Doctor, doctor: Statins and cholesterol

Why might my GP be undecided about prescribing statins to counter my high cholesterol level?
Blood pressure illustration
High cholesterol comes in many forms. Photograph: Aaron Tilley for the Guardian

I have raised blood cholesterol and my GP is considering prescribing a statin. I'm otherwise healthy, 45 and female. Why is my doctor hesitating? Should he not just give me the drug?
Statins block the synthesis of cholesterol in the liver, so reducing circulating cholesterol levels. That should lower heart attack and stroke risk, and the chances of fat being deposited in artery walls, but it isn't straightforward. Cholesterol has three main components: LDL, HDL and triglycerides (TG). High LDL and TG with low HDL raise the risk; the converse reduces it. As your cholesterol score is a combination of the three, your GP will take each into account. Statins reduce LDL levels, and some raise HDL levels, too, but they don't alter TG much. If, say, your total cholesterol is linked to a higher than normal HDL, you would not need treatment. High TG would be treated by a "fibrate" rather than a statin. If your test shows a high TG and normal HDL and LDL, you may be drinking too much alcohol, so expect your GP to ask about it.

Got a question for Dr Tom? Email