Cholesterol is always in the news and is a common word said by many spouting nutrition and dietary knowledge, I am not going to go into much depth in all the science of what cholesterol is, its metabolism and chemical structure but we will be going into depth into what hypercholesterolemia (high cholesterol) is and all the facts you need to be and stay healthy.
As the name suggests hypercholesterolemia is the occurrence of high levels of cholesterol within the blood, making it a specific form of hyperlipoproteinemia & hyperlipidaemia (elevated blood lipoprotein and high lipid count). Cholesterol is one of three main classes of lipids and is a sterol, our cells require cholesterol to build membranes and therefore cholesterol is essential to life.
Cholesterol is transported through the body within lipoproteins in the blood plasma as it is insoluble in water. These lipoprotein are classified into different categories depending on their density:
- Very low density lipoprotein (VLDL)
- Intermediate density lipoprotein (IDL)
- Low density lipoprotein (LDL)
- High density lipoprotein (HDL)
Now all we ever really hear about is LDL and HDL but all these lipoproteins carry cholesterol, the reason we only hear about HDL and LDL is because low HDL occurrence and high LDL occurrence are associated with health damage, however high HDL lipoproteins are purported to be protective against many negative high cholesterol effects.
Signs & Symptoms of hypercholesterolemia
In technical terms high blood cholesterol has no symptoms, however it causes problems when the hypercholesterolemia is left unchecked for years. Chronic hypercholesterolemia leads to the development of atheromatous plaques within the arteries and vessels, which finally leads to a complete blockage occurring (occlusion) from an ever progressing narrowing (stenosis) within the vessel. Small plaques on occasion break away and cause clots to form which may completely block the flow of blood. If one of the vital coronary arteries becomes blocked then a heart attack (myocardial infarction) will occur, not to be confused with cardiac arrest. A stroke will occur if the blockage occurs to an artery supplying the brain, causing an ischemic stroke. If temporary ischemia occurs to the brain it is known as a transient ischemic attack (TIA) which manifests itself as:
Loss of vision (temporary)
Numbness in limbs (usually one sided)
Tingling (usually one sided)
Loos of equilibrium
As with the brain, symptoms when blood is blocked from entering the chest and tissues also cause symptoms:
Chest Pain (deficient blood to heart)
Visual loss in one eye (ischemia of the eye)
Calf Pain and muscle tightness (deficient blood supply to legs)
Abdominal Pain after eating (deficient blood supply to intestines)
Although generally asymptomatic high cholesterol does lead to some clinical findings, xanthelasma palpebrarum is one example of this, this is when there is yellow/white like plaques under the skin which may appear similar to healed scars. Another example would be xanthomata of the tendons where cholesterol rich plaques cover the tendons, usually of the ankle and fingers. A grey staining of the peripheral cornea can occur due to high cholesterol and this is known as acus senilis.
Causes of High Cholesterol
High cholesterol has a magnitude of differing causes, however it is mainly a combination of many factors:
Lack of exercise
Diabetes mellitus type 2
Possibly the single most important factor in the development of high cholesterol, diet plays an integral role. However the role diet plays between each individual varies greatly, some individuals have an uptake of up to 60% non-esterified cholesterol within the intestines whilst other individuals will only have a 20% uptake, plant sterols and dietary fibre have a direct affect upon uptake.
Reducing fat intake, specifically saturated fat reduces serum cholesterol, with dietary sucrose and fructose increasing LDL (Bad Cholesterol) serum concentration. It is recommended that those who have hereditary hypercholesterolemia restrict their total fat intake to 20-30% of overall energy intake with only 4-6% of that made up through saturated fats, cholesterol intake for those with hereditary hypercholesterolemia should be between 100-200mg per day. A good change for everyone to make should be the inclusion of 10-20g of soluble fibre intake per day as this has been proven to decrease serum cholesterol. Changing ones diet can lead to a 15% decrease in serum levels of cholesterol. It also leads to a more healthy fat percentage, it has shown that a loss of 1kg in obese individuals will lead to a drop of 0.8mg/dL of LDL cholesterol.
In certain circumstances genetic factors can be accountable for an individual’s high cholesterol, genetic mutations to the autosomal dominant APOB gene, HCHOLA3, autosomal recessive LDLRAP1 gene and the LDL receptor gene.
However this is uncommon and does not account for the major increase in high cholesterol within the UK.
