Over the decades, cholesterol has been termed as bad, and high cholesterol level has been associated with heart diseases such as heart attacks, angina, and stroke. However, there has been no proof of the relation of high cholesterol with the occurrence of these diseases.
It is believed that obesity is associated with high cholesterol levels and that most of the cholesterol found in our bodies comes from what we eat. It is also thought that arterial diseases are caused by the formation of plaques associated with high cholesterol levels.
What is Cholesterol?
So, what is cholesterol? Cholesterol is a naturally occurring compound in the body that contains high amounts of carbon. Cholesterol is classified as a sterol, and most sterols are lipid-soluble with minimal or no solubility in water or aqueous solutions.
The Role of Cholesterol
Cholesterol is vital for several functions in the body. Cholesterol is the building block for the synthesis of cell membranes. It plays a role in the absorption of fat-soluble vitamins like vitamins A, D, E, and vitamin K. Cholesterol is a precursor in the synthesis of vitamin D from the sun. It is essential in the immune signalling pathway, especially pathways involving inflammation and T cell signalling pathways. Cholesterol plays a role in the synthesis of sex hormones like estrogen, testosterone, and progesterone.
Also, cholesterol is involved in the synthesis of glucocorticoid hormone. Cholesterol serves as a source of energy and body water, especially the stored fats during starvation. Cholesterol plays a role in the digestion of fats in the liver and nerve cell insulation (they are the major component of the myelin sheath). Moreover, it plays a role in the re-uptake of serotonin by the brain cells and as an antioxidant in the body.
Is cholesterol all bad?
Although numerous journals and articles claim that cholesterol is the mother of most heart-related fatalities, new research has contradicted some of the popular beliefs. There are two types of cholesterol, high-density lipo-protein (HDL) and low-density lipo-protein (LDL).
Low-density lipo-protein is termed as the bad cholesterol that is associated with most heart diseases. Low-density lipo-protein is a transport protein that facilitates the movement of fatty acids and glycerol from the digestive tract into the body’s serum and to the adipose tissue for storage.
In addition, foods that are rich in cholesterol have also been found to contain a high level of vitamin B, which is a vital source of choline used in the synthesis of acetylcholine. Acetylcholine is an important neurotransmitter found in the body that regulates most bodily functions. Vitamin B is critical for proper brain development of the fetus during pregnancy and in its early stages of life. That is why most parents give their children omega-three supplements in the early phase of childhood for improved brain development.
Contrary to its counterpart, the high-density lipo-protein is the good cholesterol. High-density lipo-protein facilitates the transport of fatty acids and glycerol to the liver for digestion and its utilisation. For an individual to have optimal cholesterol levels, the low-density lipo-protein levels needs to be lower than the high-density lipo-protein level.
Far from the popular belief that most of the cholesterol comes from diet, over two-thirds of the cholesterol found in our bodies is secreted from the liver. Another popular theory is that when one starves themselves of food, the fats stored will be used up. When the body detects a low level of glucose in the bloodstream, the first energy store to be depleted will be the glucose stores. And, most of the glucose will be converted to fats and lipids for storage in the body and future use.
Obesity is not at all times and an indicator of high levels of cholesterol. Some relatively thin individuals have high cholesterol levels.
What are the likely causes of high levels of cholesterol?
Genetics play a role where individuals from the same family may inherit a condition called hypercholesteremia. Eating foods rich in saturated and trans fats will increase the blood serum level of low-density lipo-proteins.
Life comorbidity such as diabetes will predispose an individual to high cholesterol levels due to the constant high blood sugar level. The high blood sugars are preferentially stored in the body as fats and triglycerides. All this contribute to increased cholesterol levels in the body.
Smoking damages the blood vessels. Nicotine found in tobacco smoke will cause blood vessels to be in a constant vasoconstrictive state. As a result, it will cause an accumulation of toxic substances, thus may lead to a hypertensive crisis.
Lack of exercise will lead to low levels of good cholesterol, which is the high-density lipo-protein and an increase in the serum low-density lipo-proteins levels.
What is the relationship between high cholesterol levels and heart diseases?
Although many believe that high cholesterol levels are associated with heart diseases and fatalities, there is no scientific and statistical proof to support their argument. According to a study done by the Framingham Heart Research Group to over 5000 people, high cholesterol level did not have a direct correlation with heart diseases.
Scientific proofs that exonerate high cholesterol levels to heart diseases
The results found were that over three-quarters of individuals who have previously suffered from myocardial infarction or stroke had normal levels of cholesterol. High cholesterol has never been singly identified as the sole cause of heart diseases. And, in countries whose population comprised of individuals with high cholesterol levels did not report high incidences of heart attacks or strokes.
The root causes of heart diseases could be due to inflammation, leptin resistance, insulin levels, lifestyle ailments, and stress. Stressful conditions will cause the body to produce cortisol, adrenaline, and noradrenaline, which mediate vasoconstriction of blood vessels. Constriction of blood vessels limits the supply of nutrients and oxygen to organs, mainly the heart and brain, which may trigger myocardial infarction or a stroke.
Inflammatory diseases such as rheumatic heart disease (RHD) and arthritis are risk factors that are associated with ischemic heart diseases. New research has shown that patients suffering from rheumatic heart disease and rheumatic arthritis have a 59% chance of dying from coronary heart diseases. They also have a 52% increased probability of suffering from a stroke.
