High Cholesterol Runs in My Family. It Has a Name.

If high cholesterol runs in your family — a parent on statins in their forties, a grandparent who had a heart attack far too young, your own reading stubbornly high no matter what you cut out — it may not simply be your family's shared cooking and habits. It may be a named, inherited condition called familial hypercholesterolaemia. That is a genuinely different thing from cholesterol that drifts up with age, weight and diet, and the difference is worth understanding rather than shrugging off as "just us".

The distinction matters because the two lead to different places. "Just us" suggests something you manage at the food shop and the gym. A diagnosis suggests something a doctor should be treating, that your parents, brothers, sisters and children should be checked for, and that behaves in a very particular way when you apply for life insurance. Most people who have familial hypercholesterolaemia — usually shortened to FH — have never been told they have it. They assume high cholesterol is normal for their family, because within their family it is.

So the honest answer to "is that just us, or is it a diagnosis?" is that it could be either, and there is a real test that tells them apart. This article explains what FH is, how it is found, why it is so often missed, and — because you may be reading this with an application open in another tab — exactly how an inherited cholesterol condition sits on a life insurance form.

The short answer: it may have a name

High cholesterol is common, and most of it is what doctors call polygenic or lifestyle-related: the product of many small genetic effects added to weight, diet, alcohol, smoking and inactivity. It responds to changes in those things, and it tends to climb gradually with age. That is the version most people picture when they say cholesterol runs in the family, and shared habits genuinely do run in families alongside shared genes.

Familial hypercholesterolaemia is not that. It is a single-gene condition, passed down directly, that impairs the way your body clears LDL — the harmful form of cholesterol — out of the blood. Someone with FH has been walking around with a raised LDL since childhood, not since their thirties. Because the level has been high for so much longer, the risk it carries builds up earlier, which is why FH is associated with heart problems at ages that would otherwise be surprising.

The tell is the pattern. Cholesterol that is high in one person can be lifestyle. Cholesterol that is high in a parent, high in a sibling, high in you, and marked by an early heart attack or early death somewhere in the close family, starts to look like something being inherited in a straight line. That pattern is the thing a doctor is looking for, and it is the thing that should prompt the question this page is about.

What familial hypercholesterolaemia actually is

FH is caused by a fault in one of the genes involved in removing LDL cholesterol from the bloodstream, most often the gene for the LDL receptor. If you inherit one faulty copy — the common form — your LDL sits high from birth regardless of how carefully you eat. It is inherited in a dominant pattern, which in plain terms means each child of an affected parent has a one in two chance of inheriting the same fault. That is why it marches down through a family so visibly, appearing in generation after generation.

Because the cholesterol has been elevated since childhood rather than midlife, the arithmetic of exposure is different. It is the years multiplied by the level that does the damage to arteries, and FH quietly adds decades to that sum before anyone thinks to look. Untreated, that is what brings heart disease forward into a person's forties and fifties. Treated, the picture changes substantially — which is the single most important thing to hold on to, because FH is one of the more treatable inherited conditions there is.

None of this is a reason to panic at a single raised reading. One high number on its own is not FH. What raises the possibility is a very high LDL specifically, combined with the family history, and sometimes with physical signs that a doctor knows to check for.

The condition most people who have it have never been told about

Here is the part that surprises people. FH is not rare, and yet it is one of the most under-diagnosed serious conditions in the country. Current estimates put it at roughly one in 250 people. If that figure is right, most towns contain thousands of people carrying it, the great majority of whom have no idea, because their high cholesterol has been quietly filed under "runs in the family" and never investigated as a specific condition.

Source: National Institute for Health and Care Excellence (NICE), guidance on familial hypercholesterolaemia (identification and management).

The gap between how many people are thought to have FH and how many are actually recorded as having it in their GP notes is wide. Only a fraction of the expected number are formally diagnosed. That under-recording is not a filing quirk — it is people going undiagnosed and therefore untreated through exactly the years when treatment does the most good. If your family's high cholesterol has never been named as anything more specific than "our cholesterol", you may be looking at precisely that gap from the inside.

This is the reason the question is worth asking out loud with a GP rather than accepting the family shrug. The condition is common enough that it is worth ruling in or out, treatable enough that the answer changes what happens to you, and missed often enough that no one may have joined the dots across your relatives before.

How it is found and confirmed

Diagnosis usually starts with the numbers and the story rather than with a DNA test. A doctor looks at the LDL cholesterol level — a markedly high one raises suspicion — and sets it against the family history: high cholesterol in first-degree relatives, and any early heart disease among them. There are recognised clinical criteria that pull those threads together into a likelihood of FH.

Sometimes there are physical signs. Long-standing very high cholesterol can deposit in tendons, thickening them, and can show around the eyes. A clinician knows to look for these; you would not necessarily notice them yourself. Where the clinical picture is strong, a DNA test can confirm the specific faulty gene, though a diagnosis of FH does not always require the gene to be pinned down.

Once one person in a family is diagnosed, the guidance is clear that close relatives should be offered testing too. This is called cascade testing: working outward from the diagnosed person to parents, siblings and children, because each has a one in two chance of carrying the same fault. It is one of the more efficient things the health service does, because a single diagnosis can flag a whole branch of a family who can then be treated before anything goes wrong.