Ranges, Diagnosis & Ordering
|Reading of Cholesterol levels|
|Total cholesterol||under 200||under 5.2||desirable|
|over 240||over 6.2||high|
|LDL cholesterol||under 100||under 2.6||most desirable|
|160-189||4.1-4.9||high and undesirable|
|over 190||over 4.9||very high|
|HDL cholesterol||under 40||under 1.0||undesirable; risk increased|
|41-59||1.0-1.5||okay, but not optimal|
|over 60||over 1.55||good; risk lowered|
|Signals to decrease LDL cholesterol|
|coronary risk is:||Reason:*||Individual should take action lowering LDL if the level is over:||LDL reduction is indicated if the level is over:|
|high||Have many or one extreme risk factor e.g. coronary heart disease (CHD), diabetes, peripheral-artery disease, carotid-artery disease or aortic aneurysm (AA).||70 mg/dL, 3.88 mmol/dL especially if there are risk factors||100 mg/dL, 5.55 mmol/dL|
|moderately high||a 10-20% risk of heart attack in 10 years and two or more risk factors||100 mg/dL, 5.55 mmol/dL||130 mg/dL, 7.21 mmol/dL|
|moderate||less than 10% risk of heart attack in 10 years and two or more risk factors||130 mg/dL, 7.21 mmol/dL||160 mg/dL, 8.88 mmol/dL|
|low||No risk factors or only one||160 mg/dL, 8.88 mmol/dL||190 mg/dL, 10.5 mmol/dL|
*Risk Factors: Obesity, Angina, CHD, COPD, AA, PAD, diabetes, Hypertension, Anxiety/Stress etc.
Cholesterol is measured in mmol/L in the UK and Europe but md/dL in the states. The NHS states that 5 mmol/L or less of total cholesterol is good along with 3 mmol/L or less of LDL, this is decreased by 1mmol/L on both for those at high risk of cardiovascular disease, so 4 mmol/L or less for total cholesterol and 2 mmol/L or less for LDL. Whilst these are just indicators of what the norm should be they need to be interpreted correctly with risk factors and other lifestyle factors. The occurrence of CHD increase in correlation with elevated total serum cholesterol, with the usage of LDL and low HDL figures being used to predict future CHD in individuals. Higher levels of smaller denser LDL are purported to carry a higher risk with HDL increases decreasing risk. Hypercholesterolemia in the past was classed using lipoprotein electrophoreses and the Fredrickson classification, however other methods have come to light and offer a larger idea in understanding the connection between atherosclerosis progression and clinical problems.
There are many different methods to help people who suffer from high cholesterol:
Limit alcohol consumption
Avoiding Trans fat
Avoiding saturated fats
Adding 30 minutes of moderate activity a day
Decreasing body fat %
Statins are the most commonly used medications to treat high cholesterol if lifestyle changes are deemed to be ineffective. Other medications used are nicotinic acid, fibrates and cholestyramine, which are used when it is found that statins are not easy tolerated by the individual, statins are generally very effective and reduce total cholesterol by up to 50% in the majority of individuals, and this seems to be across the board with all statins in circulation. However there is debate whether statins are useful in persons who do not have cardiovascular disease. If children suffer from hypercholesterolemia then statins are not advised, lifestyle changes are advised.
A review of phytosterols and phytostanols showed an average 9% lowering of LDL within individuals with in the USA. Many experts believe that without long term data stenols/stanols are not a replacement for a lifestyle change or statins at treating cholesterol.
Garlic has been shown in some studies to decrease total cholesterol in the blood, however its effectiveness is varied to individual. Garlic can thin the blood and decrease clotting and those who are going into surgery should refrain from garlic supplementation.
Coming from sugar cane, policosanol has been shown to be effective in decreasing LDL, most supplements are found over the internet and within the U.S. it is paramount that those wanting to supplement policosanol only go for policosanol that is extracted from sugar cane and not beeswax.
Soluble fibre found within oat bran, seeds, flax, lentils and beans are all great at reducing LDL and total cholesterol within the body.
Omega-3 fatty acids
Consuming omega-3 helps reduce total serum cholesterol, omega-3 helps decrease the rate at which the liver produces triglycerides and LDL cholesterol, it can have an anti-inflammatory effect which decrease the plaques that occur within the arteries. Omega-3 like garlic can cause a blood thinning effect and again supplementation should be avoided in those about to go into surgery.
Just to make us aware of how bad the problem is getting within the UK, our average total cholesterol is 6.1% whilst in Japan & China it is 4%, this correlates directly with high rates of CHD within the UK and lower rates within China and Japan.
By. Chris Collins