Public Health Nutrition HC 28-10-2019
Dietary Guidelines
Diabetes
Characterised by:
Hyperglycaemia
IR, reduces insulin secretion
Diagnosis with symptoms (thirst, polyuria, fatigue) after 5-10 years of hyperglycaemia
Alternatively early detection through screening: measure glucose concentrations
Diagnostic criteria in clinical care are symptoms like thirst and one times elevated fasting
glucose or on two different days elevated levels. Based on:
Fasting glucose: >7.0 mmol/L
2-hour glucose: >11.1 mmol/L
HbA1c: >48 mmol/L
Prevalence: 1.200.000 people in the Netherlands. Increase is due to the aging population
and the epidemic of obesity and unhealthy lifestyle. But also improved treatment.
Complications:
CVD: 2-4 times increased risk
Retinopathy: 10-20 %
Nephropathy: after 10 years 0,8% renal failure
Neuropathy: after 10 years 3,6%
Treatment: has as primary focus glycaemic control and CV mortality.
Strict glucose concentrations: macrovascular complication not improved. Reduced
risk of about 20% in microvascular complications, 50% nephropathy, 20%
retinopathy. One reason for this might be that HbA1c has a non-linear relation with
mortality in diabetes. So when you lower up to 8% level the mortality level increases
again.
Blood pressure lowering treatment: effective on mortality, CV mortality, myocardial
infarction, stroke, heart failure. But depending (a little) on blood pressure levels at
start. Mainly effect in patients with diabetes and a high blood pressure.
Cholesterol lowering therapy (statins): effective in reducing major CV complications
Life style intervention: physical activity, reduced saturated fat, high fibre intake
o Mediterranean diet: risk for T2DM, CVD and mortality reduced
o Lot of participants are needed with pre diabetes
o Taking a pill is easier than changing peoples lifestyle not a lot of evidence
yet
Diet and development
Diabetes prevention program included 3234 participants in a RCT with metformin, lifestyle
and placebo for four years.
,Metformin is a glucose lowering medication
PREDIMET with a Mediterranean diet compared to control. One intervention group was
supplemented with olive oil and the other was supplemented with nuts. Showed that the risk
of CVD was reduced by amount 30% also diabetes incidence was lower for both intervention
groups compared to control. However, the study was retracted because there were a lot of
protocol deviations. They messed around with randomisation. they repeated the analysis
but this time as an observational study. They found similar results. There was a lower risk for
microvascular complications. Aren’t you investigating the effect of olive and nuts instead of
the Mediterranean diet? Is the control really non Mediterranean? Food group intervention
instead of diet. Protocol deviation makes you think about the rest of the study.
Randomisation is important to ensure that the groups are comparable at baseline.
The guideline for people with diabetes includes:
Increase: whole grain, fibre, legumes, fruits
Lower: refined grain products, margarine, red meat, salt, sugar sweetened
beverages.
Reduced caloric intake to lower excessive body weight
PA > 150 minutes / week
Dietary guidelines for prevention
Aims:
1. Delay or prevent T2DM
, 2. Reduce acute complaints of hyper- or hypoglycaemia
3. Delay or prevent complications
4. Maintain an adequate dietary pattern
Prevention of T2D: lifestyle is effective for body weight related health risks. The combined
lifestyle intervention consists of:
Caloric restricted diet with attention for improvement on long term
Increased PA
If needed psychological intervention to support behaviour change
Advise according to Dutch dietary guidelines is that quality of fats and CHD is more important
than quantity. Risk of diabetes was decreased with 25% when patients adhered to guidelines
Type 1 diabetes: emphasis on alignment of dietary pattern and carbohydrates with insulin to
reach an optimal regulation of diabetes to prevent or delay complications.
Type 2 diabetes: emphasis on maintaining or reaching a healthy body weight, as 80% of
people with type 2 diabetes are overweight by sufficient physical activity and reducing the
risk of complications.
Treatment of diabetes with overweight should aim for 5-10% weight reduction. At short-term
CHD reduced diet is beneficial in terms of body weight, lipids and CV risk than fat reduced.
Intensive lifestyle programs with professional guidance for dietary, physical activity and
behaviour change are preferred. When BMI > 30, low or very low caloric diet (500-1000 kcal/
day) to have a quick reduction of body weight, improved glycaemic control and reduction of
CV risk factors. With longer duration of diabetes, in consultation with patient, more attention
towards prevention of weight gain than reduction of body weight.
NHG-standard: For each patient: no smoking, sufficient physically active, weight reduction
when BMI>25, healthy diet, if necessary refer to dietician. Healthy diet: according to Dutch
guidelines; reduce saturated fat, increase unsaturated fat, increase fibre intake and little
alcohol, no supplements. It is very brief. How would a GP help people to stop smoking and to
reduce their body weight.
Treatment of type 1 and type 2 diabetes:
No specific energy % targets for macronutrients
According to different dietary patterns: Mediterranean and low CHD
Replacement of high glycaemic products by low glycaemic products
Intake of saturated fat has a negative impact on body composition
Advise to reduce saturated fat and replace by mono- or poly unsaturated fat
Trans-fat increases cardiovascular risk factors
Food products high in omega-3 fatty acids improve cholesterol levels
Do not advise for omega-3 supplements but eat fish one a week
Metformin can cause vitamin B12 deficiency (6-33% dependent on dose, duration)
o Consequences: neuropathy, depression, cognitive function (not significant)
o Advise: screening for vit B2 deficiency in metformin is not advised because
there is insufficient evidence.
o Check in certain situations: serum B12, methyl malonic acid, supplement
Vitamin D: supplement only with risk of deficiency. No effect on diabetes
development.
Alcohol consumption: do not consume more than 1 glass alcohol per day
o Extra CHD due to hypoglycaemic effect of alcohol
, o Moderate alcohol consumption lowers fasting plasma glucose and improve
insulin sensitivity after 2 years
o MA: different CV outcomes moderate alcohol consumption improved with
moderate alcohol consumptions but other parameters decreased. Lot of
debate.
The LOOK AHEAD study is a lifestyle intervention in type 2 diabetes.
Randomized controlled trial
5145 overweight of obese people with diabetes
Lifestyle intervention focused on caloric restriction and increased physical activity
1200 to 1800 kcal per day with 15% from protein
Diabetes support and education
Primary outcome: composite of death from cardiovascular causes during a maximum
follow-up of 13.5 years
Effect of lifestyle intervention on CV risk:
Body weight: reduction first steep decrease after that increase but not as much
compared to control.
Physical fitness: increase compared to control
Waist circumference: follows line of body weight
Glycated haemoglobin: steep decrease, after that going up again. Overall intervention
lower compared to control
CV endpoints: line is almost identical non-significant results
Intensive lifestyle intervention study and glycaemic control in type 2 diabetes
Randomized, assessor-blinded, controlled trial
98 participants with type 2 diabetes diagnosed < 10 years
Lifestyle versus standard care
5-6 weekly aerobic training sessions (cardiac & resistance)
Dietary intervention aiming at BMI < 25
Macronutrient distribution of 45-60%carbohydrate, 15-20% protein, and 20- 35%fat