Practical 8 - Diabetes Lecture Flashcards
type 1 diabetes is managed through
medication mostly, but also food choice and physical activity
type 1 diabetes makes up what % of diabetes cases
10%
type 1 diabetes is an
autoimmune condition where the body attacks the cells that make insulin, which means not enough is created
type 1 diabetes is mostly diagnosed when
in children
type 2 diabetes makes up what proportion of diabetes cases
90%
what happens in type 2 diabetes
cells either don’t produce enough insulin or dont recognise that insulin is present
when is type 2 diabetes usually diagnosed
mostly diagnosed in adults, but increasing numbers of children and teenagers are being diagnosed
after we eat glucose appears in
the bloodstream
when glucose appears in the bloodstream what is released in response
insulin
when insulin receptors detect insulin what happens
insulin causes translocation of glucose transporters to the surface of the cells
what happens when glucose transporters are translocated to the surface of cells
glucose is taken into cells and blood glucose declines
what are the issues that occur in the glucose / insulin relationship in type 1 diabetes
no, or very little insulin is produced
glucose stays in the blood stream
not enough glucose gets into the cells and organs that need it for energy
what happens in a state of insulin resistance
insulin receptors stop responding appropriately to insulin
more insulin is needed to trigger translocation of glucose transporters
insulin is continued to be produced in insulin resistance because why
blood glucose remains high after a meal because glucose transporters are unable to transport it into the cells so the body continues to produce insulin to try and help
what occurs in response to defective insulin response, and after a while what starts to rise (also eventually or simultaneously what occurs)
hepatic gluconeogenesis
fasting glucose levels begin to rise
beta cells atrophy and insulin production slows
what happens when you have too much glucose in your blood
glucose travels to the kidney
causing osmotic diuresis and polyuria
polyuria leads to
dehydration and polydipsia, and polyphagia
what is HbA1c
glycated haemoglobin
higher concentrations of blood glucose overtime results in an
increase in the glycation of hemoglobin molecules (addition of glucose molecule to amino acid side chain)
HbA1c is a measure of
glycemic (blood sugar) control over previous 2-3 months
what are the HbA1c cut offs for diagnosing type 2 diabetes in NZ
> 50mmol/mol = diabetes
41-49mmol/mol = pre diabetes
<40mmol/mol = diabetes unlikely
what are the HbA1c cut offs for diagnosing type 2 diabetes internationally
> 48mmol/mol = diabetes
42-47mmol/mol = pre diabetes
<41mmol/mol = diabetes unlikely
what proportion of NZ had type 2 diabetes
somewhere between 5-7%
what proportion of NZ population have prediabetes
~20% of the population
equivalent to 2/3 of auckland
what are the long term health consequences that can be a result of diabetes
- stroke
- blindness
- heart attack
- kidney failure
- amputation
what are the risk factors for diabetes
- High BMI
- family history
- PCOS
- CVD
- long term use of oral corticosteroids
- severe mental illness
- gestational diabetes
risk of diabetes increases with what
increasing BMI
what lifestyle changes will help reduce the risk of type 2 diabetes
- reduce energy intake
- increase physical activity
- increase fibre intake
- reduce total and saturated fat intake
how does weight gain contribute to diabetes risk (positive energy balance)
being in a state of prolonged positive energy balance is associated with increased fat accumulation around muscle and organs, and increased inflammation, both of which are known to decrease peripheral insulin sensitivity
how does weight gain contribute to diabetes risk (increased triglyceride storage)
increased triglyceride storage in the liver (due to prolonged excess energy intake) reduces hepatic insulin sensitivity
how does weight gain contribute to diabetes risk (exposure of beta cells)
exposure of beta cells to fatty acids increases the rate of cell death and decreases insulin production
lifestyle interventions that incorporate a moderate physical activity component reduce incidence diabetes by
28-63% participants with impaired glucose tolerance
greater reductions are seen when the intervention also induces weight loss (but exercise alone is still effective)
in obese prevention the goal of 150 min a week is probably …..
not enough …. need to be closer to 60 mins per day
most common suggestion of physical activity to reduce the risk of diabetes
being physically active helps to prevent obesity
physical activity can influence diabetes risk both in the presence and absence of obesity
what is the effect of exercise
exercise increases skeletal muscle insulin sensitivity
muscle contraction can cause translocation of GLUT 4 without insulin
how does physical activity reduce the risk of diabetes
- improved endothelial function and capillarization
- increased mitochondiral biogenesis and fibre ratios
- improved muscular respiratory capacity and fatty acid oxidation
- increased expression and activity of GLUT 4 and glycogen synthase
what is the types of carbohydrates and their associated outcomes
higher consumption of sugars associated with poorer outcomes
higher consumption of starch associated with better outcomes
what is the recommended intake of sugar
<10% total energy
what is the outcomes associated with sugar
increased body weight
increased rate of dental caries
fibre lowers the risk of
mortality
CVD
CHD
cholorectal cancer
fibre improves
body weight, blood pressure and cholesterol
WHO recommends what for fibre intake
at least 25 grams per day of naturally occurring dietary fibre as consumed in foods
