Does cholesterol scare you? We aren’t surprised. In all fairness, however, cholesterol deserves some credit. This waxy, fat-like substance is naturally made in all parts of the body.
Does cholesterol scare you? We aren’t surprised. Cholesterol has received nothing but negative publicity and a bad name. In all fairness, however, cholesterol deserves some credit. This waxy, fat-like substance is naturally made in all parts of the body. Why? Well, because your body needs it to function properly. See, cholesterol itself isn’t bad. Here are a few reasons why:
It’s an important part of our cell membranes, the layer that surrounds each and every one of our cells. It even surrounds the tiny organelles inside our cells. Without cholesterol, the cells of our body would have no stability or firm structure. In other words, they would turn into mush.
Our brain is rich in cholesterol. In fact, about 25% of the body’s cholesterol is found here. The entire nervous system relies on cholesterol to protect the proteins that are involved in cell communication.
Do you remember what you did yesterday? Someone you met last week? Or something you learned 10 years ago? You can thank cholesterol. Cholesterol is part of the myelin “coat” that insulates our nerve cells. This makes memory possible. Interestingly, memory loss has been identified as a side effect of cholesterol-lowering drugs, like statins.
Even the endocrine system uses cholesterol to make hormones, such as steroid or sex hormones. These hormones are involved in important functions such as metabolism, muscle formation, and reproduction.
Without cholesterol, your healthy diet would be in vain. Cholesterol is used to make bile, which helps us absorb the essential fat-soluble vitamins A, D, E and K. The body even uses cholesterol to make vitamin D.
Clearly, it’s important to have a balanced view of cholesterol. It’s not a lethal poison. It’s required to stay healthy. However, you may be wondering what all this talk of “good” and “bad” cholesterol is all about?
LDL and HDL
When your doctor talks to you about cholesterol, he will mention two “types”: LDL and HDL. These are, in fact, cholesterol “carriers”. They both carry the same cholesterol but to different locations.
LDL (which stands for low-density lipoprotein) carries cholesterol from the liver TO organs and tissues. Over time, LDL in your bloodstream can start to build up and deposit on the walls of your blood vessels. These deposits, called plaques, can narrow your blood vessels to the point of blocking them. This increases the risk of heart disease. Because it carries and dumps cholesterol and other lipids (such as triglycerides) throughout your body, LDL is generally referred to as your “bad” cholesterol”.
HDL (which stands for high-density lipoprotein) carries cholesterol FROM organs and tissues back to the liver for removal or recycling. This is known as reverse cholesterol transport because it transports cholesterol from the blood and returns it to the liver (the reverse of what LDL does). Much like a garbage truck, HDL keeps LDL cholesterol from lingering in the blood vessels or building up and lodging on artery walls. In fact, it also picks up other fats (called lipids) such as triglycerides and carries them AWAY from the arteries and BACK to the liver, to be removed. Because of this, it is generally known as your “good” cholesterol.
Higher HDL or Lower LDL: Which is most important?
Since there are no symptoms for unhealthy cholesterol levels, a blood test can help detect abnormal levels. Many people, especially physicians, zero in on LDL cholesterol. For several decades, they only focus on getting LDL cholesterol levels down. Treatments, diets, and medication (such as statins) have been designed to focus on lowering LDL. Millions of Americans take statins to lower their LDL in the hope that their health will improve. Is this enough, though? Will it lower their risk of dying from heart disease? Will these drugs (which pharmaceutical companies make billions of dollars from) increase their lifespan? Current research shows that this simplistic approach is outdated, misleading, overestimated, and narrow-minded. Unfortunately, it ignores a more important number—your HDL levels.
A study by researchers from Indiana University School of Medicine and pharmaceutical company GlaxoSmithKline, Inc wanted to find the greatest risk factors for future heart attacks. What risk factors are the strongest for predicting future heart attacks? The results published in the American Heart Journal found that after previous heart disease and age, a person’s HDL level is the strongest predictor of future heart attacks. HDL made it in the top three risk factors for heart disease. Did you notice how its importance outweighs even body weight (such as obesity) and gender?
It may not surprise you, then, that the American Heart Association’s “cardiovascular risk calculator” now counts HDL levels, not LDL, when assessing heart disease risk.
Clearly, more good cholesterol (HDL) is more important that less bad cholesterol (LDL). The study also discovered that HDL levels were a strong predictor of stroke and that LDL cholesterol levels are not. (American Heart Journal, Volume 151, Issue 3, March 2006, Pages 755.e1-755.e6)
HDL: What Happens When Low?
HDL levels are an important, if not the most important part of a blood panel. Why? By removing excess LDL cholesterol, HDL helps slow the buildup of plaque. Your blood HDL levels are basically telling you how good of a clean-up job your body is doing.
