Low Density Lipoprotein

Lipoprotein particles are proteins that encapsulate lipids like cholesterol and triglycerides to transport them in the bloodstream. The more the lipids, the lower the density of the lipoproteins. Low Density or LDL particles can deposit themselves on the wall of the arteries to form plaque and overtime build up to cause atherosclerosis. If a piece of plaque drops from the artery wall, an acute problem arises where the clot can obstruct a blood vessel causing stroke or heart attack.

Out of convenience and pricewise, lipid profile bloodtests measure the cholesterol inside the lipoproteins to estimate the amount of LDL and HDL in your bloodstream.

Since LDL can cause plaque, atherosclerosis, stroke and heart attack, the cholesterol measured in the LDL particles get the connotation as being "bad cholesterol".

However, cholesterol is essential for the proper function of your body, it’s the LDL that contributes to the risk factor of getting cardio vascular disease.

What are lipoproteins

The word lipoprotein consists of 2 words:

• lipo (as in liposuction) stands for fat and
• protein.

When proteins encapsulate lipids, they are called lipoproteins.

Why do the proteins encapsulate the lipids? That is because our bodies can’t dissolve lipid in water nor in the bloodstream. In order to transport lipids through the bloodstream, they need to get encapsulated by proteins. Kind of comparing with oil and water that shift, unless you add proteins of an egg and manage to make a vinaigrette.

To simplify it: in the human world, humans are transported by carriers like cars, busses, trains, ships… In the cell world, lipids are transported by the lipoprotein carriers.

Density: how more heavy are lipoproteins compared to water?

LDL is the abbreviation of Low Density Lipoprotein and HDL stands for High Density Lipoprotein. Lets recap some elementary physics:

The fact that oil floats on the surface of water and doesn’t sink to the bottom, is because the density of the oil is lower compared to water:

• Water weighs 1 gram per 1 milliliter, so it’s density is 1g/ml.
• Olive oils for example have a density between 0.8 and 0.92 g/ml, lower than water that is
• Proteins normally have a density above 1.3 g/ml.

Since lipoproteins are made up both of lipids and proteins, their density depends on the ratio proteins/lipids:

• The more the lipids, the lighter the lipoprotein, hence the lower its density.
• The more the proteins, the heavier the lipoprotein and the higher its density.

As such the classification for all 5 lipoproteins from low to high density:

• Chylomicrons: less than 0.95 g/ml (originate in your intestines after a meal and transport dietary cholesterol and fat through the lymphatic system)
• VLDL: very low density lipoprotein , between 0.95 g/ml and 1.006 g/ml (produced by your liver, they are the predominant carriers of circulating triglycerides, used to supply free fatty acids to your tissues)
• LDL: low density lipoprotein , between 1.006 g/ml and 1.062 g/ml (byproducts during VLDL metabolism and the primary carriers for cholesterol in the bloodstream to where they are needed)
• HDL: high density lipoprotein, between 1.062 g/ml and 1.20 g/ml (carry excess cholesterol to the liver)
• VHDL: very high density lipoprotein , more than 1.20 g/ml

Classification of lipoproteins according to density from low to high: chylomicrons, VLDL, LDL, HDL, VHDL (picture courtesy of medscape.com)

What is bad cholesterol: isn’t cholesterol essential for every living cell?

Cholesterol is a fat or lipid that can be found in each cell of your body. Its first and foremost function is to make sure the cell membranes:

• don’t become to fluid (so the cells don’t leak out nor get penetrated by the fluid around them)
• don’t become to firm (so the cells can still exchange molecules with other cells).

Apart from being an essential component of the membranes of any of your cells, it’s used to form the bile acids that are stored in your gall bladder and helps your intestine absorbing fats.

Last but not least. cholesterol is needed to make hormones (such as testosterone for males and estrogen for females) and Vitamine D. (as mentioned in The Harvard Medical School Guide to Lowering Your Cholesterol)

Although cholesterol is essential to keep you and your cells healthy, the name-confusion starts by labeling the cholesterol carriers as being real cholesterol:

• HDL carriers get called "good cholesterol"
• LDL carriers get called "bad cholesterol"

Now what is bad about transporting cholesterol around in your bloodstream to where cells need it? Nothing really! So what makes LDL having a connotation as "bad cholesterol"?

The LDL carrier (hence NOT cholesterol by itself) has a tendency to deposit itself with fat, calcium and other substances at the wall of your blood vessels under the general term of "plaque". When too much plaque on your arteries becomes problematic, it is called atherosclerosis: a condition that can further cause strokes (not enough blood flow to the brain) and heart attacks.

