function, increasing cho may more likely act indirectly by reducing stress hormone responses, limiting exercise induced impairments

Question 7

evidence for CHO supplementation

Answer 7

lack of evidence that cho modifies infection risk in athletes

is evidence for stress hormone response and in vitro immune responses, acute supplement during exercise

shown to enhance aspects of recovery and performance

Question 8

prescription of CHO

Answer 8

30-60g per hour during sustained intensive exercise
consume 1-1.2g/kg 0-2 hours post exercise
absolute amount adjusted on intensity and duration

attenuate rise in stress hormone, limit degree of exercise induced immune impairment

train low strategies, periodise training to reduce immune impairment and ability to perform

Question 9

what’s class as vitamin d deficiency

Answer 9

<30nmol/l

Question 10

maintenance dose for vitamin d

Answer 10

1000-2000iu/day

Question 11

reverse vitamin d deficiency

Answer 11

4000 iu/day

Question 12

what vitamin should you supplement with

Answer 12

vitamin d3

Question 13

what should you take into account when supplementing vitamin d

Answer 13

latitude, skin type, train indoors, religious clothing

Question 14

should you supplement if you have enough vitamin d

Answer 14

no avoid excess intake

Question 15

what was seen in people who were vitamin d deficient

Answer 15

67% deficient reported urti
27% who had optimal levels reported URTI but illness severity was less
He and colleagues 2013

Question 16

where do we get vitamin d from

Answer 16

sun exposure 90%

Question 17

how much vitamin d do we need

Answer 17

5-15 ug/day

Question 18

evidence for vitamin d supplementation

Answer 18

moderate to strong
deficiency associated with increased risk of URTI

Question 19

how does vitamin d effect immunity

Answer 19

anti inflammatory, influences several aspects of immunity

both innate and acquired arm through modulation of gene expressions

up-regulates gene expression and antimicrobial peptides and downregulates expression of inflammatory cytokines

immunomodulatory effect of t and b lymphocytes in acquired immunity

Question 20

how should you supplement probiotics

Answer 20

14 days prior to overseas travel or comp to ensure colonisation

multi strain probiotics, genus lactobacillus and bifdobacterium

more than 1x10 to the 9 - 1billion cfu to ensure greatest survival in gut and immune modulation

Question 21

side effects of probiotics

Answer 21

transient increase activity in the gut during consolation period

rumbles, flatulence

athletes should be informed of possible mild side effects

Question 22

what are probiotics useful for

Answer 22

reducing the risk of common respiratory and gut issues by improving immune and gut barrier function

during prolonged and intensive exercise mucosal surfaces can be disturbed, increasing risk of common gut problems

Question 23

how do probiotics work

Answer 23

increase secretion of mucins and iga
enhance gut wall integrity
inhibit the overgrowth of pathogenic bacteria
competing with pathogenic bacteria for binding sites on mucins and/or epithelial cells

Question 24

evidence for probiotic use

Answer 24

moderate to strong evidence in athletes with a daily dose

50% decrease in URI incidence and 2 days shortening of URI length

more evidence required for supporting probiotic efficacy to reduce gastrointestinal distress and infection

some benefit with little evidence of harm

Question 25

probiotics effect on systemic immunity

Answer 25

enhance innate and acquired arm of immune system

in vitro studies enhance phagocytic capacity of PBMC’s as well as NK cell cytotoxic activity and significantly increases specific IGA and immunoglobulins