Despite its important transporter function, in popular science LDL cholesterol is known as the “bad cholesterol”, since on its way from the liver to the organs, it can “stick” to the blood vessel walls and cause vascular calcification (arteriosclerotic plaques). Many of these plaques mainly consist of cholesterol deposits.
On the other hand, HDL cholesterol is often referred to as “good” cholesterol”, since on its way from the organs to the liver, it acts as a “garbage collector”, protecting the blood vessel walls against such plaques.
What do current studies say?
For decades, numerous international epidemiological studies have been carried out researching LDL cholesterol levels considered healthy as well as those considered pathological. The results are becoming more and more evident: The higher the LDL cholesterol levels, the more unfavourable they are for health. Recently, ever-decreasing “standard LDL cholesterol levels” have been introduced and many people are suspicious about whether they are in fact legitimate. Today we know that, generally speaking, there are no standard LDL cholesterol levels. It largely depends on other factors whether a certain LDL cholesterol level is considered problematic or not. Whereas for one person, a certain level might not cause any problems, it could actually be dangerous for another person.
Due to the different properties of HDL and LDL cholesterol, the overall cholesterol level (merely determined for arithmetic reasons by the laboratory) is of minor importance. What is more relevant is how high or low the HDL cholesterol level is.
Numerous primary and secondary prevention studies have shown that both too high levels of “bad” LDL cholesterol as well as too low levels of “good” HDL cholesterol can, independently from each other, lead to premature arteriosclerosis.
In men, HDL cholesterol levels below 40 mg/dl and in women, levels below 50 mg/dl are considered critical. Low HDL cholesterol levels can, in particular, be improved through regular cardio exercise and, to a lesser extent, through a diet rich in high-quality fatty acids (e.g. Omega 3).
On the other hand, an HDL cholesterol level that is too high can be “too much of a good thing” and is not necessarily associated with a particularly low vascular risk.
What is even more complicated is the meaning hidden behind “bad” LDL cholesterol. In addition to smoking and diabetes mellitus, this cholesterol group is considered to be a main risk factor for heart attack. The higher the potential risk, the lower your LDL cholesterol levels should be. This is why therapeutic goals are defined instead of standard LDL cholesterol levels.
In cases of a slightly increased risk of heart attack (only few other risk factors), the European Society of Cardiology recommends an LDL cholesterol level of below 115 mg/dl. If there is an intermediate risk of heart attack (multiple, serious risk factors), an LDL cholesterol level of below 100 mg/dl is recommended. And if there is an extremely high risk (e.g. previous heart attack), the recommendation is to keep the LDL cholesterol level below 70 mg/dl.
On the other hand, an LDL cholesterol of up to 190 mg/dl does not automatically present a problem, as long as there are no other risk factors. So if you do not smoke, have no family history of heart attack, do not have high blood pressure, diabetes mellitus or a fat metabolism disorder, you do not necessarily have to lower your cholesterol level – not even if you have an “increased” overall cholesterol level.
Your LDL cholesterol level is primarily genetically determined and depends on the amount of cholesterol the liver has been “programmed” to produce. Contrary to earlier scientific beliefs, you can hardly influence your cholesterol levels through your diet, as only a very small amount of dietary cholesterol can actually be absorbed by your digestive system. So the idea of being able to reduce the cholesterol in your blood through a “low cholesterol” diet is merely a myth of the last century.
Previous recommendations stating that you should eliminate meat, eggs and butter from your diet will definitely not lead to the desired result!
However, you can lower your LDL cholesterol levels through regular exercise. Especially cardio types of exercise, such as jogging, cycling, swimming, etc. “consume” a lot of LDL cholesterol. Ideally, you can lower your LDL cholesterol by up to 20% by doing a type of cardio exercise two to three hours a week.
However, your LDL cholesterol level cannot be lowered much further with exercise alone. For people with diabetes mellitus, high blood pressure or other heart attack risk factors, a “normal” cholesterol level might already be too high, especially if cholesterol deposits have already been found in their arteries.
In such cases, it is recommended that they take cholesterol-lowering medication that includes statins. These medical agents have been used for in medicine for three decades now, which has allowed us to gain long-term clinical experience with its use. Atorvastatin and rosuvastatin are the most commonly prescribed medications that include this particular group of agents, as they have proven to be most effective and are best tolerated. But simvastatin or pravastatin are also commonly used. All of these substances do not only inhibit the cholesterol synthesis in the liver. They also have plaque stabilizing effects (pleiotrope). This justifies their use for atherosclerosis therapy, even if the LDL cholesterol level is relatively low.
Many people worry about the side effects and long-term effects of such a therapy, which is usually long-term. Occasionally, the therapy might cause muscle pain. It rarely causes liver damage or blood disorders; and the latter can be excluded by taking regular blood tests. These side effects are usually reversible after discontinuation or dose reduction of the medication and can often be completely avoided by using a different statin. In general, these medical agents are tolerated very well and have repeatedly proven effective in both primary and secondary prevention in numerous studies.
Of course, it is not necessary to take statins when your cholesterol levels are only “slightly elevated” and you have no other relevant risk factors. On the other hand, people with seemingly “normal” cholesterol levels would benefit from such a therapy if their individual risk profile, according to statistics, is over 10% for a heart attack within the next ten years. Risk assessment must include all risk factors and individual circumstances of a person and cannot be based on blood tests alone.
During your medical check-up, all of your risk factors will be taken into account and you will receive an assessment of your personal risk profile. This way, you can make an informed decision on whether or not you wish to take a statin (long-term). This is not an easy decision , especially if you have never had to take tablets before. This type of therapy can bring about significant change – but too much LDL cholesterol does not even “hurt”.
On the other hand, a statin therapy can be a real opportunity to reduce the risk of a heart attack. Besides a stroke, a heart attack is still the leading cause of death in industrialized countries, followed – at quite a distance – by cancer.
Finally, it needs to be stressed that not smoking, a balanced (not “low-cholesterol”!) diet and, above all, regular exercise remain the most important therapeutic principles to protect the arteries against atherosclerosis and thus prevent a heart attack or stroke.