What is Cholesterol?
Cholesterol is often viewed negatively by health and fitness enthusiasts, but it serves a critical role in our bodies. All animals create many important hormones using cholesterol as the precursor. Estrogen, testosterone, and corticosteroids–which are involved in many bodily functions such as regulating inflammation and metabolism–are composed of cholesterol.
What is “Good” and “Bad” Cholesterol?
Cholesterol is transported through the blood with two primary proteins, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). You may have heard of these: LDL is often called “bad” cholesterol while HDL is called “good” cholesterol. However, cholesterol transport by both LDL and HDL is necessary.
These transporters ensure enough cholesterol is present within every cell to allow hormones to be created. Some cells rely on LDL for cholesterol transport, and others rely on HDL, so both are important and necessary.
What Problems Occur When LDL is High?
If you eat foods high in cholesterol, your body will start to create a modified form of LDL that doesn’t transport cholesterol. Your body won’t need to transport cholesterol from cell to cell, because each cell already has enough cholesterol.
However, your body will still create LDL (in its modified form), which will be taken up by some blood cells. These blood cells will then become distorted and have a high likelihood of becoming trapped in a blood vessel. Ultimately, this can cause plaque to form within the blood vessel. Large enough plaques prevent blood flow and can lead to a heart attack or stroke.
Although LDL is not technically a form of cholesterol, many blood tests look for the amount of cholesterol being transported by LDL, HDL, and other carrier proteins. If LDL is responsible for a large amount of cholesterol transport in your body, this may be at risk of developing heart disease. This is at least part of the reason why LDL has been mistakenly called “bad” cholesterol.
What are the Benefits of High HDL?
Like LDL, HDL is a transporter of cholesterol in the blood. One of the roles of HDL is to carry cholesterol to the liver for digestion and excretion (removal). This is associated with better outcomes, particularly for heart disease, because the removal of excess cholesterol may reduce the amount of modified LDL your body creates.
In turn, this will reduce the buildup of plaques from blood cells taking in the abnormal form of LDL and subsequently becoming trapped in the blood vessel.
Again, HDL is not a form of cholesterol, but rather a transporter of cholesterol. The important thing to remember here is cholesterol, and its carrier proteins are neither good nor bad on their own. These indicators give doctors a good idea of what’s happening inside your blood vessels and how to reduce the risk of cardiovascular disease.
So, is Cholesterol Good or Bad?
Popular health information often distinguishes between “good” and “bad” forms of cholesterol, but this is incorrect. Cholesterol is an important substance in the body and only comes in one form. Different carrier proteins are responsible for transporting cholesterol throughout the body. Again, these proteins are essential for overall health, and neither one is good nor bad on its own.
When the system becomes imbalanced, problems with circulation can occur. This is why your doctor is concerned with your overall cholesterol level and even your LDL and HDL levels. Knowing these numbers can help your doctor assess your risk for heart disease.
How Can I Lower LDL, Raise HDL, and Balance Cholesterol to Reduce the Risk of Heart Disease?
Clinical guidelines recommend reducing daily cholesterol intake as much as possible. Since we can produce enough cholesterol from nutrients in our diet, eating foods high in cholesterol can contribute to elevated cholesterol levels in the blood. Ultimately, this might cause the body to create an abnormal form of LDL, increasing the risk of developing plaques in your blood vessels.
Another recommendation is to maintain a healthy weight. If you are overweight, your body’s metabolism functions differently and may not be able to remove excess cholesterol as easily. In some cases, losing weight may be more important than modifying your diet. According to one group of scientists, people who were overweight had higher cholesterol (and higher LDL) than people in a healthy weight range. This relationship was stronger than any between diet and cholesterol levels. In other words, diet had less impact on cholesterol levels than merely maintaining a healthy weight.
Keep in mind…
It’s important to remember that many factors affect cardiovascular health. Cholesterol is only one element that contributes to heart health or disease. Many other factors, including diet and lifestyle, are essential to improving and maintaining the function of the heart and blood vessels. Understanding the relationship between cholesterol, LDL, and HDL can help you take charge of your health.
The next time you visit your doctor, you’ll be better equipped to discuss the results of your cholesterol test and strategies to reduce cholesterol naturally if it is too high. Awesome!
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