Cholesterol - the good and the bad
Total cholesterol is not an extremely good predictor of heart disease risk because it does not distinguish between the good and bad cholesterol.
Although it is true that segments of the population with higher cholesterol level tend to have higher cardiovascular risk. The difference in risk of someone with high cholesterol with someone with low cholesterol is relatively small. A person with normal cholesterol can have heart attack, just as there are people with high cholesterol that do not have heart attacks. Dr. Barry Sears say that half the people hospitalized for heart attack had normal cholesterol levels.[7]
To more accurately access the risk, we have to look at a more detailed measures of the cholesterol profile than just "total cholesterol". As you probably heard, there are "good cholesterol" and "bad cholesterol".
These are just simplified terms used for less verbose communication. But really, cholesterol is just cholesterol. Cholesterol is a waxy lipid that is found in all cell membranes. It is essential for keeping the integrity of the cell membrane healthy.
Book: "The Great Cholesterol Myth"
What Makes Cholesterol Good or Bad
What makes cholesterol good or bad is how they are packaged. In order for cholesterol to be transported through the circulatory system, it has to be packaged in a protein surrounding shell. This shell can either be a high-density lipoprotein (HDL) or low-density lipoprotein (LDL). The former HDL is what the public knows as "good cholesterol". The latter LDL is what is known as "bad cholesterol".
When we say "HDL cholesterol" is good, we are saying that the packaging form of the "high density lipoprotien" is good. When we say "LDL cholesterol" is bad we are saying the "low-density lipoprotein" way of packaging cholesterol is bad.
Shane Ellison says that "Cholesterol is Not the Problem"
Cholesterol is So Essential that Most Cells and the Liver Produces It
Cholesterol play an important role in helping to[5] ...
- build cell walls and keep them flexible so that they function better
- insulate neurons and need for proper function of serotonin receptors in the brain.
- synthesize hormone
- produce bile
- be a precursor of vitamin D
Cholesterol can act as an antioxidant which protects us from cancer and free-radical damage.
Cholesterol is so essential that our liver makes cholesterol for us. And mother's breast milk is very high in cholesterol since a growing baby needs it for development.
Cholesterol is measured in milligrams per deciliter with 200 mg/dL of "total cholesterol" as being the arbitrary cutoff for being high cholesterol. A person with a cholesterol of 200 mg/dL would have 10,000 mg of cholesterol circulating in their blood (assuming a total blood volume of 5 liters). Most of this cholesterol was produced by the liver. One egg contains roughly 200 mg of cholesterol. So how much is consuming one egg is going to have an effect on your cholesterol level? Not much.
Cholesterol does not cause arteriosclerosis
That is what the book The Heart Revolution says on page 14 ...
"... the cholesterol does not cause the arteriosclerosis"
High cholesterol may be associated with an increase risk of arteriosclerosis, but not a cause. That is because cholesterol is marker of a disease process; cholesterol is a symptom.
The real cause of arteriosclerosis is high homocysteine levels which causes plaques to form on arteries. This was shown in animal studies when they injected homocysteine in their blood. Homocysteine damages the arterial lining. Hence it may be just as important to check homocysteine as it is to check your cholesterol.
Cholesterol is dispatched to the help patch up the damaged arterial wall. Blaming cholesterol for the damage is like blaming the police at a crime scene.
You have heard that LDL is "bad cholesterol". LDL is a lipoprotein that carries cholesterol. But another thing that LDL lipoprotein carries is homocysteine.
What causes high homocysteine? It is B vitamin deficiency. Either we are not eating enough food with B vitamins or that we are eating too much processed foods that are devoid of B vitamins.
Furthermore, the book writes ...
"... the less cholesterol we eat in the diet, the more cholesterol is made in the body. Therefore, if you restrict the amount of cholesterol you eat, your body will simply produce more." [page 19]
A person's cholesterol level and cholesterol profile has more to do with the person's liver production of cholesterol rather than cholesterol consumption. In fact,
Chris Kresser, says in the video on the right...
"Cholesterol in the diet does not raises cholesterol in the blood for most people. And even when it does, it raises the large buoyant LDL which we know is not a risk factor for heart disease."
Most of the cholesterol in our blood is not from consuming cholesterol from foods, but from generation of cholesterol by our liver. How much cholesterol our liver generates is determined by many other factors.
