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General Information on Cholesterol

In the human body, cholesterol is a vital molecule that is incorporated into cell membranes and is essential for the production of hormones, Vitamin D and bile acids. Cholesterol can be obtained from foods and produced by the liver itself.

Individual meals have only a limited impact on cholesterol levels. Long-term dietary habits and genetic factors are crucial for regulation.

The Different Types of Cholesterol: LDL and HDL

There are two main types of cholesterol: Low-Density Lipoprotein (LDL) and High-Density Lipoprotein (HDL).

• LDL Cholesterol:
  Often referred to as "bad" cholesterol, LDL transports cholesterol from the liver to the cells. However, when there is an excess, it can deposit on the artery walls, leading to plaque formation and an increased risk of heart diseases.

• HDL Cholesterol:
  In contrast, HDL cholesterol is known as "good" cholesterol. It transports excess cholesterol back to the liver for breakdown, contributing to the cleansing of the arteries.

• Triglycerides:
  Besides LDL and HDL, the level of triglycerides in the blood is also significant. Triglycerides are a form of fat in the blood that serves as an energy reserve. Elevated triglyceride levels can also increase the risk of cardiovascular diseases.

Cholesterol Metabolism in the Body

The liver is the origin of cholesterol synthesis, starting with the production of very-low-density lipoprotein (VLDL). This undergoes a series of transformations, becoming intermediate-density lipoprotein (IDL) and eventually low-density lipoprotein cholesterol (LDL-C). LDL-C acts as a transporter, carrying cholesterol to the cells, where it is used as a building block for various cellular functions.

Although high-density lipoprotein (HDL), also produced by the liver, collects excess cholesterol from the cells and transports it back to the liver and into the intestine for excretion from the body, not all excess LDL-C can be returned in cases of surplus. In such instances, there is a possibility that excess LDL-C may be deposited in the arteries, leading to further health issues.

Good and Bad Cholesterol: Can They Really be Categorized This Way?

Calling HDL "good" and LDL "bad" is a simplification, but that doesn't mean elevated LDL is harmless. LDL particles carry cholesterol in the blood, and higher concentrations of these particles over time contribute to the development of atherosclerosis.

Particle size can provide additional information, but it doesn't make large LDL particles harmless or mean that someone with high LDL cholesterol has nothing to worry about. The overall number of atherogenic particles, often estimated using ApoB, and a person's other risk factors are important too.

Similarly, with HDL particles, it's not just about the total quantity but also their functionality that matters. HDL transports cholesterol from the cells to the liver, where it is broken down or prepared for excretion. However, not all HDL particles may be equally effective.

The efficiency of HDL depends on its antioxidant and anti-inflammatory properties. A high proportion of functional HDL particles is thus important to ensure their protective effect on the arteries.

So, while a single cholesterol value never tells us everything about someone's health, high LDL cholesterol is still an important cardiovascular risk factor. HDL values also need to be interpreted in context. Neither number should be considered on its own.

More Precise Heart Risk Assessment through Measurement of Lipoprotein Particles

A standard cholesterol test already provides useful information about cardiovascular health. However, looking at LDL and HDL cholesterol alone doesn't always tell us everything about the actual risk.

For example, LDL cholesterol measures how much cholesterol is carried by LDL particles in the blood. But it doesn't directly tell us how many of these particles are circulating. And that can make a difference, since a person can have relatively normal LDL cholesterol levels while still having an increased number of potentially harmful particles.

This is where Apolipoprotein B (ApoB) becomes interesting. Each LDL particle and most other lipoprotein particles involved in atherosclerosis contain one ApoB molecule. Measuring ApoB therefore gives us a good estimate of how many of these particles are circulating in the blood.

Especially in people with elevated triglycerides, diabetes or certain metabolic conditions, ApoB can provide additional information that isn't always apparent from LDL cholesterol alone.

There are also advanced laboratory tests, such as NMR Lipoprofiles, that can measure the number and size of different lipoprotein particles. However, measuring particle size isn't automatically necessary for everyone. In many cases, LDL cholesterol and ApoB already provide the information needed for a proper risk assessment.

