Is the cholesterol in the human body caused by what we eat?
Most people believe that the increase in cholesterol in the blood vessels is due to consuming high-cholesterol foods like animal organs. However, this is not the case. The vast majority of cholesterol in the human body is synthesized by the body itself, with only a small amount coming from dietary cholesterol. The liver is the main site for cholesterol synthesis. The raw materials for cholesterol synthesis, such as triglycerides, mainly come from the breakdown of sugars, followed by the breakdown of dietary fats and body fats. Therefore, even if there is no cholesterol in food, the body can still synthesize it on its own.
Thus, to avoid high cholesterol, paying attention to the cholesterol content in food is almost ineffective. As a result, the 2015-2020 Dietary Guidelines for Americans no longer recommend a specific intake level for cholesterol, but instead suggest minimizing intake as much as possible.
In fact, cholesterol plays a certain role in the human body and is an essential substance.
Brain, Cell Membranes, Bile, and Hormones
Cholesterol is actually widely present in the human brain, nerves, skin, and other locations, serving the function of synthesizing bile, vitamin D, hormones, and other essential substances for the body. These hormones include glucocorticoids, mineralocorticoids, and sex hormones.
According to anatomy, the human brain is composed of 60% fat, and cholesterol is an important component of the brain. Additionally, the human body is made up of approximately 100 trillion cells, with cholesterol accounting for about 30% of cell membranes. Cholesterol is used to maintain the strength and fluidity of cell membranes. Why is this?
The hydroxyl group of each cholesterol molecule interacts with water molecules around the membrane, and through interactions with phospholipid fatty acid chains, cholesterol increases membrane packaging, which alters membrane fluidity while maintaining membrane integrity. This allows animal cell membranes to remain stable and durable without becoming rigid, enabling animal cells to change shape and allowing movement. Our bodies indeed need cholesterol to build healthy cells.
It is also important to mention that cholesterol is a crucial component in repairing blood vessel walls.
Is there a distinction between good and bad cholesterol?
Common tests include the following data: total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol.
Transport within the body relies on "lipoproteins," which come in various sizes. HDL is high-density lipoprotein, responsible for transporting cholesterol in the blood back to the liver, while LDL is low-density lipoprotein, which carries cholesterol from the liver to various tissues through the bloodstream. They are proteins rather than cholesterol, acting as trucks for transporting cholesterol, and the number of trucks depends on the volume of goods being transported, not because these proteins cause high cholesterol.
Therefore, the values of HDL and LDL in test reports reflect the transportation status of cholesterol in the body. The levels are related to various factors such as individual constitution, diet, exercise, stress, and genetic diseases.
As for patients with "excessive" cholesterol, whether treatment is needed or what type of treatment to use will depend on the analysis and evaluation by doctors, who will provide different recommendations based on each individual's condition, and cannot be generalized.
High cholesterol may lead to fat deposits in the blood vessels. The increase in deposits can eventually hinder sufficient blood flow through the arteries. Deposits may also suddenly dislodge and form blood clots, leading to heart attacks or strokes.
High cholesterol may have a genetic component, but is mostly caused by unhealthy lifestyles, making it preventable and treatable.
Prevention is better than cure
A healthy lifestyle can not only lower your cholesterol but also help you avoid high cholesterol. To prevent high cholesterol, you can:
• Exercise basically every day of the week, for at least 30 minutes each time
• Consume beneficial fats appropriately and avoid trans fats
• Lose excess fat and maintain a healthy weight
• Quit smoking
• Limit alcohol consumption (if unable to quit completely, drink in moderation)
• Manage stress
Other diseases that may lead to high cholesterol levels include:
• Diabetes
• Liver or kidney diseases
• Polycystic ovary syndrome
• Pregnancy and other conditions that increase female hormone levels
• Hypothyroidism
Since cholesterol is also an important component in repairing blood vessel walls, we should avoid excessive cholesterol production from the source, which means taking good care of our blood vessels. Controlling blood sugar is crucial.