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Home , Blood lipids, Saturated fat, Triglyceride

Blood Explained

HEART UK – The Charity providing expert support, education and influence 2 | Fats in the At risk of ? | 3

Fats in the blood At risk of cardiovascular disease?

Fats that circulate in the blood are called . Very low density (VLDL) transport Cardiovascular disease (CVD) is the medical Blood pressure is a measure of the resistance Cholesterol and are both lipids. mainly triglycerides made by the to where name for circulatory diseases such as coronary to the flow of blood around your body. It is They have essential roles in the body. In excess they are either used to fuel our muscles or stored heart disease (CHD), , mini stroke (transient measured in millimetres of mercury (mmHg). Your they are harmful. for later use. ischaemic attack or TIA), angina and peripheral doctor or nurse will measure both your systolic vascular disease (PVD). You are more likely to (upper figure) and diastolic (lower figure) blood Cholesterol is needed to build walls and Low density lipoproteins (LDL) carry most of the develop CVD the more risk factors you have. pressure. About a third of adults have high blood to make hormones and vitamin D. Some of our cholesterol in our body from the liver to the cells pressure. If untreated it increases the risk of cholesterol comes from the we eat; but most that need it. The cholesterol that is carried on LDLs There are two types of risk factors: heart attack and stroke. High blood pressure is is made in the liver. When broken down cholesterol is called LDL-cholesterol or bad cholesterol. Fixed risk factors – these include your age, usually diagnosed when a number of readings are is used to make acids which help us to digest High density (HDL) plays a vital family history and being a man. You cannot do made above 140/90mmHg. our food. role in taking excess cholesterol, away from cells anything to change these risk factors. Type 2 can affect your heart health. Triglycerides are fats which are found in and artery walls, back to the liver for disposal and Risk factors you can change: This is because it can affect the quantity and our food. When we eat, any in our food is recycling. Having healthy HDL levels means less quality of fats (cholesterol and triglycerides) absorbed by our gut (intestine). It is then moved cholesterol will build up in the artery wall. • Unhealthy cholesterol (and ) levels in your blood. Usually people with type 2 around the body, in our blood, as triglycerides. The cholesterol that is carried on HDLs is called in the blood diabetes have increased triglyceride levels (due The liver also makes triglycerides. They provide HDL-cholesterol or good cholesterol. • Smoking to an increase in VLDLs), low levels of HDL the energy that is needed by our muscles and We also refer to intermediate density • High blood pressure and smaller sized LDL particles. This pattern organs and help keep us warm. lipoprotein (IDL) in this booklet. These are • increases the risk of developing heart disease. cholesterol and triglyceride rich particles. • A large waistline What are lipoproteins? A large waistline is a sign that you are storing fat Cholesterol and triglycerides cannot circulate Unlike the levels of VLDL, LDL, There is a lot you and your doctor can do to lower inside and around your vital organs. Doctors know loosely in the blood, so they travel in “round HDL, IDL and cholesterol change very little after your risk from these. this fat can increase your risk of diabetes and heart a meal. The levels of these lipoproteins usually problems. We talk more about this on page 5. parcels” called lipoproteins. Lipoproteins contain Stopping smoking can make a big difference reflect longer term diet and lifestyle habits. a special mix of fats and which allow to both your short and long term health. People them to flow freely in the blood. B is the key for who smoke are more likely to have a stroke, heart APOLIPOPROTEIN A The are four main lipoproteins (sometimes called chylomicrons, VLDL and LDL. attack or breathing problems when compared to someone with the same risk factors who does ). They vary in size, content and Apolipoprotein A is the key protein for HDL. not smoke. On average smokers die 15 years CHOLESTERYL how tightly they are packed (density). Lipoprotein (a) or Lp(a) is a large “sticky” earlier than non-smokers. Toxins in cigarette Chylomicrons are the largest. They carry lipoprotein particle made in the liver. The amount smoke put a bigger strain on the heart - making TRIGLYCERIDE triglycerides from the intestine to the tissues of Lp(a) in our blood is largely decided by our it beat faster, increasing the risk of blood clots UNESTERIFIED where they are needed as a source of energy. genetic makeup. Doctors are interested in Lp(a) and damaging the inside of your blood vessels CHOLESTEROL The number of chylomicrons in the blood because high levels increase the risk of heart and (arteries). Smoking also lowers your protective increases after a meal and then slowly decreases. circulatory disease. HDL-cholesterol. You can cut your risk of CHD in half, in just one year, by stopping smoking. The HDL lipoprotein Words in red are featured in our glossary on page 14.

