What is cholesterol? Can it ever be good for you? How high or low should your cholesterol be? And is there anything you can do about it?
Here is a guide for cholesterol, both good and bad.
What is cholesterol?
Cholesterol is a waxy, fat-like substance that is naturally present in all parts of the body. It’s mainly manufactured in the liver, with a small amount coming from food. Your body needs some cholesterol to work properly in many regards, but if you have too much in your blood (especially of the “bad” LDL type), it can stick to the walls of your arteries and cause plaque. Eventually, plaque can contribute to narrowing of your arteries or even block them.
Therefore, high levels of cholesterol in the blood can increase your risk of heart disease. Your cholesterol levels tend to rise as you get older and you are likely to have high cholesterol if members of your family have it, if you are overweight, or if you eat a lot of fatty foods.
Good and Bad Cholesterol
“Good cholesterol”, High-Density Lipoprotein (HDL), takes cholesterol away from your arteries to the liver to be eliminated. This means that a high level of good (HDL) cholesterol is thought to be heart healthy.
“Bad cholesterol”, Low-Density Lipoprotein (LDL) takes cholesterol from your liver to the body tissues. If there’s a high level of bad (LDL) cholesterol in the blood, it can build up in the walls of your blood vessels, causing them to narrow and increasing your risk of coronary heart disease.
To help keep your heart healthy it’s important that your bad (LDL) cholesterol remains low and your good (HDL) cholesterol stays high.
How is cholesterol measured?
Cholesterol is measured in units called millimoles per litre of blood, usually shortened to mmol/litre or mmol/l. In the US, it is measured as milligrams per decilitre of blood, or mg/dL.
What level should your cholesterol be?
According to the Heart and Stroke Foundation of Canada, when deciding your target cholesterol ranges, your doctor will take into account your cardiovascular risk factors such as age, sex, blood pressure, and whether you have diabetes or smoke. Generally, good target levels are:
- A total cholesterol less than 5.2 mmol/L (200 mg/dL)
- An LDL-cholesterol less than 3.5 mmol/L (about 130 mg/dL)
- An HDL-cholesterol higher than 1.0 mmol/L for men and 1.2 mmol/L for women (about 40 mg/dL)
- A total cholesterol/HDL-cholesterol ratio less than 5.0
What causes raised cholesterol levels?
There are a number of factors that can contribute to a raised cholesterol level, however a common cause is eating too much fat and, in particular, too much saturated fats, trans fats, and cholesterol itself. High intake of saturated fat and trans fat may raise bad (LDL) cholesterol levels.
Other factors, such as a family history of raised cholesterol, getting older, not getting enough exercise, being overweight, an under active thyroid gland, diabetes or kidney problems can all have negative effects on your blood cholesterol levels.
What should you do if you’re worried about your cholesterol?
If you have any concerns about your cholesterol or any aspect of your heart health you should consult your healthcare practitioner and have your cholesterol levels checked.
If any of your cholesterol levels are outside the “right” target level for you, your doctor will discuss lifestyle changes and may prescribe nutritional supplements or medication to keep your levels in balance.