Disturbances of fat (lipid) transport, processing and production lead to elevated levels of fat in the blood. When levels are higher than normal, this is known as hyperlipidemia. Symptoms are often not present for a long time. Hyperlipidemia is therefore often first recognized when long-term effects arise (such as a heart attack or stroke). The cause can be due to genetics, improper nutrition, an unhealthy lifestyle or associated underlying diseases. In the industrial western world, hyperlipidemia is among the highest risk factors for cardiovascular disease. According to recent studies, 55 to 60 percent of adults have an elevated blood fat level—this is divided between Triglycerides and Cholesterol.
Cholesterol is not inherently bad. It is necessary for the development and functioning of our body’s cells, and forms the framework for hormones, bile acids and Vitamin D. The cholesterol level must be assessed individually for each person, as not every elevation must be treated with medications; a change to a healthy lifestyle is often enough. However, in combination with risk factors such as smoking, Diabetes, High Blood Pressure and Heart Disease, medical treatment is often unavoidable.Cholesterol has various functions:
- Essential part of cell membranes
- Jointly responsible for cell tension, permeability and repair
- Production of bile acids
- Production of many hormones and Vitamin D
If the body receives more than the recommended quantity of 300 milligrams per day of cholesterol through food, the production from the body itself decreases.
Cholesterol is a fat-like substance. Much cholesterol is actually produced within the body, with the largest source being the liver. 90 percent of cholesterol released from the liver into the bloodstream arrives at various body cells in the form of a fat-protein compound (cholesterol + protein = lipoprotein), where they are absorbed.
Lipoproteins are classified according to their density:
- HDL (High Density Lipoprotein)
- LDL (Low Density Lipoprotein)
The higher the lipid portion in the compound is, the lower its density, and therefore the more dangerous for the health it is.
HDL is a small lipoprotein that is formed in the intestine and liver, and serves as a means of transport for fat-like substances. Excess cholesterol is removed from the circulation by binding to HDL. HDL then carries cholesterol to the liver where it is converted into bile, and then eliminated. It therefore reduces the risk of Arteriosclerosis and Heart Attack. However, it is not the amount of HDL that is important, but its function. While there is currently no clinically proven treatments solely treating low HDL, reducing your weight, regular physical activity and healthy eating can positively affect your HDL level. A normal value is greater than 40 mg/dl for men and greater than 45 mg/dl for women.
Lipoproteins are composed of fat and protein, which bind fat-like substances (i.e. cholesterol) and transport them throughout the bloodstream. Lipoproteins that have a lower density than HDL are called “low density.” LDL transports excess cholesterol from the liver throughout the body. If the concentration of LDL-cholesterol in the body is high and the inner lining of blood vessels is damaged, the lipid particles can attach to the inside of the blood vessel. It is there oxidized and attracts white blood cells (macrophages), leading to inflammation of the vessel wall and atherosclerotic plaque formation. Previously damaged blood vessels (such as from high blood pressure or smoking) are particularly at risk. Circulation problems stem from these depositions, such as in the leg or brain. If a plaque is torn, platelets are attracted to the site, which can block the blood vessel. If a coronary vessel is affected, for example, this can lead to a heart attack.
All forms of cholesterol have certain responsibilities. The amount of cholesterol present should therefore be neither too high, nor too low. In order to determine how much cholesterol is present in the body, a cholesterol level measuring HDL and LDL levels is checked. The concentration of cholesterol in the blood is reported in either mg/dl (milligrams per deciliter) or mmol/dl (millimoles per deciliter).Normal cholesterol levels:
Total cholesterol level:
- Normal < 200 mg/dl
- Borderline < 240 mg/dl
- Normal > 45 mg/dl
- Borderline < 45 mg/dl
- Normal < 130 mg/dl
- Borderline < 160 mg/dl
- Low risk: 0-1 risk factors present. The maximum LDL should be < 160 mg/dl
- Moderate risk: 2+ risk factors. The maximum LDL should be < 130 mg/dl.
- High risk: presence of risk factors such as Heart Attack or Diabetes Mellitus. The maximum LDL should be < 100 mg/dl.
An elevated cholesterol level can be due to an inherited genetic defect. In this case, receptors on the cells are missing, which are normally responsible for binding cholesterol, making cholesterol uptake into the cell possible. Therefore, the cholesterol level remains persistently elevated. High cholesterol is, however, most often due to an unhealthy lifestyle including lack of physical activity, obesity, poor nutrition or smoking.
Other diseases such as Hypothyroidism, reduced kidney function or liver disease can also lead to an elevated cholesterol level.
In addition, medications taken regularly (such as those taken for chronic diseases) can have a negative impact on the cholesterol level.
Too much stress over an extended period of time can also contribute to elevated cholesterol. When stressed, the body releases hormones (Adrenaline and Cortisol), which in turn cause the release of free fatty acids and triglycerides, causing an elevation in cholesterol. An additional possibility is that, in stressful situations, the body cannot remove enough Cholesterol and an inflammatory process stimulates cholesterol release.
An elevated cholesterol level can strongly affect ones health. It is therefore important to monitor your cholesterol level in order to prevent vascular calcifications and cardiovascular disease. Proper nutrition can help steer your cholesterol level in the right direction, and can even often bring it back under control.Read more on our Heart Tips page.