Cholesterol and triglycerides have essential roles in the body. Having a , not smoking, being active and keeping your waistline in check are Lipoproteins - like LDL and HDL - carry cholesterol and triglycerides around in the blood good for everyone and can help you keep healthy. 4 | How your heart works Why your liver is important | 5

How your heart works Why your liver is important

The heart RIGHT CORONARY ARTERY The liver plays a central role in controlling the LEFT CORONARY amount of fat in your blood. The heart, blood vessels and blood make up our ARTERY . The heart is a muscle which Liver cells have special “hooks” on them that can never stops beating, it pumps blood around the CIRCUMFLEX remove LDL cholesterol from the blood. These body. The left side pumps and ARTERY are called LDL receptors. rich blood to the brain, muscles, organs, and Most of our cholesterol is made in the liver. every cell in the body. The right side of the heart The liver is also the major site for changing is slightly smaller and returns blood to the lungs to excess , proteins and into fatty be topped up with oxygen. acids and triglycerides, which are then either used The heart has its own blood supply which comes for energy or stored for later. from the coronary arteries. These divide many Any fat that builds up in the liver, can damage it. times to provide oxygen and to every MARGINAL Fatty liver can be caused by drinking too much part of the heart muscle to help keep it healthy ANTERIOR ARTERY INTERVENTRICULAR alcohol or by eating too much. It is common and pumping normally. ARTERY POSTERIOR INTERVENTRICULAR ARTERY in people who carry too much fat around their waistline. If you have too much fat in your liver Heart disease The heart and the coronary arteries it won’t work as well as it should - a sign could Problems occur when any one of these arteries be too much cholesterol, triglycerides or in become narrowed due to the slow build-up of What is ? your blood. Most people won’t know they have a fatty material (called plaque or ). (ather-o-scler-o-sis) fatty liver. This process - called atherosclerosis - causes Atheroslcerosis is a very slow process, coronary heart disease (CHD). Sometimes BRAIN an artery can become so narrow it cannot deliver happening over many years. It can start very enough blood. This results in warning symptoms early in life and results in the build up of fatty TONSIL material in the linings of your blood vessels. such as chest pain – we call this stable angina. THYROID

When these fatty deposits become very large These fatty deposits start when the blood vessel or extended they may burst. Just like when you lining becomes damaged. This makes it easier for graze your knee, a blood clot and then scarring cholesterol (carried on lipoproteins like LDL) to LUNGS forms over the damaged area. Over time this stick on and build up more rapidly. HDL lipoproteins HEART can remove cholesterol from these deposits. damage may partly or completely block the artery. STOMACH When this happens it is called acute coronary Reducing your LDL cholesterol, increasing your HDL LIVER SPLEEN syndrome (ACS), unstable angina or heart cholesterol and reducing other risk factors can help KIDNEY attack. A heart attack is sometimes referred to slow down the process of atherosclerosis. as a or MI. Major organs in the body

Heart facts • Your coronary arteries supply your heart muscle with oxygen and nutrients • Your liver controls the amount and type of fat in your blood • A heart attack happens when one of these arteries become blocked • Fatty liver happens when your body stores fat inside your liver 6 | clinics How blood fats cause heart disease | 7

