04 Oct Cholesterol Fact Sheet
Cholesterol is a fat-like substance that is needed for good health. Our body makes cholesterol, and it is also found in some of the foods we eat (mainly from eggs, meat and full fat dairy foods). Our bodies use cholesterol for a range of vital functions; to build cell walls, for the production of hormones, bile and vitamin D, and for many of the body’s metabolic processes. But too much cholesterol can damage our arteries and increase our risk of developing heart disease. Excess cholesterol builds up in the walls of the arteries forming patches called plaques. These can grow, become fibrous and calcified and narrow and can block the blood from flowing through the arteries, leading to angina (heart chest pain) heart attacks, strokes, kidney disease and leg ulcers.
Cholesterol in your body
To get to the cells in the body where it is needed, cholesterol travels around the body attached to special transportation molecules made of fat and protein called lipoproteins. There are two main types of these lipoproteins; high-density lipoproteins (HDL) and low-density lipoproteins (LDL). HDL cholesterol is sometime called ‘good’ cholesterol, because it removes cholesterol from your arteries and takes it back to your liver where it is broken down. LDL cholesterol on the other hand, is called ‘bad’ cholesterol. This is because LDL dumps cholesterol in your arteries, where it collects in the walls of the arteries and causes these plaques.
Testing for cholesterol
Blood tests can measure the levels of cholesterol in your bloodstream. HDL and LDL cholesterol can be tested for separately, or together (called a ‘total cholesterol test’). In a normal healthy person the total cholesterol should be no higher than 5.5 mmol per litre. Doctors can also test for another type of potentially harmful fat in your blood, called triglycerides. A test for triglycerides can be combined with HDL and LDL cholesterol in a test known as a known as a ‘lipid profile’.
It’s not the cholesterol in your diet, but the saturated fat
- In fact is not the cholesterol in your diet that cause high cholesterol in the body. The high cholesterol in your body comes from eating so-called ‘saturated’ fats in food. These fats, when ingested are broken down in the body and cause an increase in the body in LDL cholesterol, the bad cholesterol. These saturated fats (so-called because of their chemical makeup) come from animal sources such as meat and dairy products. Trans fats are another type of fat that cause an increase in LDL cholesterol, the ‘bad’ cholesterol. Trans fats are often used in making processed foods, such as cakes and biscuits, pies, pizzas and fast foods. So it is the trans fats and saturates fats in our diet that cause the cholesterol problems in the body.
What if your cholesterol is too high?
If your blood cholesterol is too high, you will need to take steps to lower it. This doesn’t necessarily mean taking medications. In fact, you can often lower your cholesterol to acceptable levels just by making eating a healthy diet that is low in saturated and trans fat.
Foods to avoid (those high in saturated fat and trans fats) include:
- cakes and biscuits
- fatty cuts of meat
- butter and full-fat dairy products
- processed meats like salami and sausages
- snack foods like chips
- most takeaway foods, especially those that are deep-fried
- foods containing coconut or palm oil
Some fats are actually healthy! Eating these healthy fats helps the cholesterol balance by decreasing the bad (LDL) and increasing the good (HDL) cholesterol. Foods rich in good (HDL) cholesterol include polyunsaturated oil (for example, sunflower or safflower oil).
Another way to avoid saturated and trans fats in your diet is to eat a diet that is high in fibre, and therefore low in fats.
Natural chemicals called sterols can also lower cholesterol levels; these are found in plant foods such as sunflower and canola seeds, vegetable oils, nuts, legumes, cereals, fruit and vegetables.
Thus, a high fibre diet low in saturated fat combined with exercise and physical activity can often lower your cholesterol to acceptable levels without the need for medications.
If these diet and lifestyle changes aren’t enough to lower your cholesterol levels, your doctor may recommend you take cholesterol-lowering prescription medications. However, a healthy diet and plenty of exercise are still important, even if you are taking medications.
To reduce your body’s cholesterol and stay healthy:
- Increase your daily intake (and variety( of fresh fruit, vegetables and wholegrain foods.
- Choose low or reduced-fat milk, yoghurt and other dairy products (but don’t cut out dairy foods altogether as they provide essential nutrients such as calcium).
- Eat lean meat (with fat trimmed off, or labelled as ‘heart smart’).
- Limit fatty meats, including sausages and salami, and instead choose leaner meats like turkey breast or lean chicken.
- Include fish (fresh or canned) at least twice a week.
- Replace butter and dairy blends with polyunsaturated margarine.
- Eat plenty of foods that are rich in fibre
- Eat food with healthy fats, such as nuts, legumes and seeds.
- Choose low fat dairy products and limit cheese and ice cream