High cholesterol explained: LDL, HDL and your real risk

You end up holding a results slip with four or five numbers on it and a ratio. Someone has told you your cholesterol is high. Nobody has explained which part of it is high, whether that matters for you specifically, or what you are supposed to do differently on Monday morning.

Cholesterol is one of the most misunderstood things in medicine, mostly because it gets flattened into a single good or bad verdict. It is not one number, and it is not really about eggs.

It is also a condition of years rather than weeks. Nothing about it needs deciding today, and a fair amount of it needs deciding carefully, with someone who has looked at your whole picture rather than one line on a page.

What cholesterol is actually doing in your body

Cholesterol is a waxy fat that your body needs. It goes into the wall of every cell you have, into hormones, into vitamin D, into the bile that digests your food. Your liver makes most of it. You eat only a minority of it, which is why cutting out one food rarely transforms a result.

The problem is not its existence. It is how much is circulating, in what form, and what that does to your artery walls over decades. Fatty deposits build up gradually, the artery narrows, and the risk of a heart attack or stroke rises. That process is slow, which is both the reassuring part and the reason it gets ignored.

LDL and HDL, in plain language

Cholesterol travels around your blood inside particles, because fat does not dissolve in water. The names describe the transport, not the cholesterol itself.

• LDL carries cholesterol out from the liver to the tissues. When there is more of it than your body needs, the surplus ends up in artery walls. This is the fraction clinicians most want lower.
• HDL does more of the return trip, taking cholesterol back to the liver. Higher tends to be better, though not a score you can raise to cancel out the rest.
• Triglycerides are a different fat on the same result, and they respond strongly to alcohol, sugary drinks and refined carbohydrate. They often sit alongside weight and blood sugar problems.
• Total cholesterol is the headline figure and, on its own, the least informative of the lot, because it lumps the helpful and the unhelpful together.

So when someone tells you their cholesterol is a certain number, the follow up question is always which number.

Why it is about risk, not a single result

Here is the shift that makes cholesterol make sense. A clinician is not trying to fix a number. They are estimating your chance of a heart attack or stroke over the coming years, then deciding what is worth doing about it. Cholesterol is one input into that estimate.

The others include your age, your sex, your family history (particularly a parent or sibling with early heart disease), your blood pressure, whether you smoke or have diabetes, your kidney function, your weight and your ethnicity. Two people with identical cholesterol results can be given completely different advice, and both can be right.

This is also why the figures a clinician watches are not targets for you to manage yourself. They are one part of a judgement, and their meaning changes with everything around them. Blood pressure is a major part of the same calculation, so a blood pressure management plan often runs alongside cholesterol work rather than separately. An underactive thyroid can push cholesterol up too, which is one reason thyroid problems get considered when a result looks unexpected.

Food and movement: what actually shifts things

Diet does matter, just not in the way most of us were taught. The bigger lever is the type of fat rather than the total, and swapping saturated fat for unsaturated fat is the change with the most behind it. In practice that means less butter, fatty and processed meat, pastry, biscuits and cream, and more olive or rapeseed oil, oily fish, nuts, seeds and pulses.

Soluble fibre helps, which is the quiet argument for oats, barley, beans and lentils. Alcohol and sugary drinks push triglycerides up and are often the easiest thing to change. Regular activity nudges HDL up and triglycerides down while helping your blood pressure and weight, which is a better deal than it sounds. Stopping smoking does more for your cardiovascular risk than any single dietary change.

None of this produces a dramatic result in a fortnight. Give changes months rather than weeks, and judge them on a repeat result rather than on how virtuous you feel.

When to get urgent help

High cholesterol itself causes no symptoms. What it contributes to certainly does. Treat the following as possible heart symptoms needing urgent assessment, not as something to monitor at home:

• Chest pain, heaviness or tightness, especially when you exert yourself and it eases when you stop.
• Pain spreading from your chest to your jaw, neck, shoulder, arm or back.
• Breathlessness that is new, or out of proportion to what you are doing.
• Chest discomfort with sweating, nausea or a sense of dread.
• Sudden weakness or numbness down one side, drooping on one side of the face, or slurred speech.
• Calf pain that comes on reliably when you walk a certain distance and settles with rest.

Chest pain that is severe, lasts more than a few minutes, or comes with sweating or breathlessness is a 999 call, and so are stroke symptoms. Do not drive yourself and do not wait it out to see whether it passes. If your symptoms are milder and you are unsure how quickly to act, 111 can tell you, and a face to face assessment is usually what is needed rather than an online appointment. Established heart disease has its own route, and ongoing heart medication reviews are handled as a plan.

How a medication decision actually gets made

Nobody should be handed a tablet with no explanation, and nobody should be talked out of one by an argument they read online either. A reasonable conversation covers your estimated risk, how much a medicine such as a statin would be expected to reduce it, the common side effects and what to do if you get them, what happens if you do nothing, and how long you would be taking it.

That last one matters, because this is usually long term. The decision is yours to make with a doctor, and it is a genuine decision rather than a formality. Where the doctor judges treatment clinically appropriate they can prescribe it, and they will want to review how you are getting on afterwards rather than leaving you to it. Never start, stop or change a cholesterol medicine on your own, including after a scare story. Ongoing reviews are what a monthly cholesterol management plan is designed for.

How an online cholesterol review works

Most of a cholesterol review is discussion, which is why video suits it. Bring your most recent results if you have them, a list of your current medicines, and whatever family history you know about. The doctor goes through what the numbers mean for you, what your overall risk looks like, and what the realistic options are. The way a video consultation is arranged is set out step by step and the fees in pounds are published, so you know what you are agreeing to before you book a video consultation.

If you are sitting on a result nobody has properly explained, get it explained. Arrange a cholesterol review with a UK registered doctor and walk away with your real risk picture and a plan you can follow, revisited as things change rather than filed and forgotten.