Lipid clinics How blood fats cause heart disease

Lipid clinics provide specialist help and advice Checking your blood fat levels Having enough cholesterol and triglycerides is to those who have raised such as vital for health. But sometimes we have too much Your doctor can check the amount of cholesterol cholesterol and triglycerides and who may have, cholesterol, triglycerides, and the lipoproteins that and triglycerides in your blood. They are or be at high risk of developing, CVD. carry them, in our blood. High cholesterol and/or measured in millimoles per litre (mmol/L). triglycerides can run in families. What you eat and You may be referred to a lipid clinic if: Sometimes, but not always, you will be asked to drink, your weight, how active you are and if you fast overnight before a test. Lipid clinics can also • Y our GP thinks you may have a blood fat smoke can also have an effect. carry out other more specialised tests to help condition that is passed down through families High triglycerides and diagnose and manage your condition. Your doctor will be concerned if, in your blood: • Y ou have too much cholesterol or triglyceride low HDL-cholesterol in your blood • Y ou have too much cholesterol or What is a healthy level of cholesterol? People who have too much • Y ou are having problems when taking a triglyceride in the blood often have Healthy adults should aim for a: • You have too little HDL-cholesterol or another cholesterol lowering medicine too little HDL-cholesterol too. This • Total cholesterol below 5mmol/L • If you need a specialist test • Your triglyceride levels are high can run in families but usually it • Non-HDL cholesterol below 4mmol/L • You have high levels of Lp(a) Doctors working in lipid clinics have a variety happens in those who are obese, • HDL cholesterol above 1mmol/L (man) of names such as lipidologist, chemical If in addition: have type 2 diabetes, or who drink or above 1.2mmol/L in a woman too much alcohol. High triglycerides pathologist or clinical biochemist, or they • You have other risk factors (see page 3) and low HDL cholesterol can increase may be a cardiologist, diabetologist or What is a healthy level of triglycerides? endocrinologist. Their job is to find people with Too much cholesterol the risk of heart disease. Very high Healthy adults should aim for a: triglycerides may cause pancreatitis, blood fat conditions and to decide on the right On page 2 we talked about how cholesterol • triglyceride below 1.7mmol/L a very painful and serious problem of treatments. travels around the blood inside lipoproteins • Non-fasting triglyceride below 2.3mmmol/L the gland in the abdomen. Lipid specialists may work with dietitians and lipid called LDL, HDL, VLDL, IDL and chylomicrons. nurses, and alongside your GP, to help give you If you have existing heart disease, or are at Up to now most doctors have referred to LDL the support you need to manage your condition. high risk of getting it, your doctor may advise cholesterol as “bad” cholesterol. But experts now you to aim for lower levels of cholesterol and say it is not that simple. They now believe it is the triglycerides. sum of all the cholesterol that is carried on LDL, VLDL, IDL and chylomicrons that is damaging. It is best to discuss this with your doctor when We usually refer to this as non-HDL cholesterol. they review your treatment. Any target levels your doctor suggests will depend on your diagnosis, LDL + VLDL + IDL + Chylomicrons = non HDL your age and any other risk factors you have. Talk cholesterol = damaging cholesterol to your doctor about the levels you should aim for. All the lipoproteins that make up non HDL- Unhealthy patterns of cholesterol and triglycerides cholesterol have the same characteristic protein in the blood are often referred to as dyslipidaemia. - apolipoprotein B (apoB). So lipid experts will sometimes find it helpful to measure the amount of apoB in the blood.

Lipid clinics Lipid clinics see people who are referred for specialist help and advice by their GP. Lipid clinic doctors and nurses are experts in treating blood fat conditions. 8 | Lipid conditions Lipid conditions | 9

