Lecture 12 AI generated

Question 1

Describe the hierarchy of scientific evidence in nutrition research.

Answer 1

In nutrition research, the hierarchy is: RCT/prospective cohort studies > retrospective case-control > ecologic studies > case series.

Question 2

What are the different types of lipids ingested from the diet?

Answer 2

Different types of lipids ingested from the diet include triglycerides (fatty acids), fat-soluble vitamins, phospholipids, dietary cholesterol, and plant sterols.

Question 3

How is dietary fat absorbed in the body?

Answer 3

Dietary fat is taken up as large triglyceride droplets, which are broken down into monoglycerides and free fatty acids in micelles. These are absorbed in the gut wall, transformed back into triglycerides, and packed into chylomicrons for delivery to the blood.

Question 4

Define biomarkers in nutrition research.

Answer 4

Biomarkers are the most used research methods in nutrition research and refer to measurable indicators that reflect biological processes or responses to dietary intake, helping assess the risk of diseases like cardiovascular disease.

Question 5

Describe the process of lipid transportation in the body.

Answer 5

Lipoproteins serve to transport all kinds of lipids in the body. Chylomicrons, produced in the gut, are transported to the liver where they are converted to VLDL, then to IDL, LDL, and finally to HDL, which play crucial roles in lipid metabolism and cardiovascular health.

Question 6

Describe the classification of lipoproteins based on density and size.

Answer 6

Lipoproteins can be classified by their density and size.

Question 7

What is the association between elevated LDL-C concentrations and atherosclerosis/CHD risk?

Answer 7

Elevated plasma/serum LDL-C concentrations are strongly associated with atherosclerosis and CHD risk.

Question 8

Define the relationship between LDL-C reduction and CHD mortality.

Answer 8

A 10% lowering in LDL-C can cause a 7% reduction in CHD mortality.

Question 9

How is a low plasma HDL-C concentration linked to CVD risk?

Answer 9

A low plasma HDL-C concentration is linked to an increased CVD risk.

Question 10

Explain the role of HDL-C as a risk predictor in CVD.

Answer 10

HDL-C concentration is an independent risk predictor, but not an independent risk factor.

Question 11

Describe the association between plasma TG concentration and CHD risk.

Answer 11

Observational studies show that TG concentrations are associated with higher CHD risk, independent of LDL-C.

Question 12

What is the summary regarding LDL-C, HDL-C, and TG in relation to CHD risk?

Answer 12

LDL-C is an established causal risk factor for CHD. HDL-C is a biomarker of CHD risk, but not a causal factor. TG are a marker of remnant cholesterol and risk predictor, but not an established independent risk factor for CHD.

Question 13

Describe the effects of phytosterols on fat metabolism.

Answer 13

Phytosterols can help lower LDL-C by reducing cholesterol absorption and increasing excretion, thus lowering cholesterol levels. They can be found in various plant-based foods.

Question 14

How can LDL-C be lowered using dietary changes and supplements?

Answer 14

Lowering LDL-C can be achieved by reducing saturated fat, increasing unsaturated fat intake, consuming plant sterols, increasing fiber, and incorporating soy protein. Additionally, foods with added plant sterols can help lower LDL-C.

Question 15

Define the main sources of plant sterols.

Answer 15

Plant sterols can be found in foods like sunflower seeds, peanuts, soybean, orange, broccoli, wholemeal bread, olive oil, apple, and carrot.

Question 16

What is the impact of phytosterols on cholesterol absorption and excretion?

Answer 16

Phytosterols reduce cholesterol absorption in the body and increase its excretion, leading to lower LDL-C levels.

Question 17

How do phytosterols contribute to lowering LDL-C levels in the body?

Answer 17

When about 2 g/day of phytosterols are added to foods, they can lower LDL-C levels by approximately 10%, especially when combined with a healthy diet or statins.

Question 18

Describe the role of fat in a healthy diet.

Answer 18

Fat is essential in providing energy, essential fatty acids, acting as a carrier for fat-soluble vitamins, and enhancing the taste and flavor of foods.

Question 19

What did Unilever’s research conclude about the impact of plant sterols and stanols on LDL-C concentrations?

Answer 19

Unilever found that LDL-C concentrations can be lowered by plant sterols and stanols, especially when incorporated into a healthy diet or combined with statins.

Question 20

What is the recommended intake of saturated fatty acids (SAFA) according to the content?

Answer 20

<10%

Question 21

Describe the recommended intake of polyunsaturated fatty acids (PUFA) according to the content.

Answer 21

6-11%

Question 22

How does the replacement saturated fatty acids (SAFA) with monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) affect the blood lipid risk profile?

Answer 22

It is most effective for improving the blood lipid risk profile.

Question 23

Define iso-caloric replacement fat in the context of the content.

Answer 23

When fat intake changes, intake of one or more other calorie-delivering macronutrient(s) must change as well to keep energy balance.

Question 24

Do observational studies suggest a beneficial effect of replacing saturated fatty acids (SAFA) with polyunsaturated fatty acids (PUFA)?

Answer 24

Yes, observational studies indicate that the replacement of SAFA by PUFA is beneficial.

Question 25

Describe the effect of replacing 5% of saturated fatty acids (SAFA) with polyunsaturated fatty acids (PUFA) on LDL-C according to nutrition intervention studies.

Answer 25

It will lower LDL-C by 0.25 mmol/L (7%).