Cholesterol: The Good, The Bad and The Ugly.

Cholesterol: The Good, The Bad and The Ugly

Cholesterol is a compound found in most body tissues. It is an essential substance due to its role in the cell membrane, bile acids and the production of vitamin D and hormones. Cholesterol can't dissolve in your blood which means it is transported in your bloodstream by carrier proteins, called lipoproteins. There are two types of lipoproteins that carry cholesterol: High-density lipoproteins (HDL) and Low-density lipoproteins (LDL). 

Cholesterol is vital. It is essential to every cell in the body and thus involved in the reproductive system, brain activity, movement of muscles, structure of bones and subsequently without cholesterol we would cease to exist. This is why our bodies make it, the chemical formula is C27H46O. There is no good or bad version of this formula. Due to cholesterols non-polar hydrocarbon tail, it is not water soluble- which is why it can not be transported by the blood but is carried by lipoproteins. 

You are all no doubt aware of the popular hypothesis on the relationship between cholesterol and heart disease. Lipoproteins which carry cholesterol- like mentioned earlier- are categorised: LDLs carry cholesterol from the liver to other cells, where it is needed; HDLs carry 'recycled' or excess cholesterol back to the liver to be transported out the body. Both have important purposes, yet they have been separated into "Good" and "Bad" . In the words of good and bad, LDL is the bad one as it collects in the walls of blood vessels, causing the blockages of arteriosclerosis. However, none of this is true. In the Framingham Heart Study, it was shown that intake of cholesterol has no correlation with heart disease. In figure 1 you can see that men and women with above average cholesterol levels had nearly identical rates of heart disease as people with average cholesterol levels. 

Fig. 1

The man responsible for the "diet-heart hypothesis", Ancel Keys, based the ideas on early experiments with chickens and rabbits. However, due to chickens and rabbits being vegetarian, their physiology is not adapted to handling large amounts of cholesterol. But, we can not apply this information to humans (omnivores with significant differences in physiology). After a life time of research he realised this:

“Cholesterol in food has no impact on cholesterol in the blood and we’ve known that all along.” Ancel Keys.

Though it is still accepted as gospel truth by the general public and many medical professionals, most researchers and the scientific community now believe the primary causes of heart disease are inflammation and stress. If cholesterol did cause heart disease, all genders, races and ages would be affected as it is a natural substance in all people. However, this is not true. A recent study at the  Conference on Low Blood Cholesterol, showed women are 300% less likely to suffer from heart disease than men, despite having higher average cholesterol levels. Heart disease and most other terminal illnesses are brought about by ageing, life style choices and extreme dietary factors.

Cholesterol is commonly associated with high sugar diets. However, the logic behind this has been reversed. The disadvantages with a diet full of carbohydrates is not the fact it increases cholesterol but the fact sugar is later stored as fat, which can have long term complications. Do not think of cholesterol as something you should avoid from your food, as your liver produces it constantly. If you consume extra cholesterol, from food like eggs and meat, your body will only absorb it if it is needed. The cells lining the small intestine contain transporter molecules that absorb cholesterol. However, if your body does not require any more, there is another molecule that pumps the cholesterol back into the intestine to be eliminated. 

The reason sugar is linked with cholesterol is due to LDL being oxidised and carbohydrates causing oxidation. When LDLs are oxidised they can become small and dense which can be linked with heart disease. Additionally, when our diets include too much carbohydrates, blood insulin levels spike. As a result the bodies cells are told to produce more cholesterol. The build up in blood vessels, which cause heart disease, are not due to the intake of excess cholesterol but the affect sugar has on cholesterol and other substances in our body. So high cholesterol levels are usually achieved due to high 'carb' diets, not from foods that are high in fat and cholesterol. Therefore, by avoiding excess carbohydrates, we can avoid cardiac complications. 

Statins are drugs used to inhibit the production of cholesterol, in attempt to treat heart disease. They work due to having an anti-inflammatory affect, the fact they stop the body from producing a vital substance is an unfortunate side affect. If we reduce cholesterol, we are slowing all the vital processes in the body. One in 500 people have cholesterol levels which are too high, and this drug could be helpful for them. But, the majority of people are inhibiting the production of a substance involved in all life processes. 

Cardiology researchers are now turning away from the notion that saturated fat and cholesterol cause heart disease. After all, how could substances that we have been eating for thousands of years cause heart disease, which is a relatively new phenomenon? Cardiologists are finding instead that refined carbohydrates, which we have only been eating in significant quantities for about 100 years, are the most important dietary factor at the root of heart disease.  


So there you have it. Contrary to popular belief, cholesterol is not a dangerous poison that causes heart disease. Rather, it is an essential nutrient present in the cell membranes of all tissues of all mammals, and has some very important functions in the body. In fact, in many studies, low cholesterol has been associated with a reduced life span. 

The body makes cholesterol, there are a lot of things we need to worry about, but our body trying to kill us is not one of them!