ma ho nt Inherited lipid conditions a x n o d n e T Here we describe some of the main inherited Familial Combined Hyperlipidaemia (FCH) From the time they are born, people with FCS will blood fat conditions. is an inherited condition that affects about 1 in have very high triglyceride levels - but these may 100 people. It happens when the body makes too not be spotted until they are much older. Signs Familial Hypercholesterolaemia (FH), much VLDL and apolipoprotein B. People with include recurrent abdominal pain, fat-filled spots usually referred to as FH, results from inheriting FCH usually have higher than normal levels of known as ‘eruptive xanthoma’, and attacks of acute an altered gene that causes very high blood cholesterol and triglycerides in their blood. pancreatitis. The main treatment is diet, which must cholesterol. “Familial” means that it runs in be as low in fat as possible. families. “Hypercholesterolaemia” means high This condition is not as well understood as FH, blood cholesterol. The type of cholesterol that is but is also associated with early CVD. Raised Type 3 Hyperlipidaemia is also known as increased in FH is LDL-cholesterol. cholesterol and triglyceride levels will not be dysbetalipoproteinaemia or remnant particle a sm present in childhood, and may not appear until hyperlipidaemia. la e As many as 1 in 250 people may have FH. It th n people are in their twenties, thirties or even older. a increases the risk of early CVD if not found This condition is thought to occur in 1 in 5000 people, X FCH is more likely to present early in those adults and treated. A pattern of early death from heart with a 1 in 4 chance of inheriting it from a parent. who are overweight or have an unhealthy diet and disease in close family members is a sign that FH Both cholesterol and triglyceride levels are high. lifestyle. Checking apolipoprotein B levels can be might affect your family. Some people with Type 3 have physical signs such useful when making a diagnosis. as yellow deposits (xanthoma) which appear in the Total cholesterol levels in adults are normally Polygenic Hyperlipidaemia is the name given creases of the hand (palmar creases) and at the above 7.5mmol/L and LDL-cholesterol above to conditions caused by inheriting a mixture of elbows and knees (eruptive xanthoma). 5 mmol/L, with normal triglyceride levels. Some “common LDL-cholesterol” and/or “triglyceride” people will have physical signs of FH and these The pattern of lipoproteins for Type 3 is very raising genes. On their own each of these can help doctors to make a diagnosis. Tendon different to other inherited lipid conditions and is key genes would have little effect on blood fats but xanthoma and corneal arcus (before the age of to making a diagnosis. There are higher levels of together they can cause big increases. The term us rc 45) are definite signs of FH. VLDL and IDL particles, which appear in the blood l a a “polygenic” means the influence of many genes. e n r after meals and which contain both cholesterol and o Almost all people with FH will have heterozygous Polygenic hypercholesterolaemia is quite C triglyceride. LDL-cholesterol and apolipoprotein B FH, inheriting a single gene alteration from one common and can be made worse, or better, by levels are often low. parent. If you have this form of FH then each of what you eat and drink and how active you are. your children have a 1 in 2 chance of inheriting FH. Unless treated, people with type 3 are at high risk Familial Chylomicronaemia Syndrome (FCS) of CHD and peripheral vascular disease (PVD). Homozygous FH is rare (up to 1 in 250,000) and also known as lipoprotein deficiency PVD is the name given to changes in the major happens when a baby inherits a gene alteration (LPLD) is a very rare genetic problem that affects arteries supplying the legs, arms and major organs. from both parents, resulting in extremely high about one person in a million people. It can result in a poor supply of blood to the legs. levels of cholesterol. People with FCS have very high triglyceride One of the main symptoms of PVD is pain in the legs Some people with FH have too much Lp(a) in levels. This is because they lack lipase, the when walking. a om their blood and this should be checked. If yours is enzyme that clears triglycerides from the blood th an x e high, your doctor will want to discuss how best to after a meal. v ti p u manage this. r E

Checking for lipid conditions • Looking for telltale signs on the body Lipid conditions are usually diagnosed by a combination of: • Taking a family history • Measuring blood fats and other special tests • In some cases, doing a genetic test 10 | Diet and lifestyle 11

