Hyperlipidaemia is the medical term for too much fat in the blood.
Lipids, or fats, are normal constituents of the watery part of the blood,
known as plasma. There are several different types of lipid but only two
need concern us here, cholesterol and triglyceride.
Cholesterol is an important constituent of all our cells. Part of the
cholesterol in plasma comes from the liver, where it is made, the remainder
being absorbed from the diet. Ideally the level of cholesterol in plasma (or
serum) should not exceed 6.0-7.5 millimoles per litre (mmol/l), depending
upon the age and sex of the individual concerned.
Triglyceride is an important source of energy and, like cholesterol, is
both made in the liver and absorbed from the diet. Any excess which is not
used up as fuel during exercise is stored as subcutaneous fat or adipose
tissue. Triglyceride levels in plasma rise after a fatty meal but ideally
should not exceed 2.0-2.5 mmol/l after an overnight fast.
From this it should be obvious that hyperlipidaemia exists when levels
of cholesterol and/or triglyceride in the blood are abnormally high. An
increase in cholesterol is termed hypercholesterolaemia; an increase in
triglyceride is termed hypertriglyceridaemia.