What is cholesterol?
Cholesterol is a fatty substance that helps form cell membranes, various hormones, bile and vitamin D. We get some cholesterol from our diet, but most is made in our liver. Cholesterol is vital for good health however, if there is too much, more than the cells need, it can start to build up in the walls of our arteries, causing them to narrow.
Good v Bad Cholesterol
Cholesterol is carried in your blood by proteins. When the two substances combine, they’re called lipoproteins. There are two types of lipoproteins LDL (low–density lipoprotein) and HDL (high–density lipoprotein).
LDL carries cholesterol to the cells that need it, but if there’s too much cholesterol for the cells to use, it can build up in the artery walls, leading to disease of the arteries; for this reason, LDL is known as “bad cholesterol”. The amount of cholesterol in the blood – both HDL and LDL – can be measured with a blood test.
What causes high cholesterol?
Anyone can have high cholesterol, even if they are slim, eat well and are physically active. Most people won’t notice any tell-tale signs of high cholesterol. Cholesterol levels are affected by your family history, age, your lifestyle, some medicines and medical conditions. You are more likely to have unhealthy levels of cholesterol if:
Close family have high cholesterol
Your diet is high in saturated fat
You are not physically active
You drink too much, or you smoke
You carry too much weight around your middle
An underactive thyroid gland can also raise cholesterol