Guidance and services differ across the UK. The NICE guidance applies in England and is generally followed in Wales, while Scotland works to its own clinical guidelines and Northern Ireland to its own arrangements, so exactly how cascade testing is organised where you live can vary. The underlying point does not: if FH is confirmed in one relative, the rest of the close family have good reason to be checked.

What it means when you apply for life insurance

This is where inherited cholesterol behaves differently from a plain lifestyle reading, and where the rules are more in your favour than you might expect.

A predictive genetic test result — a DNA test that tells you that you carry an FH fault before you have any diagnosis based on your own cholesterol — cannot be asked for by a UK life insurer. Under the industry code that governs this, insurers do not ask for and you do not have to volunteer a predictive genetic result. That protection covers the DNA test itself. The only genetic condition currently outside it is Huntington's disease, and only above a high level of cover, which we cover separately in the £500,000 line in Huntington's life cover. FH is nowhere near that exception.

Source: Association of British Insurers (ABI), Code on Genetic Testing and Insurance, which sets the £500,000 life cover threshold and the single Huntington's exception.

What an insurer can ask about is your ordinary medical history. If you already have a diagnosis of FH recorded, that is a medical fact, not a protected gene result, and it is disclosable if the application asks about your conditions. So are your cholesterol readings, and so is any treatment you take, such as a statin. The line to hold in your head is this: the predictive DNA result is off-limits to them; a diagnosis, the numbers behind it, and what is being done about it are ordinary medical facts you answer honestly when asked.

People sometimes worry that an insurer will go rummaging through everything. There are limits to what they see and how, and we set those out in what a life insurer can and cannot see in your medical record. The short version is that they work from what you disclose and, with your consent, from a targeted report, not from an open-ended trawl.

Treated and well controlled is a different picture

The most useful thing to understand about applying with FH is that underwriters are not looking at a label, they are looking at control. FH that has been diagnosed, is being treated, and shows cholesterol brought down to target is a fundamentally different risk from high readings that have never been addressed. The condition is the same; the trajectory is not.

That is why two people from the same family, carrying the same inherited fault, can be assessed quite differently. One has been diagnosed, takes a statin, has regular reviews and a controlled LDL. The other has never been tested, has readings left to run, and no treatment on record. To an underwriter those are not the same application, even though the genetics behind them are identical. It is one of the clearest examples of why getting diagnosed and treated is not something that counts against you with insurers — if anything, being on top of it is the stronger position.

Outcomes still vary between companies, because each insurer weighs cardiovascular history in its own way. That variation is a good reason to compare rather than assume the first answer is the market's answer. If you want cover priced against your actual health rather than your worst fear about it, you can get life insurance quotes and have an FCA-authorised broker take the full picture into account, including well-controlled FH.

What to do if the pattern is in your family

If reading this has made the pattern in your own family suddenly legible, the sequence is straightforward. Ask your GP to look at your cholesterol in the context of the family history rather than in isolation — the family part is what turns a number into a question worth chasing. If you already have a relative with a confirmed FH diagnosis, say so, because that is exactly the trigger for cascade testing and it changes how seriously a single reading is taken.

Do not delay getting checked out of a fear that a diagnosis will harm a future insurance application. It will not work the way that fear imagines. The protected part — the predictive gene result — stays protected either way, and being diagnosed and treated puts you in a better underwriting position than leaving high readings unexamined, not a worse one. The clinical benefit of catching and treating FH early is real and it is yours to gain.

It is also worth being clear about why cover matters here at all, beyond the abstract. For most people the reason to hold life insurance is a mortgage and the people who live under it; a home is not the clean asset it looks like, because a house left in a will comes with the mortgage still attached to it. FH is one of the conditions that makes people think about that early, precisely because it brings cardiovascular risk forward rather than leaving it comfortably in old age. When you do come to apply, it is worth knowing in advance how far back the family history question on the form actually reaches, so that you answer the question they are really asking rather than the one you fear.

You can read the wider picture on inherited risk and what insurers may and may not ask in our guide to family history, inherited risk and the odds. For clinical information on cholesterol and FH itself, the NHS pages on high cholesterol are a reliable, non-commercial starting point.

Frequently asked questions

Why does high cholesterol run in my family?

Shared diet and weight play a part, but a strong inherited pattern — high readings in several relatives, sometimes present from childhood, alongside early heart disease — can point to familial hypercholesterolaemia. FH is an inherited condition affecting how the body clears LDL cholesterol. It is estimated to affect around one in 250 people and is widely undiagnosed, so a family that has always assumed its high cholesterol is normal may in fact be carrying a specific, treatable condition.

How is familial hypercholesterolaemia diagnosed?

Usually by a markedly high LDL cholesterol level considered together with the family pattern, sometimes supported by physical signs such as thickened tendons, and confirmed where appropriate by a DNA test — though a diagnosis does not always require the gene to be identified. Once someone in a family is diagnosed, the guidance is to offer cascade testing to close relatives, because each parent, sibling and child has a one in two chance of carrying the same fault.

Does FH affect a life insurance application?

A predictive DNA result cannot be asked for by a UK insurer, so a gene test taken before any diagnosis stays protected. A diagnosis you already have, your cholesterol readings and any statin or other treatment are ordinary medical facts and are disclosable if the form asks about them. Importantly, treated FH with well-controlled cholesterol is assessed very differently from untreated high readings, so being diagnosed and on top of it tends to help your position rather than harm it.