Cholesterol is a type of lipid molecule1 produced by all animal cells since it is an essential structural component of all animal cell membranes, essential to both maintaining membrane’s structural integrity and its fluidity2. However, when the levels of cholesterol in the blood are elevated above the usual levels, the condition is called hypercholesterolemia, or commonly high cholesterol. So, it is important to clarify that cholesterol, in itself, is not bad or harmful in any way – on the contrary, cholesterol is an integral compound of animal and human physiology, and the problems occur only once the levels of cholesterol reach a certain threshold.

The levels of cholesterol in the body primarily depend on its production in the liver and the specifics of the diet. Once developed, high cholesterol can lead to numerous illnesses and conditions including arteriosclerosis and different cardiovascular diseases.

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Good and bad cholesterol

Most of us are familiar with the terms “good” and “bad” cholesterol, but the meanings of those terms might require an additional clarification. Good cholesterol is related to high-density lipoprotein (HDL) while bad cholesterol denotes low-density lipoprotein. The good cholesterol or HDL reduces the risk of atherosclerosis and is beneficial to the body while, on the other hand, high LDL contributes to the risk of this condition as well as to various other cardiovascular diseases. However, LDL is also beneficial in the normal amount since it helps to transport fat molecules to the cells in the body that require it for their functioning. But once the levels exceed the normal range, LDL builds up in the arteries.

On the other hand, HDL’s primary function within the body is to bring fat molecules away from the cells and back to the liver where they get broken down or excreted as waste. This means that HDL plays a crucial role in preserving the balanced levels of cholesterol and fat in the body. It is also worth mentioning that in women, levels of HDL are naturally somewhat higher than in men.

The high cholesterol or hypercholesterolemia is present once there is too much of LDL or bad cholesterol in the body, relative to HDL, leading to the accumulation in the blood vessels. This further emphasizes that cholesterol is never the problem in itself, but actually the ratio between the two types of cholesterol.

What are normal cholesterol levels?

When you measure your cholesterol, the test focuses on the total level of cholesterol in the blood. The different amounts of total cholesterol can provide valuable insight into your health and potential for developing hypercholesterolemia. Some approximations can be given in through the ratio between cholesterol measured in millimoles and blood measured in litres:

  • < 0.5 millimoles per litre is an ideal level
  • 5-6 millimoles per liter is slightly elevated cholesterol
  • 1-7 millimoles per liter is indicative of moderately elevated levels
  • 1+ millimoles per liter means high cholesterol

What causes elevated cholesterol

There can be many reasons why an individual has elevated cholesterol, with genetics and hereditary dispositions playing an important role. With extremely high levels of cholesterol, this is usually the root cause. This is why it’s important to know if someone in your family has high cholesterol since you might also be susceptible to this condition.

Some other causes include:

  • Kidney disease
  • Slow metabolism
  • Diabetes
  • Alcohol abuse
  • Unhealthy diet rich in saturated fats
  • High blood pressure
  • Thyroid problems
  • Liver disease
  • Obesity
  • Lack of physical activity

Related health risks

High cholesterol is known to cause many other health conditions and illnesses, mostly those related to the cardiovascular system. Most notably, high cholesterol leads to arteriosclerosis, a condition in which blood vessels get tighter so blood cannot flow as easily as in healthy organism. At high values, blood vessels can partially or fully closed, preventing oxygen from reaching vital organs with potentially lethal consequences. It also increases the risk of developing chronic heart disease and blood clots.

I have high cholesterol – What can I do?

Good news is that there are many ways to bring your cholesterol ratios to normal, both through medication and lifestyle changes. For many, the first choice is to avoid food rich in natural cholesterol such as egg yolks, prawns, red meat or cheese. However, the studies have shown that it is significantly more beneficial to pay attention, not to the cholesterol, but fat one consumes through diet.

So, in order to successfully bring your cholesterol levels to the usual values, you should pay attention to the amount and types of fat consumed:

  • Replace saturated fat with single or polyunsaturated fat sources
  • Eat lean meat and dairy products
  • Eat dietary fibre (fruits and vegetables)
  • Consume cholesterol-rich foods moderately
  • Avoid fast food

High cholesterol treatment

While not dangerous in itself, cholesterol can lead to a number of complications and health issues in the long term which is why it is highly recommended to get proper treatment if you have been diagnosed with hypercholesterolemia. It is always the best to consult with your doctor in detail since for most cases lifestyle changes should be enough to do the trick.

However, if the genetics are the root cause of your cholesterol problems, then medical treatment is usually required. What’s more, if you have been diagnosed with some of the conditions which are linked with high cholesterol (such as diabetes or arteriosclerosis), medical treatment is absolutely necessary in order to prevent severe and potentially lethal complications.

Currently, there are many drugs on the market that can help you bring your cholesterol in order. While all of them rely on a mechanism of action that helps balance the relationship between the good and bad cholesterol, HDL and LDL, some of them achieve that goal by raising the levels of good cholesterol or reducing the levels of bad. Some of the most well-known and best-sold high cholesterol medicines include Crestor, Atorvastatin, Simvastatin and Fluvastatin.


  1. Cholesterol – US National Library of Medicine
  2. Steroidogenic enzymes – The Journal of Steroid Biochemistry and Molecular Biology