Nutrition and CVD

Question 1

What is the incidence of CVD in the UK?

Answer 1

Accounts for almost one in two deaths in UK and is leading cause of premature death in UK

Question 2

What is the most common form of CVD?

Answer 2

CHD

Question 3

What non-modifiable risk factors are there for CHD?

Answer 3

Gender- females protected
Age >65 years
Family history of CHD
Ethnicity
Co-morbidities- diabetes and renal disease
Socio-economic status

Question 4

What modifiable risk factors are there for CHD?

Answer 4

Body weight
Body shape
Blood pressure
Blood lipids
Lifestyle

Question 5

What did the interheart study show?

Answer 5

9 modifiable risk factors that account for over 90% of initial acute myocardial infarction:
Smoking
Hypertension
Lipids
Abdominal obesity
Diabetes
Fruit and veg
Alcohol
Physical activity
Psychosocial factors and others

Question 6

What are the several mechanisms by which diet potentially influences risk of CHD?

Answer 6

Lipid levels- LDL, HDL, TG, lipoprotein(A)
Blood pressure- salt intake (high BP->damage to endothelium->inflammatory response, inflammatory cells may take up LDL forming foam cells and atherosclerosis)
Cardiac rhythm (fish oils)
Endothelial function- Types of fats
Systemic inflammation- CRP and IL-6 are predictors of CVD in women, trans fat increases these markers and so does obesity
Insulin sensitivity- body weight and dietary fat

Question 7

What is the main problem with evidence based guidelines?

Answer 7

Little high quality evidence

Question 8

What are the UK recommendations for diet in terms of MI?

Answer 8

Advise people to eat a Mediterranean style diet
Don’t routinely eat oily fish to avoid another MI
Don’t offer people to use omega 3 fatty acid to avoid another MI
Advise people not to take beta-carotene supplements, antioxidant supplements or folic acid to reduce CVD risk
Education- offer individual consultation on diet
Consistent advice
Keep weekly alcohol consumption within safe limits

Question 9

Why is a mediterranean diet protective post MI?

Answer 9

More fish, fruits and veg, less sat fat and partial replacement by rapeseed or olive oil- more emphasis on fresh food

Question 10

What does the mediterranean diet involve?

Answer 10

Pulses, beans, legumes
Fruit and veg
Less alcohol
Fish
Low saturated fats
Nuts, seeds
Olive oil and pasta/bread

Question 11

What is the overall effect of changing fat intake?

Answer 11

Decreasing CVD

Question 12

What is the difference between MUFA/PUFA and trans fatty acids?

Answer 12

Cis double bond is changed to a trans double bond

Question 13

What are the effects of trans FA?

Answer 13

Increase LDL cholesterol
Decrease HDL cholesterol
Increase CHD risk
Suppress epithelium growth factors
2% increase in total energy from TFA -> increase CHD by 23%
Greater effect than saturated fat in reducing the TC:HDL ratio

Question 14

What are the three major groups of fats?

Answer 14

Saturated- butter, lard, cheese, fatty meat, coconut
Polyunsaturated- Sunflower, soya, safflower, corn, sesame and fish oils
Monounsaturated- Olive, peanut/walnut, rapeseed/canola, avocado and almonds

Question 15

What is the effect of lipids?

Answer 15

All fats increase HDL except trans fatty acids
MUFA increase HDL more than PUFA but PUFA lower LDL more than a MUFA
Trans FA have detrimental effect across the spectrum

Question 16

What effect do fruit and veg have?

Answer 16

Decrease risk of CHD
An increase of 1 portion of fruit and veg/day decreases risk of CHD by 4% and of stroke by 6%
Also helps lower blood pressure

Question 17

What is the recommended adult fibre intake?

Answer 17

18g/day

Current UK adult intake is 12g/day

Question 18

What does plenty of fibre in diet help?

Answer 18

Insoluble fibre helps to prevent constipation and improve bowel function (e.g. wholegrain cereals and wholemeal bread)
Soluble fibre can help lower blood lipid levels/cholesterol (e.g. fruits, veg, oats, rice, bran and pulses)

Question 19

What slowly absorbed starchy foods are there?