Cholesterol for Brain Health
Twenty-five percent of our body's cholesterol is found in the brain, even though the brain is 2% of body mass. That implies that cholesterol is very important for brain function and it is. People with extremely low cholesterol have higher risk of depression and suicides.
Dr. Emily Deans says cholesterol is good for the the brain. That is not to say that eating cholesterol will give more cholesterol to the brain. Most of the cholesterol in the brain is manufactured in the brain. But it does suggest that cholesterol is not as bad as we think.
Stephanie Seneff writes that ..
"Cholesterol is essential both in transmitting nerve signals and in fighting off infections."
She says that the brains of Alzheimer's patient are severely deficient in cholesterol and healthy fats, which may have been partially caused by low-fat diets.
Chris Masterjohn writes that ...
"A 1995 human study found that feeding eggs as a source of dietary cholesterol was helpful to elderly whose memory was impaired"
And that cholesterol secreted by glial cells in the brain is involved in synapse formation. Cholesterol was the limiting factor as to how much synapse can form.
Cholesterol Studies
In the video on the right, registered dietitian Annette Presley looked at the various fat and cholesterol diet studies. She explains the why there is little evidence that implicates saturated fat and cholesterol with heart disease. Studies can have confounding factors. Some studies have multiple dietary intervention so that we can not say which intervention was responsible. Animal models may not behave like humans. For example, dogs can consume a lot of cholesterol without effect; while rabbits being herbivores have a large effect. Earlier studies also even lumped trans fat (which we know is bad) with the saturated fat category.
She also explains why it is the oxidized LDL cholesterol that is contributing to heart disease. And the polyunsaturated fats of vegetable oils and margarine that are the ones that get oxidized quickly. The saturated fats of butter is slowest to get oxidized. That is why she also believes that butter is healthier than margarine.
The book Nourishing Traditions writes ...
"High serum cholesterol levels often indicates that the body needs cholesterol to protect itself from high levels of altered, free radical-containing fat." [page 13]
Cholesterol helps patch damages in arteries. Like a fireman that is always at the scene of a fire, cholesterol is there to help and is not the culprit to heart disease.
One study showed that excessive omega-3 fish oil can result in increased LDL levels and insulin resistance in those with metabolic syndrome.
High HDL is good
It is clear that you want more of the HDL cholesterol. They are the packages the brings the excess cholesterol from the cells back to the liver for processing or recycling. A better measure than looking just at "total cholesterol" is to look at the ratio between the good cholesterol over total cholesterol. You want to make sure good HDL cholesterol is high.
Others look at the ratio between the good HDL and bad LDL cholesterol. When people say they have good cholesterol profile, they usually mean a high HDL in relation to low LDL numbers.
Different Types of LDL
LDL are the packages of cholesterol that sent from the liver to the cells. It is called bad cholesterol because it is these cholesterol that sticks to the arterial walls to form plaque. However, it has been suggested that LDL cholesterol sticks on the arterial wall only when there is inflammation of the walls. When there is some arterial inflammation, LDL increases because the body is trying to send cholesterol there to repair it.
The story of LDL is a bit more complicated. In general, we want LDL to be low. But more importantly there are two different types of LDL. Looking at LDL "bad" cholesterol by itself is not enough. You have to look at the type of LDL. Dr. Dwight Lundell says it is inflammation that causes heart disease. And that without inflammation, cholesterol would not stick to the arteries. [reference]
There is the small dense version of LDL known as "pattern B". This is the bad kind because they are small enough to get in between the arterial cells and form plaque. And then there is large buoyant fluffy version of LDL known as pattern A. This type of LDL does not stick to arterial walls and are not a risk factor for heart disease. The VAP Test is one of the ways to determine if your LDL cholesterol is pattern A or B.
Most people have a mixture of pattern A and B. People with pattern B LDL have 4 times the cardiovascular risk as people with predominately pattern A.[3]
The book Fat Chance by Dr. Robert Lustig writes ...
"there are two types of LDLs: one is called large buoyant LDL, or type A LDL, and the other is called small dense LDL, or type B LDL. Large buoyant LDL floats in the bloodstream. It's too big to get underneath the cells lining your blood vessels to start the atherosclerotic (artery wall thickening) process." [page 113]
LDL particle number is what matters
Some say that more important than even particle size is the number of LDL particles. It is the number of particles crashing into your artery walls that determines your risk. The higher the number of particles of LDL, the greater the risk.
