Physical inactivity and a diet rich in saturated fats can lead to high cholesterol. The Department of Dietetics at Singapore General Hospital explains the functions and types of cholesterol in the blood.
What is cholesterol?
Cholesterol is a waxy, fat-like substance that is found in all cells and tissues in our body. It is essential in maintaining normal body function by making useful hormones, vitamin D, bile acids that are used in the digestive process, etc.
Causes of unhealthy cholesterol levels
Various factors can cause unhealthy cholesterol levels:
- Age and gender
- Diet – saturated fats, trans fats, cholesterol
- Overweight / Obesity
- Physical inactivity
Where does the cholesterol come from?
Our liver produces most of the cholesterol found in our body; the rest of the cholesterol is contributed by the foods we eat. Dietary cholesterol comes only from foods of animal origin, such as the liver and other organ meats; egg yolks (but not the whites, which have no cholesterol); some types of seafood such as fish roe, squid and prawns; and whole milk dairy products, including butter, cream, and cheese.
Are there different types of cholesterol in the blood? How can they affect me?
Cholesterol circulates in the bloodstream in the form of lipoproteins, which is a combination of cholesterol and protein. There are two main kinds of lipoproteins:
Low density lipoprotein-cholesterol (LDL-C)
Commonly known as “bad” cholesterol because it carries cholesterol to tissues, including the arteries.
High density lipoprotein-cholesterol (HDL-C)
Which is called the “good” cholesterol because it takes cholesterol from tissues to the liver, hence removing it from the body.
If there is excess cholesterol in the blood, some of them can build up in walls of blood vessels. Over time, this accumulates as ‘plaque’, which can make vessels narrower and less flexible. This condition is called atherosclerosis or “stiffening of the arteries”. This can happen to any blood vessels in our body, such as those of the heart i.e. the coronary arteries. When the coronary arteries are affected by atherosclerosis, it results in coronary heart disease or coronary artery disease.
Are there any symptoms associated with high blood cholesterol?
There are no obvious symptoms associated with a high blood cholesterol level. You can go for a routine blood test to determine your body’s cholesterol level.
Read on to learn about
trans fats, plant sterols and how to lower your cholesterol levels.