Chapter 9 Diet, the Control of Blood Lipids and the Prevention of Heart Disease

Question 1

describe the relationship between the intake of various types of dietary lipids and the blood level of lipids.

Answer 1

elevated levels of total cholesterol, low density lipoprotein cholesterol and triglycerides, increased CHD risk.
A greater ratio of TC (total cholesterol) to HDL-C indicates an increased CHD risk.
Diet can increase or decrease CHD risk via changes in the blood lipid profile as well as other risk factors (e.g. oxidative stress, elevated blood pressure and inflammation) 9.1

Question 2

describe how various dietary changes affect the blood lipid level.

Answer 2

certain saturated fatty acids, trans fatty acids, conjugated linoleum acids (CLA) and cholesterol adversely affect blood lipid levels,
whereas viscous fibre, unsaturated fatty acids, MUFAs and PUFAs, plant sterols and to a certain extent polyphenols have a favourable effect.
alcohol in moderation positively influences the lipid profile, whereas adverse effects have associated with excessive consumption. 9.2

Question 3

What is the effect of an increase in dietary cholesterol on the blood cholesterol level? 9.2.6

Answer 3

Studies have been inconsistent.
Most studies have indicated that increased dietary cholesterol raises the total cholesterol in blood…but some studies have shown no association.

Question 4

Discuss the relative importance of trans fatty acids in the control of blood cholesterol. 9.2.2

Answer 4

TFAs behave like SFA’s in that they seem to increase LDL-C but also adversely affect the good HDL-C

Question 5

Discuss the relationship between eating nuts and risk of CHD.

Answer 5

nuts seem to beneficial in lowering CHD risk because they are high in MUFAs and PUFAs

Question 6

Discuss the Portfolio Diet in terms of its effectiveness for preventing CHD and whether it is
likely to be widely acceptable to cardiac patients.

Answer 6

Goal is to achieve a maximum LDL-C lowering effect.
it is a vegetarian diet that includes plant sterols and viscous fibres, primarily from oat, barley and psyllium, in addition to soy protein and almonds.
It is successful however it is not a type of diet that many are willing to accept on a long term basis.