Of course, cholesterol values shouldn't be evaluated in isolation. Blood pressure, smoking, diabetes, family history and age all play important roles. It also matters how long someone has been exposed to elevated levels of harmful lipoproteins. Having high LDL cholesterol for several decades is obviously different from having an elevated result for a short period.

That's why it's important to look at the overall cardiovascular risk rather than simply checking whether every number falls within the laboratory's reference range.

Lipoprotein(a): The Genetic Risk Factor

Another blood value that deserves much more attention is Lipoprotein(a), usually abbreviated as Lp(a).

Lp(a) is similar to an LDL particle, but it has an additional protein attached to it called apolipoprotein(a). Elevated Lp(a) levels are associated with a higher risk of cardiovascular diseases, including heart attacks and strokes. Research has also linked high Lp(a) levels to calcification and narrowing of the aortic valve.

What's particularly interesting about Lp(a) is that its concentration in the blood is largely determined by genetics. Unlike many other cholesterol-related values, it usually changes very little through diet or exercise. Levels also tend to remain relatively stable throughout adulthood.

For this reason, the European Atherosclerosis Society recommended in 2022 that adults have their Lp(a) measured at least once. And since the value is mainly determined by genetics, one measurement is usually enough for a lifetime. You don't normally need to be fasting either. Certain medical conditions can influence the result, though, so another measurement may occasionally be necessary.

Unfortunately, Lp(a) isn't always included in a standard cholesterol test. If you've never had it measured, it's definitely worth asking your doctor about it.

Values below 30 mg/dL (75 nmol/L) are generally considered to indicate a relatively low additional risk. Between 30 and 50 mg/dL (75 to 125 nmol/L), there's a range of uncertainty, while values above 50 mg/dL (125 nmol/L) are considered elevated and associated with increased cardiovascular risk.

These aren't absolute boundaries between healthy and unhealthy. The risk increases gradually as Lp(a) rises, and the result needs to be considered alongside other cardiovascular risk factors. Also, mg/dL and nmol/L measure Lp(a) differently, so there isn't one exact conversion factor between the two units.

Since Lp(a) is mostly genetically determined, lifestyle changes generally have little effect on the value itself. However, maintaining healthy blood pressure, avoiding smoking, exercising regularly and keeping LDL cholesterol under control can still help reduce the overall cardiovascular risk. An elevated Lp(a) level doesn't mean that developing cardiovascular disease is inevitable.

There is also research into medications specifically designed to lower Lp(a). Several promising substances are already being investigated in clinical trials. Whether lowering Lp(a) with these treatments will actually reduce the number of heart attacks and strokes still needs to be established.

Even if your regular cholesterol results look perfectly normal, knowing your Lp(a) level can therefore provide another important piece of information about your cardiovascular health.

Influence of Lifestyle on Cholesterol Levels

The good news is that, aside from Lp(a), most cholesterol markers can be improved with a few lifestyle adjustments.

The body fat percentage (BFP) plays a significant role in this context. If your BFP is well above the healthy range, there is an increased risk of adverse changes in the lipid profile.

People with a higher body fat percentage tend to have elevated triglyceride levels and lower HDL cholesterol. Additionally, obesity can lead to insulin resistance, influencing the cholesterol metabolism.

Therefore, it is crucial, as a first step, to achieve a healthy normal weight, which is only possible through a caloric deficit. You can find all the information about this here: Nutrition Basics

In addition to maintaining a healthy body weight, fitness also plays a crucial role in regulating cholesterol levels. Regular physical activity, ideally through a combination of strength and endurance training several times a week, can contribute to increasing HDL cholesterol.

Two other factors that can negatively impact cholesterol levels but are often overlooked are smoking and chronic stress. These aspects should not be underestimated. The harmful effects of smoking are widely known nowadays, rapidly increasing the risk of cardiovascular diseases. In stressful situations, stress hormones like cortisol are released, leading to an elevation of LDL cholesterol. So, the advice is clear: Refrain from smoking and implement strategies for stress management.

Influence of Diet on Cholesterol Levels

Anyone familiar with my nutrition articles, especially "Sugar Facts", can probably guess what's coming next. In today's time, it should generally be known that individual foods rarely constitute the main issue. This also applies to cholesterol obtained through diet.

