Chapter 4-HDL - The Good Cholesterol

HDL is a type of cholesterol. HDL stands for High Density Lipoprotein. It is often referred to as the good cholesterol. There are tricks to remember this, such as let the H in HDL, stands for Healthy or High. So when one sees HDL they will hopefully remember either healthy or high and this should remind you that it is the healthy kind and we want this number to be high.



When one goes for the classic lipid profile the HDL will be reported as a number. If one's HDL is less than forty one is said to have a higher risk of heart disease. Values greater than fifty-nine are viewed as giving one a lower risk of heart disease. Values between forty and fifty-eight are a middle ground where risk could be high or low depending on other risk factors. These risk factors could be obesity, smoking, high blood pressure or being male. So if having an elevated HDL protects us from CAD the question should now become; how does one elevate HDL and what exactly is an HDL molecule?



As an extremely important side note male patients greater than forty-five years of age and especially patients male or female at or greater than fifty years of age who have any underlying medical problems absolutely need nuclear stress tests. A nuclear stress test is where a nuclear isotope is injected into the bloodstream. The patient runs on a treadmill, the heart is monitored while on the treadmill and then monitored again after the running is complete. This is an indirect assessment of potential blockages in the coronary arteries. It needs to be mentioned that even a nuclear stress test can miss coronary artery occlusions and even a negative stress test, that is, a stress test that does not reveal any blockages could be falsely negative. What this means is that there are blockages in the coronary arteries, but the nuclear stress test missed it. The only way around this is to perform cardiac catheterizations on everyone and to just stop performing nuclear stress tests since they can sometimes be misleading. I do not recommend performing cardiac catheterizations instead of stress tests as the catheterizations are invasive and have higher complications associated with their performance. Getting a nuclear stress is still the preferred way to indirectly assess for the presence of coronary artery disease. If the stress test is positive then one will need a cardiac catheterization.



Before I leave this side-note, if you are someone with diabetes and you are a male or female at or greater than fifty years of age you absolutely need a nuclear stress test. This is because diabetics are notorious for having what is known as silent heart attacks and even blockages, which cause no symptoms whatsoever. You could be walking around with significant CAD and not even know it. And the only chance of knowing this is through a nuclear stress test. I cannot tell you how many times a diabetic patient over the age of fifty has come to see me for a regular check-up, has had no symptoms of chest pain, difficulty in breathing, or any other symptom which might have alerted me to the existence of coronary artery occlusion; has had normal looking EKGs and I perform a nuclear stress test and find significant coronary artery blockages. The scary thing is that some of these patients had actually been seeing other docs, including cardiologists, who failed to perform a routine nuclear stress test. The bottom line is that if you have diabetes, or any other medical issue and you are at or greater than the age of fifty, you need a nuclear stress test. If you cannot walk for whatever reason there are other nuclear stress tests which can be performed to help assess for the presence of CAD. And lastly, if you are male or female at or greater than the age of sixty-YOU ABSOLUTELY NEED A NUCLEAR STRESS TEST NO MATTER WHAT!!!! This is because as we get older we can accrue plaques in our coronary arteries just from being on the planet longer. Now, let us get back to our discussion as to what an HDL molecule is made up of.



First, we will look at what comprises an HDL molecule. Well, HDL stands for high-density lipoprotein. So, it has to have some protein in it, lipo means fat, so fats there too, and it is high density; but, still, what does that mean. It simply means it is a molecule, which contains cholesterol, fat, and protein. Since there is a lower amount of fat in an HDL molecule it is called high density because fat is less dense than protein and cholesterol. The more fat the lower the density, the less fat the higher the density.



OK, now here is something very interesting. Ask your typical internist, family doc, pediatrician, cardiologist, or just about anyone who thinks they know something about HDL how to increase the HDL in the bloodstream. We all see low HDLs and we see them a lot. Usually in men, but also in women. The answer they give is almost always the same; if you want to increase your HDL, lower your fat and cholesterol intake and increase your whole grains, fruits and vegetables. This, the above docs say, will increase your HDL.



