Lectures public health nutrition
Introduction
Guest lectures + workshops will not be exanimated in the exam
SR: presentation + written paper
50% written exam December 5
50% assignment (10% presentation, 90% written paper)
Workshop 1: five-minute presentation (background, answerable RQ, show literature research)
Workshop 2: ten-minute presentation (introduction/background, literature search, results so far, risk
of bias assessment, discuss one paper)
Workshop 12 December: prepare so you can do a 5-minute pitch about sustainable diets.
Lecture 1: Dietary guidelines for the prevention and management of type 2
diabetes
Diabetes, diet and development of diabetes dietary guidelines of the prevention and management of
diabetes, debate on the use of low carbohydrate diet.
Type 2 diabetes
Hyperglycaemia caused by insulin resistance (insensitivity of the tissues, they do not take up insulin)
or the main cause is reduced insulin secretion. And this is caused by unhealthy lifestyle or obesity. The
symptoms are thirst, polyuria or fatigue and after 5-10 years hyperglycemia: complications already
present. Alternatively, early detection through screening (does not happen a lot)
,Diagnostic:
IGF = prediabetes (impaired glucose tolerance)
ADA (America diabetes association)
In clinical care the symptoms are thirst, tired and polyuria and 1 time elevated fasting glucose. Or on
2 different days elevated levels.
Prevalence:
Worldwide:
- 2015 = 415 million
- 2040 = 642 million
Netherlands: over 1.200.000
Reasons: getting older with DM, people getting older, earlier detection
Complications:
Can come before diagnoses:
Retinopathy (getting blind)
Glycemic control and cardiovascular mortality:
- Total north America: RR= 1,41 (1,05-1,9) when you have a good glycemic control you have 40%
less change to die an cardiovascular mortality
- Total rest of the world + North America: 1,09 (0,90-1,32) when you have good glycemic control
you have 10% less change to die an cardiovascular mortality.
, Treatment:
1. Lowering blood glucose levels treatment:
Bad for the macrovascular diseases (CVD): strict glucose-concentrations: not effective (sometimes
even increased risk)
However, for the microvascular complications:
- Composite microvascular = reduced risk of 20% (RR = 0,82).
- And even for nephropathy = a reduced risk of 50% (RR=0,53).
- And Netrinopathy reduced risk of 20% (RR = 0,78)
One reason for this might be that HbA1c has a non-linear relation with mortality in DM2. So when you
lower up to 8% level the mortality level increases again.
2. Blood pressure lowering:
Macrovascular diseases: is effective 10/20/30% but may depend on blood pressure level at start,
mainly effective when they had a high blood pressure. Effective on mortality, CV mortality, myocardial
infarction, stroke and heart failure.
3. Cholesterol lowering therapy (statins)
Are effective in reducing CVD’s: 0,85 (0,79-0,91)
4. Lifestyle interventions
Diabetes prevention program:
- RCT 3234 participants prediabetes
o Metformin
o Lifestyle
o Placebo
- Lifestyle: 150 minutes of physical activity, reduced saturated fat intake and high fiber.
Conclusion: lifestyle is most effective for preventing DM (more than metformin, a glucose lowering
drug.
PREMID:
- Mediterranean diet
o intervention group got nuts or olive oil supplements
- They got a follow-up of 4,8 years.
- Outcomes: CVD and total mortality
Conclusion:
- risk of CVD and mortality were reduced with 30% in both groups
- DM incidence was lower in both intervention groups
- Mediterranean diet with olive oil: HR = 0,96
- Mediterranean diet with nuts: HR = 0,72
Limitations: a lot went wrong in the randomization, so they looked at the number again as an
observational study. They got similar results only there was a lower risk for microvascular
complications. And did they investigate the effect of olive and nuts instead of the Mediterranean diet?
And is the control really non-Mediterranean? This is a food group intervention instead of a diet.
Protocol deviation makes you think about the rest of the study. Randomization is important to ensure
that the groups are comparable at baseline.
EASD guideline:
Prevention CVD with people with DM through getting nuts and olive oil. BUT is it sufficient to put this
in a guideline? Because this is wrong in the randomization so maybe there also went things wrong in
the rest of the study and the study was to investigate CVD and not DM. EASD works together with CVD
guidelines, therefore you see this a lot back in their guidelines (and not reducing weight).
, EASD guideline for management of type 2 diabetes:
Richtlijnen goede voeding:
- Increase: Legumes, fiber, fish, vegetable, fruits, whole grain products, nuts
- Dairy
- Lower: refined grain products, saturated fats, red meat, salt, margarine, SSbs
- Reduced caloric intake to lower excessive body weight
- PA>150 minutes per week
NDF dietary guideline 2015
Aims:
1. Delay or prevent type 2 diabetes
2. II. Reduce acute complaints of hyper- or hypoglycemia
3. III. Delay or prevent complications
4. IV. Maintain an adequate dietary pattern
Prevention of type 2 diabetes: lifestyle intervention for body weight related health risk
“Combined lifestyle intervention” consists of:
- Calorie restricted diet with attention for improvement on long term (> 1 year)
- Increased physical activity
- If needed psychological intervention to support behaviour change
Advise according to the Dutch dietary guidelines: quality of fat and carbohydrates is more important
that the quantity.
Dutch healthy diet index and risk of DM the Hoorn study
Risk of DM when patients were adherence to the guidelines was reduction up to 25%
Treatment:
DM1: emphasis on alignment of dietary pattern and carbohydrates with insulin to reach an optimal
regulation of DM to prevent or delay complications
DM2: emphasis on maintaining or reaching a healthy body weight, as 80% of people with DM2 are
overweight by sufficient physical activity and reducing the risk of complications.
Treatment of DM with overweight:
- Recently diagnosed: aim for 5-10% body weight reduction
- At short term (<1year): carbohydrate reduced diet is beneficial in terms of body weight, lipids
and cardiovascular risk than fat reduced.
- Intensive lifestyle programs with professional guidance for dietary, physical activity and
behaviour change are preferred
BMI >30 kg/m2, comorbidities or insufficiently regulated
- Low Calorie Diet (1000 kcal/day)