Consider what happens when your HDL levels are low. This can increase your risk of heart disease. Interestingly, certain genetic diseases that cause low levels of HDL, like Tangier disease, fish-eye disease and diseases linked to apo A1 gene mutations, are commonly linked to heart disease. (Rev Esp Cardiol. 2004;57:557-69. Vol. 57 Num.06)
HDL is involved in signaling other molecules in your bloodstream and telling them what to do. Think of the important role a manager, boss, or director of a team or department is in making sure everything runs smoothly. Similarly, HDL cholesterol directly communicates with cells of your immune system (T cells and macrophages) as well as cells that make up the walls of your blood vessels. What would happen if you had fewer HDL to carry out this job? Or, even worse, what would happen if the quality of the HDL you do have is poor?
If you don’t take care to keep your HDL levels up and running, HDL will slow down and eventually lose its ability to do all the good things it does for your body. It may even become damaged. This can lead to heart disease.
Just how does plaque buildup happen in the arteries? The “bad” LDL cholesterol will start to lodge in artery walls. Free radicals oxidize this LDL and lead to inflammation. Certain cells of your immune system come to ingest the oxidized LDL but, in the process, they become foam cells. These foam cells deposit in the walls of the blood vessel and a tough layer forms around it. Plaque is born. It will now reduce blood flow, cause blood clots, and over time cause a heart attack or stroke.
HDL: What Happens When High?
What would happen if there was more HDL in the picture? Conversely, a healthy level of HDL can protect against heart attack and stroke. Merely lowering LDL cholesterol levels may not be enough to lower the risk of heart disease. As previously mentioned, HDL clears the blood of LDL or “bad” cholesterol. It can even reduce chances of heart attack or stroke without any changes to LDL. The higher the HDL, the less LDL you will have in your blood. We repeat: the higher the HDL, the more LDL you’ll be able to get away with.
HDL as an Antioxidant: Protect your Circulation
When you think of a healthy body, what systems or organs usually come to mind? Your digestive system? Your brain, lungs, bones, and heart? These are all important. However, your circulatory system’s health is just as important. How healthy is your endothelium? The endothelium is the inner wall of your blood vessels. Damage to the endothelium leads to atherosclerosis (heart attacks/strokes).
A damaged endothelium allows toxins and other unwanted invaders in the blood to enter the vessel and begin the process of inflammation and plaque formation. This ultimately leads to the formation of a potentially deadly clot.
HDL protects the endothelium. Not only does HDL clean the blood of excess LDL, but it also prevents LDL from oxidizing and becoming rancid. Much like vitamin C, E, or other antioxidants, HDL has enzymes (like paraoxonase1 or PON1) that make it an antioxidant. These antioxidants protect HDL itself from oxidizing. Why does LDL need an antioxidant? If LDL oxidizes, this leads to atherosclerosis, plaque buildup, and heart disease.
If you already have plaque on your artery walls, studies have shown that high levels of high-quality HDL can detach LDL cholesterol that have already lodged onto your artery walls.
Pitfalls of LDL: Does Lowering it Make a Difference to your Health Risk?
A valuable lesson was learned from a large scale clinical controlled trial called the Women’s Health Initiative. Almost 49,000 women followed a special diet and focused on lowering cholesterol. Even though LDL was “significantly reduced”, the results showed that after an average of 8 years, this did not significantly reduce their risk of cardiovascular disease, heart attack, or stroke. In other words, lowering their LDL did not cut their risk.
Consider another randomized trial—the Multiple Risk Factor Intervention Trial (or MRFIT trial). A group of about 13,000 high-risk men were followed for seven years. Half of the group received specialized counseling, treatment, and care to, amongst other things, lower their cholesterol. Researchers expected their death rates and health risks to drop compared to the other half of the group. Results, however, showed that the death rates were still the same. No significant changes were seen by lowering their cholesterol.
The truth is, although many in the medical field say LDL must be lowered, they are not 100% certain this is, in fact, the right thing to do. One study conducted in northern Italy followed more than 3,000 and kept a close eye on their LDL for 12 years. The researchers found that heart failure risk and death rates decreased with high LDL. True, they did find that high LDL levels had an increased risk of heart attack. However, it cannot be ignored that results were inconsistent regarding LDL’s role in heart health. Why did death rates decrease even though people had high LDL? Could it be that LDL is not what we should be focusing on?
Could it be that some people who have moderately high LDL can still be generally healthy as long as their HDL levels are high? It turns out that many with normal or low LDL can be at HIGH risk. Notice what one study published in the American Heart Journal found. Researchers looked at more than 230,000 patients who have been hospitalized for heart disease only to find that almost half of them were admitted with LDL levels well below 100 mg/dL. Their LDL levels were low, yet they were still hospitalized for coronary artery disease (CAD).
Had anyone looked at their LDL cholesterol levels before hospitalization, they may have jumped to the conclusion that they’re safe, healthy, and heart disease-free. However, why did so many low-LDL people get admitted for CAD? Interestingly, the researchers found that more than half of the admitted patients had HDL below 40. Less than 10% of the patients had a desirable HDL level above 60. Could it be that their low HDL levels were the true problem?
HDL: Where should it be?