Eggs, in particular, have long been criticized for their high cholesterol content. However, the consumption of specific foods only leads to a slight increase in blood cholesterol levels, as the body can reduce its own production when taking in a lot of cholesterol from external sources.

As with all foods, the rule applies here: The quantity in the long run makes the poison.

Aside from that, it's not the cholesterol content of foods that matters, but rather the type and amount of dietary fats consumed.

A healthy and balanced diet should focus on the intake of unsaturated fats. The 80/20 rule, which suggests that a healthy diet should consist of about 80% nutritious foods and 20% treats, is applicable here as well. Occasionally enjoying foods with saturated fats or trans fats does not necessarily lead to cholesterol problems, as long as overall attention is paid to a balanced diet.

Additional Possible Causes of Poor Cholesterol Levels

The causes of high LDL-C and low HDL-C levels in most people can be attributed to their lifestyle. But what if someone is not overweight, has already optimized their diet and still has poor cholesterol levels?

In such cases, various medical conditions such as hypothyroidism, diabetes mellitus, or chronic kidney insufficiency, or the use of certain medications like birth control pills, beta-blockers, diuretics, or glucocorticoids could be the cause of elevated cholesterol levels.

And if none of these scenarios apply, there may be a genetically inherited condition known as familial hypercholesterolemia.

Medication for High Cholesterol Levels

If, despite optimizing diet and lifestyle, cholesterol levels cannot be sufficiently improved, medication may be considered. This is particularly relevant for genetically determined or persistent cholesterol issues. The decision for medication should, of course, be made in consultation with a specialized doctor.
Common medications used to treat cholesterol levels include:

• Statins:
  Statins are a frequently prescribed class of medications that aim to reduce cholesterol production in the liver. They inhibit an enzyme responsible for cholesterol synthesis, thereby lowering LDL cholesterol levels.

• Ezetimibe:
  Ezetimibe is another medication that blocks the absorption of cholesterol from food in the intestines. It can be prescribed alone or in combination with statins to regulate cholesterol levels.

• PCSK9 Inhibitors:
  PCSK9 inhibitors are a class of medications that reduce the amount of LDL cholesterol in the blood by blocking a protein that normally promotes the breakdown of LDL cholesterol. These medications are often used in individuals with genetically inherited hypercholesterolemia.

• Fibrate Preparations:
  Fibrates work by lowering triglycerides and increasing HDL cholesterol levels. They are more commonly prescribed when high triglyceride levels are a specific concern.

• Bempedoic Acid:
  Bempedoic acid is a medication that inhibits cholesterol synthesis in the liver, thereby lowering LDL cholesterol levels.

Saturated & Unsaturated Fatty Acids

Fats are categorized into saturated and unsaturated (including monounsaturated and polyunsaturated) fats.

• Saturated Fats:
  Foods such as sausages, fatty meats, and butter contain saturated fats. Long-term consumption of high amounts of saturated fats can lead to an increase in LDL cholesterol.

• Unsaturated Fats:
  Monounsaturated fats, found in nuts and avocados, especially in the form of ALA (Alpha-Linolenic Acid), can help lower LDL cholesterol and increase HDL cholesterol with long-term consumption.
  Polyunsaturated fats, especially EPA and DHA (Eicosapentaenoic Acid and Docosahexaenoic Acid), primarily found in fatty fish, can also lower LDL cholesterol with long-term consumption and provide additional cardiovascular health benefits.

• Trans Fats:
  Trans fats are specific fatty acids found in industrially processed foods like cookies, french fries, and margarine. Long-term consumption of trans fats can increase LDL cholesterol and simultaneously decrease HDL cholesterol.

Overview of Omega Fatty Acids

It can be confusing to keep track of saturated, unsaturated, monounsaturated, polyunsaturated, trans fats, LDL and HDL. And then there are omega fatty acids, adding another layer to the puzzle. To clarify, I've created a brief list. Here are the omega fatty acids and their roles:

• Omega-3 (ALA):
  Sources: Walnuts, flaxseeds, chia seeds.
  Benefits: ALA is an essential polyunsaturated fatty acid that the body cannot produce on its own. It plays a crucial role in inflammation regulation and supports heart health. ALA contributes to increasing HDL cholesterol and has positive effects on LDL cholesterol.