From our discussion thus far you know immediately your body will have all the things necessary to make more fat and cholesterol. But what kind of fat and cholesterol will we make? The fat part is easy; we will make more triglycerides (you know what, I am getting tired of spelling out triglycerides so for now on I am calling them TGs). As far as cholesterol is concerned, again, what kind of cholesterol will we make when we eat a diet low in fat and cholesterol?



Well, cholesterol is cholesterol is cholesterol, so the short answer is; just plain ole cholesterol is formed. But is it HDL, LDL, VLDL or IDL, which I will now call the DLs? Guess what, if you focus on those three letter cholesterols you start to forget that they are simply carrier molecules of cholesterol. That is correct, all these DLs do is carry cholesterol around in the body and exchange it with other DLs. So viewing cholesterol as a good or bad type of cholesterol totally confuses the picture.



Another side note: HDL is known for carrying away cholesterol after a cell dies. After the HDL molecule picks this cholesterol up it shuttles it away and gives it to other DLs. But why is it considered the good cholesterol? Well, that is because HDL is also known to take cholesterol back to the liver for its removal from the bloodstream



Now the confusing part begins. Exactly how do our bodies actually get rid of cholesterol? There are certain medications that are referred to as bile acid sequestrants. Bile is a substance the liver makes, it gets stored in the gallbladder and is released to help with the digestion of fats and cholesterol. Bile acid itself contains cholesterol so the drug companies developed a medication which binds with these bile acids, does not let them go and when you poop out comes the cholesterol. Pretty clever.



Only thing is these specific types of meds can only lower the cholesterol number by a small amount. Anyone with a high cholesterol number will need another med, assuming the proper diet is not revealed to the patient to help lower the cholesterol number further. It may appear as if we have come off our topic of HDL, but we really have not.



You would think that if HDL was a good cholesterol it would somehow get rid of the cholesterol from the body so it could not bind to our arteries and kill us. But this does not happen. HDL quickly takes and gives its cholesterol to other DLs. One of which is the LDL transporter, which everyone mistakenly believes is the bad cholesterol. But if HDL is quickly giving its cholesterol to LDL, I am still confused. Would that not make HDL a bad cholesterol too, since it is aiding and abetting the LDL cholesterol? I will discuss more about LDL cholesterol below, but for now understand that LDL is considered the bad cholesterol.



OK, so let us get back to our typical internist, family doc, pediatrician, or cardiologist. When we ask them how to raise the HDL they will answer exercise, follow a low fat, low cholesterol diet, which means we need to eat more whole grains, fruits and veggies. After sixteen years of practicing medicine I can tell you that this does not work. Some docs will be thinking that, "Of course it works." And my reply is that in sixteen years of caring for patients I have rarely seen this diet/exercise approach work to significantly elevate the HDL.



Well what have I seen work you might ask? The only thing I have seen work to substantially increase HDL, doubling it, sometimes increasing the HDL by two and a half times its value; is increasing one's consumption of fat and cholesterol, coupled with a dramatic lowering of one's carb intake.



That is correct, as crazy as it sounds: increasing one's consumption of fat and cholesterol in the diet will substantially raise your HDL values. This process can take up to a year, but it works and it works every time. Every time! When patients of mine increase their fat and cholesterol consumption their HDLs oftentimes double. That's right, double! The best the drug companies can offer is somewhere around a thirty-five percent increase in HDL, but if one increases their consumption of fats and cholesterol and lowers their carb intake, one can increase the HDL by 100%.



To put this in perspective, a thirty-five percent increase means that if your HDL is thirty, not an unusual number to see, the most you can expect as an increase if you are using meds will be from thirty to forty. Sounds impressive until you realize that you are still at increased risk of heart disease even with an HDL in the forty range. How about we take that HDL of thirty and change it into a sixty or seventy, this can be done if you follow the correct diet.



I really am not sure why the HDL doubles. I have read the books, but cannot figure it out. Only thing I can come up with is since the body is not making as much cholesterol, it chooses to make HDL and the good LDL preferentially over the others. So now one may wonder, what happens to the LDL thing, you know, that thing we doctors mistakenly call the bad cholesterol. I will show you in Chapter Six. Before we can talk intelligently about LDL we need to discuss some basic math and I mean really basic math, that is, the math used to calculate all the typical LDLs in our country.



"Nothing is more difficult than competing with a myth"