Answer 19

Oats, potato, fruit, barley, basmati rice, beans and lentils, pasta and noodles, wholegrain bread

Question 20

What fatty acids do oily fish have?

Answer 20

N-3 fatty acids- DHA and EPA fatty acids (long chain fatty acids with multiple double bonds)

Question 21

What are the protective effects of N-3 fatty acids?

Answer 21

TG reduction
Reduced blood clotting
Improved endothelial function
Platelet inhibition
Stabilisation of plaque structure
Anti-arrhythmic effects

Question 22

How is hypertension linked to CHD?

Answer 22

It is an independent risk factor for CHD- A decrease of 3-5mmHg of systolic blood pressure reduces CHD risk by 10% and stroke by 15%

Question 23

What does the DASH diet contain?

Answer 23

Rich in veg, low in fat and low in salt

Question 24

What is the recommended daily salt intake?

Answer 24

No more than 6g/day

Current average is 9g/day

Question 25

What are the main sources of salt in our diet?

Answer 25

Cereals, breads, biscuits, cakes and pastries

Question 26

How does dietary salt have an effect on BP?

Answer 26

High dietary salt raises CSF Na+ -> Increased SNS activity -> Vasoconstriction -> increase in central ouabain (Na-K ATPase inhibitor) -> increase ACTH -> increase RAAS -> high dietary salt -> endogenous oubain, Na+ pump ligand -> vasoconstriction

Question 27

What are the recommended weekly alcohol guidelines?

Answer 27

<21 for men and <14 for women

Question 28

What are the recommended daily alcohol guidelines?

Answer 28

<3-4 units for men | 2-3 units for women

Question 29

What is binge drinking?

Answer 29

>3 drinks in 1-2 hours or 2x daily limit (8u for men and 6u for women)

Question 30

How do sterols work?

Answer 30

Stanol/sterol compete for sites where cholesterol sits in the micelle formation as it travels through the GI tract. If cholesterol can't enter the micelle, it is lost from the GI tract as it can't be reabsorbed Plant sterols/stanol esters are clinically proven to reduce LDL cholesterol by 10-15%

Question 31

What does soy protein do?

Answer 31

It has modest effects on reducing cholesterol 25g of soya protein/day lowers LDL, cholesterol and triglycerides It protects epithelial surface

Question 32

In terms of cholesterol, what do the guidelines recommend?

Answer 32

Keep dietary cholesterol <300mg/day

Question 33

What are high dietary sources of cholesterol?

Answer 33

Eggs, offal and shellfish

Question 34

How does BMI affect risk of diabetes?

Answer 34

BMI >30kg/m2 have 40 fold increase in risk of diabetes | 2-3 fold risk of CHD

Question 35

How is central obesity measured?

Answer 35

By waist circumference (better predictor of CVD risk than BMI)

Question 36

What are the benefits of 10% weight loss?

Answer 36

Realistic, a lot of benefits: Mortality- >20% fall in total mortality, >30% fall in DM related deaths, >40% fall in obesity related deaths Blood pressure- Fall of 10mmHg systolic and 20mmHg diastolic Diabetes- fall of 50% in fasting glucose and 50% less likely to develop Lipids- Fall of 10% of total cholesterol, fall of 15% in LDL, fall of 30% in triglycerides and increase of 8% in HDL

Question 37

What is the main dietary recommendation for people with CVD?

Answer 37

``` Advise people to eat a Mediterranean style diet: Bread/pasta Fruit and veg Beans, pulses, legumes Olive oil, nuts, seeds Fish, less meat ```

Question 38

What would you suggest to reduce LDL?

Answer 38

Decrease saturated fatty acids and trans fats Choose PUFA and MUFA Soluble fibre Weight loss in the overweight and obese

Question 39

What would you suggest to increase HDL?

Answer 39

Increase physical activity Weight loss Improved glycaemic control in diabetes Moderate alcohol consumption

Question 40

What would you suggest to reduce triglycerides?

Answer 40

``` Increase physical activity Weight loss Improved glycaemic control Reduced alcohol consumption Reduced sugar consumption Increased oily fish consumption ```