Blood cholesterol level and its sequele

What Your Cholesterol Levels Mean

Your test report will show your cholesterol levels in milligrams per deciliter of blood (mg/dL). To determine how your cholesterol levels affect your risk of heart disease, your doctor will also take into account other risk factors such as age, family history, smoking and high blood pressure.

A complete fasting lipoprotein profile will show:

Your total blood (or serum) cholesterol level
Your HDL (good) cholesterol level
Your LDL (bad) cholesterol level
Your triglyceride level

Your Total Blood (or Serum) Cholesterol Level

Less than 200 mg/dL: Desirable
If your LDL, HDL and triglyceride levels are also at desirable levels and you have no other risk factors for heart disease, total blood cholesterol below 200 mg/dL puts you at relatively low risk of coronary heart disease. Even with a low risk, however, it’s still smart to eat a heart-healthy diet, get regular physical activity and avoid tobacco smoke. Have your cholesterol levels checked every five years or as your doctor recommends.

200–239 mg/dL: Borderline-High Risk
If your total cholesterol falls between 200 and 239 mg/dL, your doctor will evaluate your levels of LDL (bad) cholesterol, HDL (good) cholesterol and triglycerides. It's possible to have borderline-high total cholesterol numbers with normal levels of LDL (bad) cholesterol balanced by high HDL (good) cholesterol. Work with your doctor to create a prevention and treatment plan that's right for you. Make lifestyle changes, including eating a heart-healthy diet, getting regular physical activity and avoiding tobacco smoke. Depending on your LDL (bad) cholesterol levels and your other risk factors, you may also need medication. Ask your doctor how often you should have your cholesterol rechecked.

240 mg/dL and over: High Risk

People who have a total cholesterol level of 240 mg/dL or more typically have twice the risk of coronary heart disease as people whose cholesterol level is desirable (200 mg/dL). If your test didn’t show your LDL cholesterol, HDL cholesterol and triglycerides, your doctor should order a fasting profile. Work with your doctor to create a prevention and treatment plan that's right for you. Whether or not you need cholesterol-regulating medication, make lifestyle changes, including eating a heart-healthy diet, getting regular physical activity and avoiding tobacco smoke.

Your HDL (Good) Cholesterol Level


With HDL (good) cholesterol, higher levels are better. Low HDL cholesterol (less than 40 mg/dL for men, less than 50 mg/dL for women) puts you at higher risk for heart disease. In the average man, HDL cholesterol levels range from 40 to 50 mg/dL. In the average woman, they range from 50 to 60 mg/dL. An HDL cholesterol of 60 mg/dL or higher gives some protection against heart disease.

Smoking, being overweight and being sedentary can all result in lower HDL cholesterol. To raise your HDL level, avoid tobacco smoke, maintain a healthy weight and get at least 30–60 minutes of physical activity more days than not.

People with high blood triglycerides usually also have lower HDL cholesterol and a higher risk of heart attack and stroke. Progesterone, anabolic steroids and male sex hormones (testosterone) also lower HDL cholesterol levels. Female sex hormones raise HDL cholesterol levels.

Your LDL (Bad) Cholesterol Level

The lower your LDL cholesterol, the lower your risk of heart attack and stroke. In fact, it's a better gauge of risk than total blood cholesterol. In general, LDL levels fall into these categories:

LDL Cholesterol Levels

Less than 100 mg/dL
Optimal

100 to 129 mg/dL
Near Optimal/ Above Optimal

130 to 159 mg/dL
Borderline High

160 to 189 mg/dL
High

190 mg/dL and above
Very High

Your other risk factors for heart disease and stroke help determine what your LDL level should be, as well as the appropriate treatment for you. A healthy level for you may not be healthy for your friend or neighbor. Discuss your levels and your treatment options with your doctor to get the plan that works for you.

The Cholesterol Heart Profilers is a great starting point for learning about prevention and treatment options for your specific cholesterol levels. This free, confidential online service creates a printable report with the key information you need to fully understand your cholesterol levels, health risks and treatment options. You'll get a personalized cardiovascular disease risk profile, along with a summary of treatment options, potential side effects, success rates and a list of relevant medical journal articles and research studies, all summarized in plain English.

Your Triglyceride Level

Triglyceride is a form of fat. People with high triglycerides often have a high total cholesterol level, including high LDL (bad) cholesterol and low HDL (good) cholesterol levels.

Your triglyceride level will fall into one of these categories:
Normal: less than 150 mg/dL
Borderline-High: 150–199 mg/dL
High: 200–499 mg/dL
Very High: 500 mg/dL

Many people have high triglyceride levels due to being overweight/obese, physical inactivity, cigarette smoking, excess alcohol consumption and/or a diet very high in carbohydrates (60 percent of more of calories). High triglycerides are a lifestyle-related risk factor; however, underlying diseases or genetic disorders can be the cause.

The main therapy to reduce triglyceride levels is to change your lifestyle. This means control your weight, eat a heart-healthy diet, get regular physical activity, avoid tobacco smoke, limit alcohol to one drink per day for women or two drinks per day for men and limit beverages and foods with added sugars. Visit your healthcare provider to create an action plan that will incorporate all these lifestyle changes. Sometimes, medication is needed in addition to a healthy diet and lifestyle.

A triglyceride level of 150 mg/dL or higher is one of the risk factors of metabolic syndrome. Metabolic syndrome increases the risk for heart disease and other disorders, including diabetes.