Atherosclerosis or narrowing of the arteries due to plaque deposits (picture courtesy of National Heart Lung and Blood Institute)

Don’t confuse atherosclerosis with arteriosclerosis: the hardening of the arteries over time that makes the walls of your blood vessels stiff, thick and therefore less flexible.

A stroke caused by a brain artery clogged by either a piece of atherosclerotic plaque that broke away or a blood clot. (picture courtesy of MedlinePlus)

An acute and dangerous problem occurs when a clot of plaque drops down from the bloodvessel and starts floating around in the blood. Once this clot enters thinner capillaries or bloodvessels narrowed by atherosclerosis, it can temporary or permanently block the bloodflow. A permanent blockage leads to the death of the previously supplied tissues that lay ahead. A blockage in the brain is called a stroke.

Good and bad cholesterol levels

In stead of accurately measuring the real amount of LDL in your blood, bloodtests measure the cholesterol encapsulated in the LDL and HDL. Why? Because it’s easier and cheaper to measure the cholesterol from the lipoproteins and make a calculated estimation in stead of measuring the lipoproteins themselves. Hence the connotation of LDL cholesterol becoming "bad cholesterol". However an excessive amount of LDL is one of the risk factors of cardio vascular disease.

Medical practice recommends people to keep their LDL-cholesterol within "normal levels". Do know that high levels of LDL cholesterol is only an indication of one of the risk factors of cardio vascular disease. There is no guarantee that people with low LDL-cholesterol will be totally free from heart attacks: heart attacks remain to be unpredictable.

Normal LDL cholesterol levels : "Normal" is simply what is statistically measured in certain groups of people. Here the "groups" are divided according to their cardio vascular health.

According to the Mayo Clinic, the American Heart Association and the US National Heart, Lung and Blood Institute (NHLBI), borderline high cholesterol levels start in the US from 130 mg/dL. For Europe and Canada measuring in mmol/L: borderline high cholesterol levels start from 3.4mmol/L.

• Below 70 mg/dL (1.8 mmol/L) : Optimal LDL cholesterol level for people with a very high risk of heart disease
• Below 100 mg/dL (2.6 mmol/L) : Optimal LDL cholesterol level for people with a risk of heart disease
• From 100 to 129 mg/dL (2.6-3.3 mmol/L) : Near ideal LDL cholesterol levels
• From 130-159 mg/dL (3.4-4.1 mmol/L) : Borderline high LDL cholesterol levels
• From 160-189 mg/dL (4.1-4.9 mmol/L) : High LDL cholesterol levels
• From 190 mg/dL (4.9 mmol/L) onwards : Very high LDL cholesterol levels

If you want to calculate for yourself how high your risk for heart disease is, you could do the calculations mentioned at What Is Your Risk of Developing Heart Disease or Having a Heart Attack? and Estimate of 10-Year Risk for Coronary Heart Disease. The idea is to first look at your overall health and then your cholesterol levels. Before you head over to those websites and get lost in mathematics, read the next sentence first:

The calculation method clearly states that it should also start taking into consideration a persons physical activities and bodyweight. Overweight and not physically active people have a higher risk towards heart diseases: hence there should be 8 risk factors to consider.

The only 5 risk factors used in the calculation, mention an increased risk of heart diseases when you:

1. are a smoker
2. have a high blood pressure (more than 140/90 mmHg) or are on high blood pressure medication
3. have less than 40 mg/dL (1 mmol/L) HDL
4. are :above 45 years old for men, or above 55 years old for women
5. have parents, brothers or sister that suffer from an early heart disease (early means: for men before 55, for women before 65)

If your HDL cholesterol is above 60 mg/dL (1.55 mmol/L), you can minus 1 from your 5 risk factors count. When after this possible subtraction, you scored 2 or more: you can find your more accurate heart disease risk score that also takes your cholesterol levels into account.

The Mayo Clinic adds even 2 more risk factors:

• diabetes
• Elevated lipoprotein (a), another type of fat (lipid) in your blood

Cholesterol ratio

According to Thomas Behrenbeck, M.D., Ph.D from the Mayo Clinic, ratio’s aren’t that important. To actively reduce your risk for heart disease, it is important to know the real numbers of your total cholesterol, your LDL cholesterol and your HDL cholesterol. Why real numbers and not ratios? Reason given is the existence of LDL lowering drugs that are proven to lower your risk of heart disease.

According to the American Heart Association, the ratio that you find on your bloodtest results should be below 5 to 1 and optimally below 3.5 to 1. This ratio is calculated by dividing your total cholesterol (HDL + LDL) with your HDL cholesterol.