Diet and lifestyle

Everyone can benefit from eating well and having Certain can actually lower cholesterol if a healthy lifestyle. And for people with raised eaten regularly. These include: cholesterol and triglycerides this is very important. • Foods rich in soluble fibre (, , beans, Being physically active peas, lentils, vegetables, fruits) • Nuts (choose unsalted varieties) Being active is a great way to exercise your heart, • Plant proteins such as soya and quorn boost your levels of HDL-cholesterol, manage your weight and reduce your waist circumference. • Dairy foods fortified with plant sterols and It also helps you look and feel great. Adults stanols* should aim for at least 150 minutes a week. The Certain foods can raise triglycerides and these exercise you choose should get you slightly out should be either limited or avoided by people with of breath. If you haven’t exercised for some time raised triglycerides: check with your doctor first. • Sugar , foods containing refined, added or Eating well “free sugars” A heart-healthy diet is rich in fruit and vegetables, • Alcohol whole grains, pulses, nuts, seeds, fish and See the HEART UK website for more information vegetable proteins such as soya. Eating well is an on how to lower cholesterol and triglycerides. important part of your treatment. It can help you Why not try HEART UK’s Ultimate Cholesterol to control blood cholesterol and triglyceride levels. Lowering Plan (UCLP©), our Low Fat Eating Plan or call us for a copy of our popular Diet Simple fat swaps Guide. Dietary fats fall into two main groups: saturated and unsaturated. Most is solid at What about alcohol? room temperature and found mainly in foods from It is best to ask your doctor about drinking alcohol. animals, such as , dairy products, , If they advise it is ok then try to limit alcohol to no and . It is also found in hard , more than 14 units spread across the week with and palm and in processed foods such several alcohol free days in between. If you are as pies, pastries, cakes and puddings. pregnant you should not drink alcohol at all. We all need a little saturated fat, but too much *Foods fortified with plant sterols and stanols are not suitable increases blood cholesterol levels, so an during pregnancy or when breastfeeding. Children with an important part of a heart-healthy diet is to limit inherited blood fat condition may benefit from these foods saturated fat. Instead choose more unsaturated but check with your doctor or dietitian first. fats (nuts and seeds; vegetable, olive and oils; soft vegetable spreads, oily fish, ).

Five important guidelines for a heart-friendly diet 3. Choose meat free meals (fish, nuts, pulses, soya, quorn) more often 1. Swap foods high in saturated fats for those rich in unsaturated fats 4. Limit food and drinks high in sugar or alcohol 2. Eat more whole grains, nuts, pulses, vegetables and fruit every day 5. Cook more meals from scratch, and limit takeaway and processed foods 12 | Medical treatments 13

Medical treatments

Most of the blood fat conditions we talk about in Ezetimibe: Ezetimibe blocks the absorption of this booklet are treated with one or more of the cholesterol and bile acids in the intestines. It following medicines. is often given to help people who are already taking a statin but who need a little extra help to work by slowing down and reducing the reach their cholesterol targets. Ezetimibe may amount of cholesterol our bodies make. also be prescribed for those unable to tolerate For most people statins are safe and well statin therapy. tolerated - but a few people may experience PCSK9 inhibitors are very good at lowering general muscle aches which should be reported cholesterol but they are not yet widely available. to your doctor. Statins should not be used if you They are given by injection once or twice a are planning to have a baby, are pregnant or month and appear to be well tolerated. Talk to breastfeeding. your lipid specialist about whether they may be may be useful when triglycerides are suitable for you. raised. Used alone fibrates can raise LDL- Omega 3 fish oils (1-4g daily) reduce plasma cholesterol levels. For this reason they are usually triglyceride levels in some lipid conditions. They given alongside a statin. You are most likely to work by reducing VLDL production in the liver. be prescribed a if you have triglyceride To get the equivalent of 1g of fish per day you levels above 10mmol/L. They are well tolerated would need to eat three good portions of oily but should not be used during pregnancy or by fish per week. Fish oils are prescribed less often individuals with significant liver or kidney disease. these days and are thought to be less effective Resins ( sequestrants) come as than a fibrate. powder, granules or tablets. The powder and Lipoprotein apheresis: Lipoprotein or LDL granules are taken by mixing with water, fizzy apheresis is not a drug, it is a treatment similar drinks, fruit juice or yoghurt. They work by to kidney dialysis. A person is connected to a preventing the re-absorption of bile acids in the machine that removes LDL-cholesterol, Lp(a) intestine, which means that more cholesterol is and triglycerides from their blood. The ‘cleaned’ used up in replacing them. Resins are safe for blood is then returned to them. The process children and pregnant women because they are takes about 3 hours and has to be repeated at not absorbed into the body. Resins can cause weekly or fortnightly intervals. Only a few people wind and constipation which can be a problem will need this treatment - it is costly to do and so for some people. is only available in a few specialised centres. It may be considered when people still have a high cholesterol level despite taking all available or tolerated medicines and a healthy diet.