Dr. Michael Richman writes on WebMD that ...
"Atherosclerosis results from a buildup of cholesterol-laden macrophages in the arterial intima. This occurs when atherogenic lipoprotein particles (principally low-density lipoprotein [LDL]) enter the arterial wall, become oxidized, and are subsequently ingested by macrophages."
He writes that the LDL-P test will tell you the number of LDL particles which is more important than the standard LDL-C test which tell you the amount of cholesterol. Or you can do the ApoB test which counts the number of VLDL and LDL particles. About 90 to 95% of the ApoB particles will be LDL-P particles.
Chris Kresser mentions in his podcast ...
"... it’s not really even controversial at this point in the scientific literature that LDL particle number is much more predictive of heart disease."
Total Cholesterol over HDL
Once you know the particle number, then knowing the size does not provide any additional information. In another podcast, Kresser talks more about how if you don't have access to these fancy cholesterol tests, the standard tests and other measures can still give you a pretty good idea of heart attack risk. He says ...
"I still think LDL particle number is a better lipid marker than LDL or total cholesterol or even the total/HDL cholesterol ratio, but total/HDL ratio for most people is a good surrogate for LDL particle number, and if you can’t afford to get or don’t have access to ApoB or LDL particle number, that can be a good substitute for many people."
where "total/HDL" is the ratio of total cholesterol over HDL cholesterol and that should be less than 4 and ideally be less than 3.
That is why some people look to the cholesterol ratio as defined by total cholesterol / HDL, with a ratio of 3.5 or lower being optimal (according to WebMd article linked here)
Triglycerides / HDL ratio as a good predictor
If you don't have access to LDL-P or ApoB test, then look to triglycerides as a clue. Triglycerides will give you a better measure of risk than total cholesterol.
Some people like to look at the triglycerides/HDL ratio -- close to 1 is good and high number like 3 is bad.
Watch Out For the Atherogenic Lipid Triad
If total cholesterol is not that important, then what measures should we look at?
The danger signs to watch out for are ...
- Type B (small dense type) pattern of LDL
- High Triglycerides
- Low levels of HDL
Some call these three measures the "atherogenic lipid triad".
When triglycerides are high, it tends to be that a larger portion of the LDL particles are the dangerous small dense types.
What Diet Causes High LDL
Dr. Dayspring of LecturePad.org explains that when you eat carbs and fructose, you get a fatty liver. When the liver starts getting fat, it pumps out more number of VLDL particles and more triglycerides in these VLDL. Greater number of VLDL particles gives rises to greater number of LDL particles.
Cardiologist Dr. William Davis says that ...
"small LDL particles are, by far and away, the #1 cause for heart disease. ... Small LDL is largely the province of people who consume carbohydrates"[4]
That is why it is possible for vegetarians to have high cholesterol, even though cholesterol is not found in plant foods. The body is making its own cholesterol.
As a vegetarian for 26-year, John Nicholson wrote the book The Meat Fix: How a Lifetime of Healthy Living Nearly Killed Me! in which he tells his story of how vegetarianism made him obese, had high cholesterol, and IBS. He lost weigh and regained his health after adding back animal products.
Chris Masterjohn explains at the Ancestral Health Symposium that it is the oxidation of the LDL cholesterol that becomes a problem to heart disease.
LDL will have increased oxidation when it is in the blood stream for a longer duration due to the backed up of the cell's LDL receptors to uptake the LDL into the cells.
It also depends on the antioxidation capability of the body.
Masterjohn also presented another good explanation in his interview with Dr. Mercola (video on the right).
Dr. Nicholas Perricone writes that ...
"Vitamin C ... may be protective against the oxidation of LDL, since low vitamin C levels in the aorta have been found in people with cardiovascular disease. Together, beta-carotene and vitamin C may offer synergistic protection against cardiovascular disease. In addition, both of these antioxidants complement the actions of vitamin E in preventing oxidation of LDL and other biomolecules." [page 137 of Forever Young]
There are some controversy about what diets causes a rise in cholesterol. Some say it is carbohydrates. Other such as medicinenet.com says it is saturated fats and cholesterol ...
