Cholesterol – what the numbers mean, and what changes them

Cholesterol is not a poison — your body needs it to build cells and hormones. The problem is the amount and the type circulating in the blood, because excess ends up in artery walls, narrowing them over decades.

• Total cholesterol — everything added together. Useful as a rough screen, not much use on its own.
• LDL — the one that deposits in artery walls, and the number most treatment aims at. Lower is better.
• HDL — carries cholesterol away from the arteries. Higher is better.
• Triglycerides — a different type of fat, driven strongly by alcohol, sugar and uncontrolled diabetes.

• Saturated fat — hard fats, fatty meat, full-cream dairy, coconut and palm oil, and most deep-fried and baked commercial food. This matters more for LDL than dietary cholesterol does.
• Being overweight, particularly around the middle.
• Physical inactivity, which lowers HDL.
• Smoking, which lowers HDL and damages artery walls directly.
• Uncontrolled diabetes and an underactive thyroid.
• Heavy drinking and a lot of sugar, which mainly drive triglycerides.
• Genetics. Familial hypercholesterolaemia runs in families, produces very high levels from a young age, and is under-diagnosed in South Africa.

1. 1Swap hard fats for vegetable oils — sunflower, canola or olive rather than lard, butter or hard margarine.
2. 2Eat more soluble fibre: oats, beans, lentils, split peas, apples and citrus. This has a real, measurable effect on LDL.
3. 3Eat fish a couple of times a week; tinned pilchards and sardines count.
4. 4Cut down on deep-fried food, pastry, biscuits and processed meat.
5. 5Get active — activity raises HDL, which almost nothing else does.
6. 6Stop smoking, and cut back on alcohol if triglycerides are the problem.
7. 7Lose some weight if you are carrying extra; even five percent helps.

Diet and activity typically move LDL by a useful but limited amount. For someone at high risk, that is a foundation rather than a substitute for treatment.

Statins are among the best-studied medicines in existence, and in people at genuine risk they clearly reduce heart attacks and strokes. Muscle aches are the side effect people hear about most; they do occur, but far less often than internet discussion suggests, and switching to a different statin or dose usually solves it.