Statins and Ezetimibe can be prescribed by your GP but the other medicines are usually only prescribed by specialists. From time to time new medicines and treatments are developed for people with raised blood fats. 14 | At a glance guide to medical terms

Guide to medical terms HEART UK – The Cholesterol Charity

Acute coronary syndrome (ACS): The term for HDL-cholesterol: Good cholesterol, it takes We hope this booklet has helped to explain what blood fats are, how they move any condition brought on by sudden reduced blood excess cholesterol back to the liver where is can be around our bodies, why too much can be harmful and how healthy living and flow to the heart. disposed of. taking any medicines or treatments your doctor prescribes can help. Angina: Usually severe pain in the chest, sometimes Homozygous: When someone has two copies of HEART UK is the only charity in the UK dedicated to providing expert support, spreading to the shoulders, arms, and neck, caused a disease-causing altered gene - one from each of guidance and education for people with blood fat conditions and their relatives. by too little blood getting to the heart muscle. their parents. Apolipoprotein - see lipoprotein. Hypercholesterolaemia: High blood cholesterol. Call/email our Cholesterol Helpline Literature orders Atheroma (plaque): Fatty deposits inside the Hyperlipidaemia: High levels of cholesterol and 0345 450 5988/[email protected] Call 01628 777046 or email us on artery wall. triglycerides in the blood. [email protected] Atherosclerosis: The process by which arteries Hypertriglyceridaemia: High levels of A free and confidential service offering information on cholesterol and an become narrowed over many years. triglycerides in the blood. General enquiries opportunity to talk things over with qualified Bile acids: Used in fat , these are made LDL-cholesterol: Most cholesterol in the blood is nurses and dietitians. 01628 777046 from cholesterol. in this form. It is also referred to as bad cholesterol. Cholesterol: An essential building block, needed Lipids: The name for fats in the blood. Donate Go online for growth and good health. Lipoproteins (apolipoproteins): The fat and Please help to fund our work. All our Advice and lots more information is CHD – Coronary heart disease: When one or more protein parcels that carry fats around the body. materials are free, but you can make a available on our website. Check out our of the coronary arteries become narrowed or blocked. Lp(a): A large “sticky” lipoprotein; high levels donation towards our work via our website. frequently asked questions, recipe ideas, Chylomicrons, VLDL, LDL, HDL, IDL: Types of increase the risk of heart and circulatory disease. what your cholesterol and triglyceride lipoproteins that carry fat around in the blood. MI – Myocardial Infarction: A heart attack. Raise funds numbers mean and sign up to our free CVD – Cardiovascular disease: A collective term monthly e-newsletter for more facts and tips PVD: Peripheral vascular disease – partial or There are many ways you can raise funds for circulatory diseases such as coronary heart to help you and your family stay healthy. complete blockage in the main arteries that supply for HEART UK. Visit our website for more disease (CHD), stroke, mini stroke and peripheral the legs, arms and major organs. information. vascular disease (PVD). Polygenic: The small effects of many genes. Visit our website Dyslipidaemia: A general term for an altered and Saturated fat: The type of fat that can increase National Cholesterol Month You can find out more on our website at unhealthy pattern of blood fats. www.heartuk.org.uk your cholesterol, it is found mainly in animal foods. October is National Cholesterol Month – a Familial: Used to describe conditions that run in Triglycerides: Another name for fat, it is found whole month devoted to raising awareness families. in foods and in the blood. Triglycerides are made and funds for HEART UK. Fatty liver: Fat becomes stuck in the liver. It can from three fatty acids and one molecule stop the liver working properly. joined together. Heterozygous: When someone has only one copy Unsaturated fat: The type of fat that does not of a disease-causing altered gene - coming from increase your cholesterol level. Most of the fat we either their mum or their dad. eat should be unsaturated.

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