"Diets that are high in saturated fats and cholesterol decrease the LDL receptor activity in the liver, thereby raising the levels of LDL cholesterol in the blood ... trials have consistently and conclusively shown that lowering LDL cholesterol reduces the risk of heart attacks and strokes and prolongs life. These trials have further shown that the benefits of lowering cholesterol outweigh the risks of side effects of the statin medications. ... In order to lower LDL cholesterol, the activity level of the LDL receptors must be increased. LDL receptor activities can be increased by diets that are low in cholesterol and saturated fats and by medications."[1]
Watch Sally Fallon-Morell present the research of Marg Enig PhD in a presentation titled "The Oiling of America" which explains why cholesterol and saturated fats do not cause heart disease. It debunks some of the studies that shows otherwise, including Ancel Keys "Seven Country Study". The presentation suggests that high cholesterol not a significant risk factor for women. And it is only a risk factor for men if their cholesterol is significantly high.
However, very high or very low cholesterol may be an marker of something else wrong going on and that it needs further examination by a health professional.
Lipoprotein(a)
Lipoprotein(a) is a lipoprotein subclass that is another marker of risk of heart disease. This value varies greatly among individuals and the reference range depends on many factors including age, etc.
The book Primal Body, Primal Mind writes that of all the lipoproteins, it is the measure of the lipoprotein(a) that is of the most relevant to heart disease. This is because lipoprotein(a) is smaller and denser than the others LDL and can lodge itself in between vascular arterial cells and trigger inflammatory response.
You want your lipoprotein(a) to be low. And statin drugs can not lower it. Only diet can. The book writes ...
"It is high-carbohydrate diets and the presence of excess insulin that are responsible for the production of this undesirable lipoprotein." [page 81]
Trans fat in the diet also raises lipoprotein(a) and should be avoided as much as possible.
A bit of cholesterol chemistry
Cholesterol is a molecule with 74 atoms -- quite a large one, considering that water has only 3 atoms. Cholesterol consists of 27 carbon atoms, 46 hydrogen atoms, and one oxygen with a molecular formula is C27H46O.
However, the formula can be equivalently written as C27H45OH. This makes it more apparent that it contain an hydroxyl (OH) group at one polar end of the molecule making that end soluable in water. The rest of the molecule is fat soluable. Overall, the molecular is not soluable enough in water to travel through it on its own and therefore must be transported through the bloodstream contain within lipoproteins.
Beside the hydroxyl group, the molecule has a hydrocarbon tail and and a structure with 4 hydrocarbon rings.
To learn more about cholesterol chemistry, Chris Masterjohn has a good series of articles.
For an advanced lecture (at the clinical level) on cholesterol, watch Dr. Robert Maki's lecture on Hawthorn University webinar.
Factors that can influence cholesterol
LiveStrong says that ...
"Cholesterol levels tend to stay fairly constant from day to day due to the complex mechanisms that control the levels in your blood."
and
"Cholesterol levels remain fairly constant during the day."
However, cholesterol tend to go up slightly in winter.[reference]
CNN reports that high dose fish oil lowers triglycerides, but not LDL (may even increases it slightly).
Olive oil lowers cholesterol.
High cholesterol may be a sign of inflammation. Some people with gluten sensitivity who continues to consume gluten may have inflammation in the gut that causes high cholesterol.
Paul Jaminet writes that ...
"Cholesterol and LDL particles are part of the vascular wound repair process. Very high LDL levels are a marker of widespread vascular injury."
If you want to learn more about cholesterol and why statins may not be so good, watch the following documentary by Catalyst...
Note:
Article written May 2012 is only opinion at time of writing. Author is not a medical professional and this is not medical advice.
References:
- [1] In-depth information on cholesterol on MedicineNet.com
Cholesterol information in-depth, mechanisms and mechanics of cholesterol plaque. - [2] Cholesterol test - MayoClinic.com
Cholesterol test — Overview covers how to interpret the results of this common blood test. - [3] Atherotech Diagnostics Lab. The VAP Cholesterol Test. Your Heart Partner
Atherotech - The new breakthrough VAP cholesterol test provides the missing information that identifies people who go undetected with the traditional cholesterol test. In fact, the VAP Test identifies up to twice as many people at risk including thos - [4] Why small LDL particles are the #1 cause of heart disease in the US | Track Your Plaque Blog
- [5] Role of Cholesterol
- [7] Zone Diet | Home of Anti-Inflammatory Nutrition