Cholesterol, which has a number of important roles in the body, is produced by your liver mainly from dietary fat. Cholesterol is transported around the body in the form of lipoproteins.
The main types of lipoproteins are:
- High density lipoproteins (HDL)
- Low density lipoproteins (LDL)
- Very low density lipoproteins (VLDL)
LDL and VLDL are ‘bad’ cholesterol. High levels of LDL or VLDL in the blood for prolonged periods tend to deposit cholesterol on the inside of your arteries, eventually constricting them to the point where the flow of blood through these blood vessels is restricted. HDL, on the other hand is ‘good’ cholesterol. This tends to mop up cholesterol deposits in your arteries, carrying them to the liver where they are removed from the body. In this way, HDL can help to restore the flow of blood through your arteries.
No doubt you’re aware that eating too much saturated fat will inevitably lead to a piling on of the pounds. But are you aware of what else these fats are doing to you?
How too much saturated fat can clog up your arteries?
When you eat saturated fat, your liver converts the fat to cholesterol. Too much fat in your diet will lead to high cholesterol levels in your blood, which in turn leads to a build-up of fatty deposits in your arteries. In the same way that too many large slow-moving vehicles cause a motorway to become blocked and halt traffic flow, too much fat causes the arteries to become clogged and halts blood flow. This blocking of the arteries is known as atherosclerosis, and it can impede – and in some cases prevent altogether – blood flow, stopping the blood’s cargo of oxygen and nutrients from reaching the parts of your body where they’re needed.
What happens next depends on which arteries become blocked.
If the arteries supplying the heart are blocked, you’ll experience chest pains. This is called angina. If left untreated, the symptoms will worsen, and you could suffer a heart attack. If the arteries in your legs become blocked, you’ll experience pain when you walk, and your mobility will become more restricted.
We’re constantly being warned of the perils of having too much cholesterol in our blood. It can raise blood pressure, put us at higher risk of heart attacks, stroke and diabetes. But how many of us realise that it’s the fat, not the cholesterol that we eat that pushes up our blood cholesterol levels. What’s more, how many of us realise that some types of cholesterol are actually good for you?
Good and bad cholesterol
Cholesterol is a fatty substance that your liver produces from the fat that you eat. Cholesterol is essential for the walls of your body’s cells to function properly, and for the production of some very important chemicals in the body. There are two major types of cholesterol your body produces:
Know your numbers
An optimal cholesterol level is currently below 5mmol. If you don’t know your cholesterol it may be worth finding it out. Your GP or pharmacist may be able to help.
Cutting out the bad stuff
Just as there is good and bad cholesterol, there is also good and bad fat in the food that we eat. Good fat in your diet is converted to good cholesterol, while bad fat is converted to bad cholesterol.
- Bad fat – Bad fat is saturated fat. This is found in Full fat dairy products, Fatty cuts of meat and meat products – sausages, beef burgers, pies, Butter and full fat spreads, Cakes, biscuits, crisps, nuts – ‘hidden’ fats
- Good fat – Good fat is polyunsaturated fat and monounsaturated fat. Polyunsaturated fat is found in seed oils, oily fish (mackerel, herring, pilchard, sardine, trout and salmon). Monounsaturated fat is found in avocado, olive oil
So overall, less of the biscuits, chips, cream and butter. Replace these with sunflower oil, olive oil and polyunsaturated spreads, and more of the oily fish.