However, we just mentioned above that if your HDL is above 60 mg/dL (1.55 mmol/L), your overal risk factor decreases significantly. This explains why according to health advocate Mike Adams the ratio LDL/HDL is equally important to measure your risk status. According to Mike, the risk for people having a possible heart attack:

• LDL/HDL ratio 10 and above: very high risk
• LDL/HDL ratios measuring between 7.1 and 10: high risk
• LDL/HDL ratios measuring between 4.4 and 7.1: medium risk
• LDL/HDL ratios measuring between 3.3 and 4.4: low risk

The importance of LDL/HDL ratio makes logical sense, since the more HDL you have, the more LDL will be transported back to the liver, hence won’t be actively building up plaque in your arteries.

I do notice that as far as I know, there are no FDA approved drugs that increase good HDL. As stated in the risk factor calculation, the existing industry that manufactures LDL lowering drugs is fully aware of the importance of a high HDL and of Mike Adams’ LDL/HDL ratio.

This LDL lowering drugs industry has commercially no benefit in using the ratio, since they can only lower the LDL part of the ratio. Foodsupplements like Cholest-Natural from Xtendlife however may help to both lower your LDL and increase your HDL, so ratio’s do become commercially attractive.

Why do you need to lower your LDL cholesterol?

Lowering your LDL cholesterol is just one of the contributing factors that could help reduce your risk of heart disease. Your ultimate goal is to stay healthy and not blindly focus on only LDL-cholesterol levels.

If your overall risk factors are all low, and your LDL cholesterol levels are high, a wise GP could advise against taking statins longterm: because the price and the possible side effect would outweigh the possible benefits.

If your overal risks indicate that you need to lower your LDL cholesterol, the 2 most mentioned paths to follow are taking cholesterol lowering drugs and diet. For the drugs, the most known is atorvastatin: a statin better known under the brandname Lipitor by Pfizer. For the diet there is still no consensus to what you should do.

When it comes to drugs, we tend to listen to doctors and pharmaceutical research reports and don’t engage in discussing the consensus.

Which cholesterol diet to follow?

When it comes to diet, some people like food writer Christine France in her book "The Low Cholesterol Diet & Recipe Book" say that the cholesterol in food doesn’t have a major effect on the amount of blood cholesterol in most people.

Others say that the main cause for blood cholesterol going up is because you eat too much fat, especially saturated and trans fats. The Mayo Clinic stresses that you need to reduce your daily intake of cholesterol AND total fats, especially:

• reduce saturated fats (consumed e.g. in meat, full fat dairy items and some oils). Saturated fats raise your cholesterol
• reduce trans fats (consumed e.g. in long shelf life cakes and cookies and some margarines). Trans fats not only raise your bad LDL but at the same time lower your good HDL!

A rule of thumb to recognize saturated and trans fats according to the Mayo Clinic is that fats rich in saturated or trans fats tend to be solid at room temperature. Examples now are easy to come up with: ghee, butter, shortening, the untrimmed fat around a steak and lard… to name a few. Do know that liquid oils contain a mixture of saturated and unsaturated fast.

According to The Harvard Medical School Guide to Lowering Your Cholesterol, the amount of saturated fat AND cholesterol you eat will relate to the amount of LDL-cholesterol measured in your blood.

To lower your LDL cholesterol, a reduced fat diet should work for most people. Do note the words reduced fat and not simply low fat. According to author Mason W. Freeman, most low fat diets lower both your good (HDL) and bad (LDL) cholesterol. So he insists that you need to incorporate good fats in your diet and reduce bad fats and total fat.

The so called "good fats", although being fats, do decrease your LDL cholesterol. Good fats include: monounsaturated fats, omega-3 polyunsaturated fats and omega-6 polyunsaturated fats. Stearic acid, although being a saturated fat, found in pure chocolate also decreases LDL levels.

The polyunsaturated fats are the healthiest, are essential for your body to function and can’t be metabolized by your body. All these explain why a lot of health nutritionists recommend you to include fish in your diet. The Mayo Clinic especially stresses the benefits of fats from nuts and fish:

• Nuts: walnuts and almonds are rich in polyunsaturated fats. Unsalted or uncoated almonds, peanuts, pine nuts, pistachio nuts, walnuts and hazelnuts: eat about 42 grams or 1.5 oz a day. Don’t eat too much nuts either because you could start gaining weight, unless you make wise decisions and change food items rich in saturated fats like cheese and meat with nuts.
• Fish: The American Hearth Association recommends 2 servings of fish a week. Raw or grilled, in order not to add unhealthy fats during frying. The most omega 3 fatty acids are found in Albacore tuna, halibut, herring, lake trout, mackerel, salmon and sardines.

