What is good and bad cholesterol? Should you remove fat from your diet? And what about shellfish? Experts explain it all

High cholesterol can cause heart problems and strokes – but levels can creep up without showing any symptoms. This is why, if you’re over 40, you should be getting your cholesterol checked every five years. It’s a simple enough concept, but, like alcohol and other things that could be slowly, invisibly damaging our bodies, cholesterol can feel a little abstract, hovering in the background less urgently than everything in the foreground of a busy life.

It doesn’t help when myths are flying about online, such as eggs being unhealthy because they contain cholesterol. Or when some fringe scientists and proponents of low-carb and high-fat diets dramatically downplay cholesterol’s significance in heart disease – arguing that sugar is a bigger risk to our health, despite all the evidence to the contrary. Nor does it help us laypeople that there are so many different ways to present – and therefore interpret – cholesterol levels.