23 Sep 2022
The Good, the Bad, and the Not-So-Bad: The Complex Roles of Cholesterol
Estimated read time: 5 minutes
In very simple terms, people learn that there is good cholesterol, HDL, which fights the bad cholesterol, or LDL. HDL particles “patrol” blood vessels, remove the LDL cholesterol particles and plaque lining the artery walls, and carry their fatty cargo to the liver for elimination. But the full story is much more complicated.
Cholesterol, a pale yellow waxy lipid, is a type of fat that is essential for life. It must be maintained at a good level, since an excess of cholesterol in the body can impact health. Cholesterol is the main component of cell membranes, and its multiple “jobs” range from building tissues to regulating hormones and processing vitamin D.
Cholesterol can be a person’s best friend or their worst enemy — it all depends on how much of it is circulating in your body. In the right amount, it does its job so the body can function. But if there is too much of it in the blood, it can combine with other substances and form plaque, which over time can stick to the walls of blood vessels. This buildup is known as atherosclerosis and the condition it causes is called coronary artery disease.
If this buildup is not prevented, coronary artery disease can lead to blood clots, heart failure, and arrhythmias. It also raises the risk of stroke. Simply put, the heart and arteries begin to become dysfunctional, and one’s life may be at risk.
Although there is a genetic factor that determines an individual’s cholesterol levels, the ways to regulate cholesterol include having a healthy lifestyle and diet, exercising, and maintaining a healthy weight. Now, new research may add another potential treatment discovered in the human body itself: gut bacteria. These are the “good” bacteria that live in our intestines and which have successfully balanced cholesterol in laboratory mice.
While science is constantly researching and working to develop new treatments to control cholesterol, there are still basic issues that need to be explained or clarified if we wish to fully understand the importance of this vital substance.
The Many Faces of Cholesterol
Our bodies produce almost all of the cholesterol they need, with the liver acting as the main “factory.” But this fat is also found in animal source foods such as egg yolks, meat, and cheese. In both cases, cholesterol is made up of:
- High-density lipoprotein. Known as HDL or “good” cholesterol, because it carries excess cholesterol back to the liver for elimination.
- Low-density lipoprotein. Known as LDL or “bad” cholesterol, because high LDL levels lead to the buildup of arterial plaque.
- Very low-density lipoprotein. Known as VLDL, it is also sometimes described as “bad,” because it plays a role in the process of atherosclerosis; VLDL particles carry triglycerides, another type of fat, to tissues. There is no simple, direct way to measure VLDL cholesterol, so it is usually not mentioned during routine screening tests.
In the United States and in many other countries, cholesterol level is measured in milligrams. Having a total cholesterol level of less than 200 mg is ideal. Between 200 mg and 239 mg is considered borderline high, while more than 240 mg is defined as high cholesterol. The blood tests that analyze cholesterol levels also break it down by HDL, LDL, and VLDL, so the person and doctor can see each number in detail and flag the any warning signs.
It is recommended to get a cholesterol test for the first time between the ages of 9 and 11, and then every five years, as long as the numbers remain in the normal range.
Avoidable Risk Factors
In Latin America and the Caribbean, low levels of HDL or good cholesterol is the most common lipid disorder, as shown by research published in eLife. This contributes to the high incidence of cardiovascular disease, which is responsible for the majority of deaths among men and women in the region.
There are numerous reasons why some people have low HDL and others have high HDL. Genes appear to play the most important role in determining how much good cholesterol the body produces and the proportion of different subtypes.
But lifestyle also affects HDL levels. Smoking, being overweight, and a lack of physical activity tend to lead to lower HDL cholesterol. The same applies to a diet rich in refined carbohydrates (white bread, sugars).
As with so many other conditions, in order to keep the two types of cholesterol at the levels needed by our bodies, experts recommend sticking to good lifestyle habits:
- Maintaining a healthy weight and a diet rich in vegetables and low in sugars and fats.
- Regular exercise: even simple activities like long walks help enormously.
- Not smoking, or stopping smoking.
- Avoiding excessive alcohol use.
When Healthy Habits are not Enough
However, since age is also an important factor, it is possible for an adult, especially over 40, to require medication in order to maintain a healthy cholesterol level. Some of the most popular medications include:
- Statins, which prevent the liver from producing cholesterol.
- Bile acid sequestrants, which decrease the amount of fat absorbed from food consumption.
- Cholesterol absorption inhibitors, which lower the amount of cholesterol absorbed from food and reduce triglycerides (a type of fat found in the blood).
- Nicotinic acid (niacin), which reduces bad cholesterol (LDL) and triglycerides, while increasing good cholesterol (HDL).
- PCSK9 inhibitors, which block a protein called PCSK9. This helps the liver remove and eliminate bad cholesterol from the blood.
- Fibrates, which reduce triglycerides. Fibrates can also increase good cholesterol (HDL).
- Combination medications, which include more than one type of cholesterol-lowering medicine.
In all cases, it is essential to consult a primary care physician, who will order the necessary tests and prescribe the appropriate medication. This is a very important step in order to determine the right combination of drugs, if needed, and to avoid interactions with other drugs that could trigger side effects.
In the near future, we may add to this list the use of the microbiome, or the gut bacteria mentioned above _— a group of good germs called bacteroides that are produced by the body itself and are already associated with the food process. This is a path that science is now beginning to research, which focuses on the human body itself as a potential source of cholesterol-fighting agents.
Remember, always consult with your physician or health care professional to determine the best options for your body and health and to answer any questions you may have regarding any medical matter.