The National Cholesterol Education Program (NCEP), launched by the National Heart, Lung, and Blood Institute (NHLBI), recommends to initiate the following Therapeutic Lifestyle Changes (TLC) if you want to lower your LDL:

• daily cholesterol intake should be less than 200 mg/day
• daily calories from saturated fat intake should be less than 7% of your total daily calorie intake. To calculate: 1 gram fat contains 9 kCal. For instance: if your general recommended kCal intake is 2000, then your saturated fat calories should be less than 7% of 2000 = 140 kCal. Divided by 9kCal results that you shouldn’t be eating more than 15.55 gram saturated fat.
• eat more soluble fiber (viscous fiber), between 10-25 g/day. None of the fibers can be digested. Soluble fiber turns water into a gel like substance. According to the Mayo Clinic it can be found in oats, barley, beans and peas, psyllium, carrots, and fruits like bananas, prunes and pears: 1 1/2 cup cooked oatmeal with banana = about 10 grams of soluble fiber.
• eat food fortified with plant stanols and plant sterols (at least 2g plant stanols of sterols/day to be effective) . The Mayo Clinic gives this example: about 4 fluid ounce or about 470 ml of fortified orange juice will give you the minimum of 2 grams. However, if you eat fortified margarine, do know that the extra amount of saturated and transfat intake could outweigh the benefits of the sterols and stanols. (Plant sterols are isolated from soy bean and pine tree oils. The food supplement Cholest-Natural from Xtendlife mentioned below contains the plant sterol Beta-sitosterol from soy bean extract)
• manage your weight
• increase your physical activities.

Natural remedies for cholesterol

The most natural remedy to lower your cholesterol is changing your lifestyle. For those who have tried that and don’t see any changes in their next lipid profile bloodtest, they need to make sure they tried "all" before attempting statin drugs.

For my first attempt (Februari 2012) to lower my cholesterol, I changed my breakfast to oats and drank lots of green tea: both known to be "superfoods" that lower cholesterol. 6 months later, my LDL was higher than before.

Obviously I didn’t try "all" possible lifestyle changes. My oat breakfast contained lots of full cream milk, I continued cooking with butter and cream and I am still as inactive as before.

My second attempt (September 2012) is to lower my daily dietary cholesterol intake to less than 200 mg/ day and see how that influences my LDL cholesterol levels. If still no changes in a next bloodtest, I will follow a reduced fat diet whilst increasing the good fats. If that doesn’t work, I have no choice but to start doing exercise 🙂

If that still wouldn’t work, I will try the natural food supplement Cholest Natural from Xtendlife, that attempts to lower cholesterol in 6 ways. Of course you could try supplements that only tackle 2 or 3 factors at once. But it’s going to be faster to know any possible positive outcome when you try all 6 ways to lower cholesterol in 1 food supplement than to try 6 different supplements, one at a time between 2 blood tests.

If really "nothing" works and I tried "all", only then will I opt for what the doctor prescribed: statins.

Why is it not wise to simply start taking the statins and forget about lifestyle changes? It would be as unwise as driving a tank in stead of driving a car in order to reduce one’s risk of mortality in a road accident… At the end of the day: the function of a disease is telling you that your body isn’t in an optimal state. Hence you should strive to discover the optimal state in stead of simply covering up the symptoms without tackling the underlying cause(s). When it comes to diets and food supplements: add healthy stuff in your body, so your body keeps healthy. Pharmaceutical drugs all come with possible side effects and doctors will look at the health of your liver before subscribing statins.

Are food supplements better than real food? In the case of plant sterols, you can only reach the recommended 2 grams a day by taking supplements or fortified foods. However, the complexity of all the known and unknown components and the synergy between them in whole foods, is not present in food supplements nor in fortified foods.

LDL conclusion

Lipoproteins are needed to carry the essential cholesterol around in your body. According to their density, they are classified from low to high as Chylomicrons, VLDL, LDL, HDL and VHDL.

Cholesterol in itself isn’t bad. The term "bad cholesterol" is given to the amount of LDL cholesterol found in your blood, and gives an estimation of the amount of LDL in your blood. High LDL levels are connected to cardio vascular disease.

In a lipid profile bloodtest, elevated levels of Low Density Lipoprotein Cholesterol attribute to one of the 10 risk factors for cardio vascular disease. The 9 other risk factors are:

1. smoking,
2. high blood pressure,
3. low HLD levels,
4. older age,
5. family history,
6. being overweight and
7. lack of physical activity
8. diabetes
9. elevated lipoprotein (a)

If your LDL cholesterol is high and you have 2 or more other risk factors, you are recommended to lower your LDL by changing your lifestyle: following a reduced yet "quality fat" diet and exercising more. If lifestyle changes don’t lower your cholesterol in a next bloodtest, doctors will prescribe cholesterol lowering drugs like statins sold as Lipitor.