Too much cholesterol in your blood can increase your risk of heart disease and other cardiovascular diseases. Catherine Collins explains the different types of cholesterol and what you can do to help keep your cholesterol levels healthy
It’s been 40 years since blood cholesterol was first linked to heart disease, but do you know exactly what cholesterol is – or how it affects you? According to Heart UK, 6 out of 10 adults in the UK have raised levels of blood cholesterol. A high blood cholesterol can increase your risk of heart disease, stroke and other circulation problems.
According to Heart UK, 6 out of 10 adults in the UK have raised levels of blood cholesterol
CHOLESTEROL – WHAT IS IT?
Cholesterol is a waxy substance essential for life. Cholesterol is made into hormones such as oestrogen, testosterone and vitamin D. Our liver uses cholesterol to make bile salts, stored in the gallbladder and released when we eat fatty foods.
Cholesterol helps transport fats around the bloodstream. As fat and water don’t mix, we ‘coat’ fats and oils with an outer layer of protein and cholesterol. These coated ‘fat balls’ are called ‘lipoproteins’. A cholesterol blood test measures cholesterol attached to these lipoproteins.
Large, fat-rich balls are called ‘low density lipoproteins’ or ‘LDL’ for short. LDLs (or LDL-cholesterol) are known as ‘bad’ cholesterol because they can drop cholesterol and fat into the artery wall on their travels. This starts local inflammation which results in long term damage and formation of an atheroma – a lump that narrows the artery and affects blood flow. In contrast, ‘high density lipoproteins’ (or HDL-cholesterol), help protect arteries from damage by rolling up fatty deposits and safely returning them to the liver for processing, preventing atheroma formation. HDL’s are often called ‘good cholesterol’. For heart health you want your LDLs to be Low, and your HDLs to be High.
Triglycerides, rich in fat, are often measured alongside cholesterol. High blood triglycerides are another risk for heart disease and stroke and can cause the painful condition pancreatitis. If your triglycerides are high, reducing sugar and alcohol intake and eating more omega-3 ‘fish oil’ type fats will lower blood levels, as will losing excess weight.
Keeping your blood cholesterol within a healthy range helps reduce your risk of heart disease and other circulation problems.
WHAT IS A HEALTHY CHOLESTEROL LEVEL?
Check the table on page 54 for your healthy cholesterol level. If you have high blood pressure, diabetes or rheumatoid arthritis, your risk of cardiovascular disease is higher.
HOW TO IMPROVE BLOOD CHOLESTEROL RESULTS
Keep total fat intake to less than a third of your daily calorie intake. For an average 2000 calorie diet this equals around 70g of fat daily.
Too much saturated fat increases LDL cholesterol, so limit to less than 20g a day. Foods rich in saturated fat include butter, lard, palm oil, coconut cream and oil, fatty and processed meats (like sausages, liver sausage, pate), cheese, pastries, croissants, cakes and biscuits. Trans fat is especially damaging. It’s found mainly in ‘shaved’ spit-roasted meats (like doner, shawarma and gyros) and foods cooked in very hot oil.
Choose unsaturated fats for better heart health. Polyunsaturated fats (PUFA) include sunflower, corn and soya oils, and foods made with these. They lower ‘bad’ cholesterol and boost ‘good cholesterol’ levels. Omega-3 polyunsaturated fats from oily fish are particularly heart-healthy. Try to include 1-2 portions (like salmon, tuna, mackerel, sardines) into your weekly diet. Omega-3 fats are also found in plant based foods, like flaxseed (linseed) and walnut oils. Mono-unsaturated fats (MUFA), found in olive and rapeseed oils and spreads are healthy choices too. Rapeseed oil also provides omega-3 fats.
Shellfish, eggs, fatty and processed meats and offal are rich in cholesterol but it’s the amount of saturated fat in these foods, not their cholesterol content, that raises blood cholesterol. So keep shellfish and eggs on your menu – but limit the liver pate and sausages.
FOODS THAT HELP LOWER CHOLESTEROL
Oats and barley contain a gel-like ‘soluble fibre’ called beta glucan. This binds cholesterol and bile salts to reduce absorption. Oats and oat-based foods can make a nutrition claim for a cholesterol-lowering effect if they provide at least 0.75g of beta glucan per portion – a quarter of the optimum 3g of beta glucan recommended daily. A quarter cup of uncooked pearl barley, a useful addition to homemade soups, provides 2.5g of beta glucan. Chickpeas, lentils and beans are great for cholesterol lowering, too. Soya protein is especially good for cholesterol control, whether taken as soya milk or tofu.
Nibble on raw, unsalted nuts. They’re low in sugar and rich in healthier plant oils, vitamin E, soluble fibre and plant sterols. They’re high in calories though so limit your daily intake to a handful – around 30g.
Fruit and vegetables are mainly low calorie and rich in vitamins and minerals that help stablise LDLs and protect your heart. Aim for your 5-A-Day from different coloured fruit and vegetables for best effect.
Too much saturated fat increases LDL cholesterol, so limit to less than 20g a day
‘FUNCTIONAL FOODS’ TO LOWER CHOLESTEROL
Stanols and sterol esters are natural plant substances added to dairy products and ‘mini’ drinks to lower cholesterol. They work by blocking the uptake of bile salts, increasing losses from the digestive tract. The liver then makes replacement bile salts, reducing ‘bad’ cholesterol levels by up to 10 per cent. If you use fortified dairy foods, you need to take them at each meal. Take the ‘one-a-day’ mini drink with the main meal of the day to ‘capture’ the most bile salts and maximise cholesterol lowering.
Red yeast rice extract (RYRE) is a fermented rice product used in Traditional Chinese Medicine to lower cholesterol. The active ingredient in RYRE is Monacolin K, identical to the cholesterol lowering medicine lovastatin. It is not recommended to take RYRE before speaking to your general practitioner.
HOW TO BOOST ‘GOOD’ CHOLESTEROL HDL
Exercise can boost HDL levels. Half an hour of exercise that leaves you slightly puffed, such as brisk walking, will lower LDL cholesterol and boost HDL cholesterol. Aim for 150 minutes a week for both heart and mind benefits.
Alcohol of any type, not just red wine, can boost HDL levels – but the quantity is important. Only 1-2 units is needed to have this effect – that’s a can of beer or a medium glass of wine.
A healthy, cholesterol lowering diet is rich in variety. It includes a moderate (not low) fat diet rich in fruits and vegetables, healthy vegetable oils, nuts, wholegrains, oily fish and modest amounts of dairy foods, meat, and alcohol.
Include fibre-rich foods in your diet: oats, beans, peas, nuts and seeds
Catherine Collins is a UK Registered Dietitian with an interest in heart health, digestive health and arthritis. A former NHS dietitian for over 30 years, she’s currently a WebMD UK dietitian and Media Spokesperson for the British Dietetic Association.