Genetics also plays a role in heart-related illnesses. As per the research done by the Finnish Study, which was published in the American Journal of Clinical Nutrition, individuals that are carriers of the ApoE4 gene were predisposed to developing heart disease.
Behavioural factors such as excessive consumption of alcohol and smoking have been associated with heart diseases. Smokers inhale large amounts of nicotine throughout their lifetime. Nicotine is associated with reduced blood supply to organs due its effects which is the vasoconstriction of blood vessels. To support this argument most smokers or smoker who quit but had previously smoked a significant portion of their lives are known to suffer from hypertension.
The theory that atherosclerosis is caused by deposition of fats on the arterial walls that later form plaques which reduce the diameter of the arterial wall is just but a hypothesis. New research has found no correlation between arterial thickness and cholesterol consumption. High cholesterol level is not the issue here, but inflammation of the arterial wall is considered the root cause of atherosclerosis. This shows that other factors come into play when talking about heart diseases.
According to research conducted in Vanderbilt University Medical School and Saint Thomas Hospital Nashville Institute of Hypertension by a clinical professor and a certified cardiologist, metal poisoning with mercury or lead will lead to cardiovascular diseases. From as little as 5g/dl of blood lead serum will increase the probability of developing ischemic heart problems by 89%.
Research has established the link between cardiovascular diseases and consumption of Bisphenol A, popularly known as BPA. BPA is found in most plastics. The chance of getting heart diseases from BPA increases with the consumption of its chlorinated form. The use of Bisphenol A is making of plastics has been banned in many states.
Also, contrary to popular belief, high cholesterol levels is associated with improved life expectancy. As per the National Health Guidelines, individuals with an increased level of high-density lipo-proteins (above 60mg/dl) are less likely to suffer from heart ailments. The high-density lipo-protein is considered protective. Also, according to research, individuals with low triglycerides level and low-density lipo-protein levels have a raised mortality risk.
The use of cholesterol-lowering drugs like statins and low serum levels of cholesterol is associated with the genesis and development of certain cancers. Although statins are used in patients who have previously suffered from ischemic heart diseases or stroke, they are 5% effective in preventing the second incidence of heart attack or a stroke.
According to research conducted in January 2009 by the American Heart Journal Association, over 60% of patients admitted to hospitals due to heart diseases have low LDL levels. This shows that other contributing factors propagate the occurrence of a heart attack.
Research results presented in 1990 at the NIH conference stated that if the total serum cholesterol level were below 160mg, this would increase the likelihood of developing cancer in two folds. In addition, low serum cholesterol levels may cause an individual to develop gastrointestinal or respiratory diseases.
Low LDL levels in the blood could be an indicator of hyperthyroidism, malnutrition, poor metabolism due to liver disease, and overall compromised health. In addition, a low LDL level, especially in old age, is associated with behavioral changes and dementia.
Cholesterol Profiling for Heart-related diseases
The diagnosis of the total serum cholesterol level is not sufficient enough to give us conclusive information. It is recommended to test the low-density lipid lipo-protein levels and the high-density lipid lipo-protein. Conduct a comparison of the ratio of the two. Also, assess the levels of triglycerides in the body.
Since most ischemic heart conditions have pathogenesis of inflammation, it is advocated to test for the serum levels of C reactive protein. C reactive protein is an indicator of the presence and extent of inflammatory processes in the body.
Individuals who are at risk of developing heart diseases should, therefore:
- Exercise as exercise, increases the level of high-density lipo-proteins that are responsible for the transportation of lipids to the liver for elimination.
- They should minimise their intake of salt. Salt contains sodium, which has the potential to increase blood volume levels by acting on the kidneys. Increased blood volume will potentiate a hypertensive crisis.
- They should quit smoking due to the apparent reason that nicotine increases the chances of having an ischemic heart event like angina or myocardial infarction.
- They should minimise or, if possible, completely stop alcohol consumption.
- They should mind their diet. It is recommended that such individuals eat vegetables, nuts, fish, fruits, cereals, cheese, and whole grains. They should minimise the intake of red meat and eat white meat in moderation.
- Processed food and meat should be avoided. When cooking, use unsaturated oils for cooking. Unsaturated oils are known to reduce the levels of low-density lipo-proteins.
- It is advised for such individuals to lose the extra weight and maintain optimum body mass index.
The take-home message from this article is that contrary to the popular belief that cholesterol is harmful to your health. Not all cholesterol is unhealthy, only the low-density lipo-proteins and the triglycerides are dangerous if they occur in large concentrations in the body serum.
High level of the high-density lipo-proteins is an indicator of good cholesterol health. There are other factors to consider when one is diagnosed with cardiovascular health problems apart from cholesterol levels. Examples of such factors include metal toxicity, other inflammatory diseases, genetics, behavioural factors, among others, that may play a role in the pathogenesis of a heart condition.
It is, therefore, crucial for physicians and clinicians to carefully assess all presenting conditions before concluding that high cholesterol levels as the prime cause of heart disease.
Also, the role of cholesterol in the synthesis of the cell membrane, hormones, and vitamin D from sunlight depicts the importance of having cholesterol- containing foods in your diet.
You may also like our free nutritional eBooks, available to download.