Causes of high cholesterol level

There are several factors that may contribute to high blood cholesterol:
a diet that's high in saturated fat and, less so, high in cholesterol (see How diet affects cholesterol below)
lack of exercise may increase LDL ("bad") cholesterol and decrease HDL ("good") cholesterol
family history - people are at a higher risk of high cholesterol if they have a direct male relative aged under 55 or a female relative aged under 65 affected by heart disease
being overweight, which may increase LDL ("bad") cholesterol and decrease HDL ("good") cholesterol
age and sex - cholesterol generally rises slightly with increasing age, and men are more likely to be affected than women
drinking more than the recommended amount of alcohol (ie more than three to four units per day for men and two to three units per day for women)

Rarely, high cholesterol can be caused by a condition that runs in the family called a lipid disorder (familial hypercholesterolaemia). About one in 500 people have this condition.

Other health conditions such as poorly controlled diabetes, certain kidney and liver diseases and an underactive thyroid gland may also cause cholesterol levels to rise. Some medicines such as beta-blockers, steroids or thiazides (a type of diuretic) may also affect blood lipid levels.

How diet affects blood cholesterol

Only a small amount of cholesterol comes directly from your diet - the majority is produced by your liver. However, if your diet is high in saturated fats and cholesterol this can cause your liver to produce more LDL ("bad") cholesterol. The amount that diet influences cholesterol levels varies from person to person.

Measuring cholesterol

The amount of cholesterol in your blood is measured in units called millimoles per litre of blood, usually shortened to "mmol/litre" or "mmol/l". America uses the units milligrams per decilitre of blood: "mg/dl" instead. Current UK guidelines state that it is desirable to have a total cholesterol level under 5mmol/l, and an LDL level under 3mmol/l.

In order to estimate your risk of getting CVD, the best indicator of risk is your TC:HDL ratio. A lower ratio is desirable, because this indicates that you have high levels of HDL.

Measuring cholesterol involves a simple blood test. Usually you will be asked not to eat for 12 hours before the test so that your food is completely digested and doesn't affect the test. A blood sample may be taken either by using a needle and a syringe, or by using a finger prick. You can have this test at your GP surgery, at a hospital appointment, or as part of a health assessment examination.

Home-testing kits for cholesterol may not be very accurate. Also, cholesterol is just one of the risk factors for heart disease. It should ideally be measured under medical supervision so that other important issues, such as blood pressure, age and whether or not you smoke, are taken into account. Speak to your pharmacist about your result if you do choose a home testing kit.

Who should have a cholesterol test?

Anyone who has any cardiovascular disease, such as coronary heart disease, peripheral vascular disease (disease in the blood vessels that supply the limbs) or stroke, should have their cholesterol measured by a doctor.

Anyone, even children, with a family history of familial hypercholesterolaemia should have their cholesterol measured.

Anyone aged 35 or over should consider having their cholesterol measured if they have one or more of the following risk factors for CVD: family history of early heart disease, diabetes, high blood pressure, or if they smoke.

Diagnosis

Having a high cholesterol level does not cause symptoms. Most people find out they have high cholesterol when they have their blood cholesterol measured as part of a medical check-up. Alternatively, it may be identified after other health problems, such as heart disease, have been diagnosed.

Treatment

The main aim of lowering cholesterol is to reduce the risk of heart disease. The type of treatment depends on the overall risk of heart disease.

There are two ways to help lower high cholesterol. The first is with simple lifestyle changes including changing diet, managing weight and increasing exercise. The second is to combine lifestyle changes with cholesterol-lowering medicines.

Diet

Healthy eating can reduce cholesterol. Your diet should be low in saturated fats in particular, and low in fat overall. Biscuits, cakes, pastries, red meat, hard cheese, butter and foods containing coconut or palm oil all tend to be high in saturated fats, so cut down on these foods.

Large amounts of cholesterol are found in a few foods, including eggs, offal such as liver and kidneys, and prawns. However, if you're already eating a balanced diet, you don't need to cut down on these foods unless your GP or dietitian have advised you to.

It's also important to eat plenty of fibre, especially soluble fibre, which is thought to lower cholesterol. It's found in fruits and vegetables, beans and oats. Aim to eat at least five portions of fruit and vegetables each day. For more information see the BUPA factsheet, Healthy eating.

There is some evidence that foods containing substances called plant sterols or plant stanols, such as the brands Benecol or Flora pro.activ, in combination with a low fat diet and physical activity, can help to lower cholesterol.


Medicines

Cholesterol-lowering medicines are considered for people who already have CVD, or are at high risk of getting it because they have other risk factors.

The main group of medicines for lowering cholesterol are statins. Examples include simvastatin (Zocor) and atorvastatin (Lipitor). They work by reducing the production of cholesterol in the liver. Occasionally these drugs have side-effects such as indigestion and muscle pains. Other types of drugs to reduce cholesterol are called fibrates, nicotinic acids and cholesterol absorption inhibitors such as ezetimibe (Ezetrol) but these are generally less effective or have more side-effects. Your doctor will tell you more about these medicines.


Further information
The British Heart Foundation
08450 708 070
www.bhf.org.uk

Sources

Triglycerides and the heart. British Heart Foundation.
www.bhf.org.uk
accessed 12 October 2006
Heart disease. Food Standards Agency
www.eatwell.gov.uk
accessed 12 October 2006
Familial hypercholesterolaemia. HEART UK.
www.heartuk.org.uk
accessed 12 October 2006
Cholesterol. British Heart Foundation Health Statistics.
www.heartstats.org
Cholesterol and chronic kidney disease. National Kidney Foundation.
www.kidney.org
Law, M. Plant sterol and stanol margarines and health. British Medical Journal 2000: 861-864