• Omega-3 (EPA/DHA):
  Sources: Fatty fish species (e.g., salmon, mackerel).
  Benefits: EPA and DHA are long-chain omega-3 fatty acids that are particularly important for cardiovascular health. They help lower blood fats and inflammation and support brain function. EPA and DHA can lower LDL cholesterol while increasing HDL cholesterol.

• Omega-6 (Linoleic Acid):
  Sources: Vegetable oils (e.g., sunflower oil, soybean oil), nuts.
  Benefits: Linoleic acid is a polyunsaturated fatty acid crucial for cell growth and hormone formation. A balanced ratio with Omega-3 is crucial for health. It influences both LDL and HDL cholesterol.

• Omega-9 (Oleic Acid):
  Sources: Olive oil, nuts (e.g., almonds), avocados.
  Benefits: Oleic acid is a monounsaturated fatty acid. It supports heart health, promotes insulin sensitivity and contributes to anti-inflammatory effects. Oleic acid can lower LDL cholesterol and increase HDL cholesterol.

Omega 3 Facts

Is it sufficient to eat only walnuts for Omega-3?
No, it is not sufficient to rely solely on walnuts to meet the Omega-3 fatty acid needs. While walnuts are a good source of Omega-3 (ALA), the body has limited ability to convert ALA into the essential long-chain Omega-3 fatty acids EPA and DHA. Therefore, it is advisable to include sources of EPA and DHA, such as fatty fish or algae oil, in the diet in addition to walnuts.

Can't I just take a combination supplement (Omega 3-6 or 3-6-9)?
Combination supplements are not recommended and may even lead to an imbalance. The ideal balance between Omega-3 and Omega-6 fatty acids is often recommended in a ratio of 1:1 to 1:4. However, this ratio is often disrupted in modern diets, as many processed foods are rich in Omega-6 fatty acids and low in Omega-3 fatty acids.

Similarly, Omega-9 fatty acids are present in many everyday foods and do not need to be supplemented separately. Additionally, the body can synthesize Omega-9 fatty acids on its own and is therefore not considered essential.

Creating an Omega-3 Index
The Omega-3 Index (O3Ix)  provides information about the proportion of EPA and DHA in red blood cells. A higher index is associated with a lower cardiovascular risk. A blood test can be useful to assess the Omega-3 status. Based on the results, you can then consider whether supplementation of Omega-3 fatty acids is necessary.

With an average diet, the O3Ix for most people is around 4-6%. Regular consumption of fatty fish could raise the O3Ix to 6%. However, an optimal Omega-3 Index falls in the range of 8-11%, which is why supplementation can indeed be beneficial in many cases.

Practical Implementation of Fat Intake in Daily Life

The integration of different fats into your diet can be accomplished in the following ways:
For frying foods, refined olive oil or rapeseed oil are excellent choices. Thanks to their high smoke points, they are ideal for preparing dishes in a pan. Refined olive oil is suitable for salads and dressings, as it may not be suitable for frying but works exceptionally well for dressings.

Nuts, about a handful (approximately 30g) per day, make for a delicious snack. However, it's advisable to keep track of the quantity, as nuts are calorie-dense. Consuming fatty fish like salmon, mackerel, or herring two to three times a week provides an excellent source of DHA and EPA, essential Omega-3 fatty acids. Alternatively, consider Omega-3 fish oil capsules, especially if fish is less frequent in your diet. For vegans, Omega-3 algae oil capsules can be considered as a dietary supplement.

And then there's room for indulgence. Every Wednesday, there's a movie night on the schedule, accompanied by nachos and cheese sauce. On the weekends, we treat ourselves to a serving of fries and a burger, completely okay without directly affecting cholesterol levels.

Because if 80% of your diet is balanced, you can enjoy the remaining 20% without any concerns.

Closing Words

So, let's summarize: It is not necessary to worry about cholesterol levels due to individual meals. As always, the overall diet is crucial when considered in the long term. And if you've drawn the genetic short straw, medical advice is necessary anyway.

I hope I could clarify the topic comprehensibly. As always, please do not make independent medical decisions or changes to your medication based on this information. Consult with a medical professional for clarification.