Cholesterol. What is it?

Updated: Jun 19, 2018

Written by Dr Alison Kamffer, SureSlim Doctor & Nutritionist.

Cholesterol is a fatty substance found in the liver, brain, nervous system and blood, and manufactured by all cells but mainly by the liver and intestine. It is essential for the normal daily activities of our cells, as well as for the manufacture of vitamin D and some hormones. The body is able to produce all that it requires even if none is eaten in the diet, but both dietary consumption and fasting reduce the amount made by the body, and consumption of large amounts of animal fat increases the amount.


Cholesterol is not soluble in blood, and so it is carried around the body in the bloodstream as lipoproteins, which are measured in a blood profile called the lipogram:

Serum cholesterol measures the total cholesterol level including that being transported. A high level is called hypercholesterolemia. The level should be less than 5.2mmol/l, but is allowed to rise with age.


Low Density Lipoproteins [LDLs ] carry large amounts of cholesterol from the liver to the cells. If there is too much it will tend to stick to the walls of the blood vessels, resulting in atherosclerosis. Thus raised levels of LDLS are less healthy.

High Density Lipoproteins [HDLs] carry cholesterol back to the liver from the other organs for breakdown and excretion. Thus HDLS are ‘HEALTHY’.

The ideal ratio of HDL:Chol is>25%