Cholesterol is something we’ve all heard about. It’s been given enormous publicity over the past few years. Too much is bad for us…. can cause our arteries to ‘fur-up’….. leading to heart disease.
All true … but that’s not quite the full picture…. and it’s not all bad news!
Cholesterol, is in fact, essential to our health and wellbeing. Without it, our bodies couldn’t function, we couldn’t even stay alive! Cholesterol is a necessary component of every cell in our body. It’s found in large amounts in brain and nerve tissue, it’s a building block for various hormones, including our sex hormones, testosterone, oestrogen and progesterone – and it’s used to make bile acids, which are a vital part of digestion. So, cholesterol is not all bad news. But, the problems come when we have to much of it floating around our bloodstream. Then, it really does become a major problem to the health of our hearts by ‘clogging up’ our arteries.
So, exactly what is cholesterol?
Cholesterol is a fatty substance that the body can either make in the liver, or we can take in from the food that we eat. Cholesterol and other fatty substances, such as triglycerides (fatty molecules formed in the liver from the fat you eat or from other internal sources), are insoluble in water. To imagine what this means, think of trying to clean a greasy pan without using washing-up liquid – the fat just congeals and floats to the surface. The body couldn’t possibly cope with clumps of fat floating around, so cholesterol and triglycerides are dissolved within particles called lipoproteins, then carried to your tissues in the bloodstream. This is a very efficient system of getting these essential fatty substances to all the body cells that need it.
There are three major type of lipoprotein:
Very Low Density Lipoprotein (VLDL).
VLDLs transport mainly triglycerides from your liver to your body tissues. If you eat lot of saturated fats, then you are likely to have lots of VLDLs floating around in your bloodstream. High triglycerides levels are known to be an important risk factor in heart disease.
Low Density Lipoprotein (LDL).
LDLs are the mainly transporter of cholesterol to your tissues. If your diet is high in cholesterol, your liver will manufacture more LDLs to handle it – and your LDLs will be high. So, LDLs are often termed “the baddies” – and high LDLs levels are a major risk factor in heart disease.
High Density Lipoprotein (HDL).
HDLs are the ‘garbage collectors’, picking up unused cholesterol in the blood, transporting it back to the liver for dismantling and converting into bile acids to help our digestive processes. Some of the cholesterol is then passed out in stools, thus providing us a major route for the excretion of unwanted cholesterol. This is why HDLs are often termed “the goodies”! A high level of HDLs is now thought to be very important for heart health.
When you have your cholesterol checked, you are normally given a single value, say between 4 and 6 (the units are in millimoles per litre of blood – mMol/L) and likely informed that an ideal value is around 5.2mm/l. This is a measure of your Total Cholesterol (TC). Basically, this is the total of your LDLs and HDLs. However, what this doesn’t tell you is how much of this total is ‘bad’ LDL and how much is ‘good’ HDL. Current research now tells us that whilst high TC levels are not good for cardiovascular health, perhaps more importantly may be the need for high HDLs as a key preventor of heart disease. Many doctors are now consider the ratio of LDL/HDL or TC/HDL as better predictors of heart disease risk, than TC on its own.
Additionally, a low level of triglycerides (TGs) is also highly desirable for coronary prevention.
Most certainly, diet can certainly help control your blood lipids (fats) and that’s one good reason why low fat, high fibre eating plans are now routinely recommended. But exercise also has a very important part to play in controlling both cholesterol and triglycerides.
Exercise will help raise your HDL profile…..
Many studies have now shown that regular aerobic exercise will considerably elevate your HDLs. In fact, most researchers consider exercise as a more powerful factor than diet in raising HDLs. Our own recent studies at University College Chester noted a 35% in HDLs with a group of sedentary ladies who undertook an 8-week course of moderately vigorous low impact aerobics. Women tend to have a naturally higher HDL level than men, so the potential for improving HDLs amongst males is significant. This is now thought to be one of the most significant reasons for the dramatic drop in coronary risk for active males.
Exercise will help lower your triglycerides…..
Significant changes in TGs have been shown by many researchers. One recent North American study reported a fall of 43% in TGs amongst a group of sedentary men and women who were asked to engage in aerobic exercise, such as brisk walking, for around 30 minutes, 3-4 times a week. Your body uses the TGs as a fuel for aerobic exercise – so exercise is a great way to lower your triglycerides.
Total Cholesterol and LDLs are also shown to be lower in active people, largely due to the generally healthier lifestyle, such as good eating habits, not smoking and moderate alcohol consumption.
Controlling blood fat levels is a key feature in improving the health of your heart.
A combination of low fat, high fibre healthy eating habits and taking regular aerobic physical activity are powerful ways of exercising this cholesterol control.
So, keep your blood profile healthy – eat sensibly and exercise regularly.