According to the AHA, an HDL level
- less than 40 (mg/dL) for women and less than 50 is a major risk factor for heart disease (at risk level)
- 60 and above is protective against heart disease (desirable level)
Remember, a low HDL level puts you at risk for heart disease even if your LDL is low.
“Protective against heart disease.” Those are powerful words that capture the heart-protective benefits of HDL cholesterol. Clearly, you want your HDL to be high. Because of the bad reputation cholesterol has received it may be hard to understand why you would want to raise any cholesterol. Raising your HDL cholesterol and lowering your LDL cholesterol is not a mixed message, however. Now that you are familiar with the two types of cholesterol you can see why. HDL helps clear your blood of excess cholesterol. For 40 years, HDL has been praised for this.
In recent years, modern research has considerably refined our understanding of HDL benefits even more. Consider some of the other health benefits of HDL cholesterol:
- HDL helps nerve-cell synapses mature
- Mice studies show that HDL helps skeletal muscle use glucose more efficiently. This discovery will surely prove useful for efforts in treating and preventing diabetes and preventing problems with blood sugar levels
- HDL can help reduce colon cancer risk because HDL helps reduce inflammation. One study found that just a 16 mg rise in HDL levels can reduce the risk by 22%.
HDL for the Healthy Brain
Although any talk of cholesterol and HDL or LDL usually refers to heart health, new research has shown that HDL can also improve and protect brain health. In fact, HDL can lower your risk of Alzheimer’s disease. How? In two ways!
First of all, HDL clears beta-amyloid plaque deposits in the brain. These are the plaques that lead to brain diseases like AD and dementia. Since plaque buildup usually starts around middle age, it is important to focus on keeping HDL levels high and healthy as soon as possible. This will slow or prevent the progression of Alzheimer’s, other brain diseases, and memory loss.
Secondly, HDL protects against AD and dementia by preventing strokes. A single stroke can lead to dementia or cognitive problems. Since HDL helps prevent plaque buildup and deadly blood clots, it can act as a double defense against Alzheimer’s and other brain diseases.
Boost HDL: How?
Do your HDL and LDL numbers have room for improvement? Many turn to commonly prescribed drugs to lower LDL. Statins, the most common cholesterol-lowering drugs, can lower LDL by 18-55% (Circulation.2002; 106: 3373-3421). Unfortunately, these drugs come with many uncomfortable, often severe side effects that discourage people from continuing to take them. Also, these drugs don’t target another major factor that contributes to heart disease: low HDL levels.
What can you do to boost your HDL levels? Lifestyle changes are your frontline therapy. Consider all of the following guidelines.
- If you smoke, quit smoking. It can raise your HDL by 15-20%.
- Maintain the proper weight for your height, age, and sex to prevent obesity and accumulation of fat especially around the midsection.
- Exercise regularly and efficiently to both boost HDL and lower LDL.
- Keep a stable, normal blood sugar and blood pressure level.
- Eat a healthy, balanced diet high in vegetables, fruits, whole grains, and healthy fats such as monounsaturated fats in fish, olive oil, and avocados. This also includes omega-3 fatty acids.
- Avoid Trans fat.
- Avoid processed and refined carbohydrates because they do not have the vitamins, minerals, and fiber whole grains, vegetables, and fruits offer.
- If you decide to drink alcohol, do so in moderation.
Do these suggestions sound familiar? They are the foundation of a healthy lifestyle for your overall health. Also, these mainly dietary changes do not involve medication and their side-effects. In essence, focusing on raising your HDL is a hologram into your total level of overall health.
Are you surprised to find that a “low-cholesterol” diet is not listed in the above guidelines? It’s important to know that cholesterol comes from two places. Firstly, your liver is capable of producing cholesterol by using proteins, fats, and carbohydrates. Secondly, your body uses a very small amount of the cholesterol found in the food you eat. If you eat a lot of cholesterol, your liver will make less. If you eat little cholesterol, your liver will make more. Thus, a low-cholesterol diet will not necessarily fix your cholesterol problems.
A healthy, balanced diet rich in high-quality nutrients and antioxidants and low in refined or processed carbohydrates is much more important. This helps prevent free radicals and toxins from floating around in your blood and oxidizing and damaging LDL cholesterol. You don’t want oxidized cholesterol floating around throughout your body and to your heart and brain.
Most researchers agree that not all the functions of HDL have been discovered. As we await further understanding of the great role of HDL, it is important to focus on two goals regarding HDL:
Aim high: When it comes to your HDL levels, set a high target that is above 60 mg/dL (milligrams of cholesterol per deciliter of blood). If your HDL is between the “at risk” and “desirable” level, focus on increasing it.
Widen out: Although your LDL level can give valuable information, don’t ignore your HDL levels. If you are unsure what your HDL level is, request a blood panel that includes the most important indicator of your heart disease risk and health status. While some physicians do consider your HDL levels, most do not put enough emphasis on it due to mainstream medicine practices. Instead of extensively waiting for guidelines to be revised (if ever), request your HDL level and consider what it tells you about your health status.
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