Cholesterol, which is also known as a lipid, is a fatty substance found in your blood that is very important to every cell in your body. Cholesterol is essential for cell structure because it forms part of each cell’s membrane, helping it keep its shape. Even the cell’s organelles (little organs) have cholesterol in their tiny membranes, helping them function properly.
Cholesterol is mainly made by the liver, but as we all know, is also delivered through our diets. Cholesterol is carried by proteins in the blood to all the cells in the body. When the cholesterol and protein combine, they are called lipoproteins. There are harmful and helpful lipoproteins known as LDL and HDL, or ‘bad’ and ‘good’ cholesterol.
Low-density lipoprotein (LDL), or ‘bad cholesterol’, carries cholesterol from your liver to the cells that need it. But if there is excess cholesterol in the blood that the cells don’t need, it stays in the arteries. This fatty material can then build up in the arteries leading to heart problems.
High-density lipoprotein (HDL), or ‘good cholesterol’, delivers the cholesterol to the cells, then carries the excess cholesterol back to the liver, where it is either broken down or passed out of the body as a waste product.
So the key is to have the right type of cholesterol in our bodies, as well as the right amount. High cholesterol can be a result of eating a diet that is high in saturated fat, a history of smoking, lack of exercise, a high intake of alcohol as well as diseases of the liver and kidney.
You can reduce your cholesterol level by replacing saturated fats and trans-fatty acids (mostly from animal products such as red meat and dairy, as well as processed foods) with the healthy monounsaturated and polyunsaturated fats (mostly from plants and oily fish). Choose foods that are high in fibre such as beans and lentils, fruits and vegetables, and seeds and nuts. Regular physical activity can also increase your levels of “good” (HDL) cholesterol.