Our class meets on Zoom Tuesday Sept 21st at 6:30 PM Est
HEAL Members are welcome to join us, if you would like a link for the class email or text Dara before 4pm Tuesday afternoon.
Cholesterol is usually seen as the enemy; a harmful substance we must try hard to lower in order to prevent heart attacks and strokes. The truth is, Cholesterol performs many vital functions in our body; the truth is we could not live with it. There are also very real negative health consequences associated with lowering our cholesterol too far, we will take a look at these.
Recent discoveries of a host of measurable substances in our blood that are proving to be much stronger predictors of our risk of heart disease than cholesterol. Substances such as Homocysteine, C-reactive protein, lipoprotein(a) and insulin all seem to be involved in the initiation and progression of heart disease, irrespective of our cholesterol level. Inflammation seems to be the major trigger for the development of atherosclerosis (fatty plaques in the arteries). Learning what causes inflammation and how we can reduce it in the body are key to better heart health.
Functions of Cholesterol
Membrane Function: Cholesterol forms part of the cell membrane of each cell in our body. Due to its being a hard fat, it gives the membranes rigidity and stability.
Synthesis of steroid hormones. The sex hormones estrogen, progesterone, DHEA and testosterone are made out of cholesterol.
Synthesis of adrenal hormones. The hormone aldosterone regulates water and sodium balance in the body and is made out of cholesterol. Cortisol is a hormone that regulates metabolism suppresses inflammation and is produces as a response to stress. When we are under chronic stress our bodies manufacture a great deal more cholesterol.
Bile production. 80% of the cholesterol in our body is used by the liver to produce bile salts. Bile is stored in the gallbladder and used to help in the digestion and absorption of dietary fats and fat soluble vitamins. This is the major route of exit of cholesterol from the body. Bile is secreted into our intestines and leaves the body in the bowel movements.
Vitamin D synthesis. Sunlight hitting our skin converts cholesterol into vitamin D, which is needed to keep our bones strong. Vitamin D has other important functions in our body; it boosts the immune system and helps to keep the blood pressure normal. Getting a bit of sunlight on our skin most days of the week can help to lower your cholesterol level by facilitating it conversion to vitamin D.
Skin Protection. Cholesterol is secreted into our skin, where it covers and protects us from dehydration, cracking and the drying effects of the elements. It helps to keep your skin looking plump and wrinkle free. Cholesterol has a role in healing, we know this because there are high amounts of it found in scar tissue.
Serotonin Function. Cholesterol is necessary for the function of serotonin receptors in the brain. Serotonin is a feel-good chemical that helps to protect us from depression. Several studies have shown that low cholesterol levels are associated with depression and violent behavior.
Myelin Sheath formation. Cholesterol is the main fat present in the myelin sheath, which coats our nerve cells and enables electrical impulses to occur in our brain and spinal cord. A healthy myelin sheath is needed for good concentration and memory
Antioxidant function. Cholesterol helps to transport fat soluble antioxidants around our body, such as vitamins E and A and several antioxidant enzymes.
Cholesterol and other fats in the bloodstream
Cholesterol is not very soluble in water; therefore it must be carried around the bloodstream in various transport molecules. Certain proteins called apolipoproteins can wrap around cholesterol and other blood fats (lipids) to form what is called lipoproteins; these are essentially a combination of protein and fat.
Class Handouts:
The Major fats in the bloodstream are:
Chylomicrons
These are the largest lipoproteins, and mainly transport fat from the intestines to the liver. They mainly carry triglyceride fats and cholesterol which come from the diet, and those manufactured by the liver.
Very Low Density Lipoprotein (VLDL)
These are the lowest density lipoproteins because they are highest in fat; (the denser the lipoprotein, the more protein it contains). VLDLs are made in the liver and deliver triglycerides to various tissues, especially muscle (for energy production), and body fat (for storage).
Low Density Lipoprotein (LDL)
This is the so called “bad cholesterol”. It is the major transporter of cholesterol and triglycerides, taking them from the liver to other parts of the body, where they can be used for various functions. You need your levels of LDL to be as low as possible.
There are other types of LDL:
Small dense LDL
This form of LDL is more likely to be taken up into the inner linings of arteries and promote atherosclerosis.
Oxidized LDL
This is what happens when free radicals cause damage to LDL molecules. This makes them more likely to promote damage to the inner lining of arteries, and for atherosclerosis to develop.
High Density Lipoprotein (HDL)
This is the so called “good Cholesterol”. It is high in protein which makes it denser and lower in cholesterol. This lipoprotein takes cholesterol from various parts of the body to the liver, where it can be excreted in bile. HDL carries antioxidant enzymes and vitamins to prevent the oxidation of LDL cholesterol You want your HDL to be as high as possible.
Triglycerides
These are a storage form of fat, made up of three fatty acids attached to a glycerol molecule. High triglyceride levels in the blood make it thick and sticky; they are a major risk factor for heart disease. Both excess carbohydrate and fat in our diet are converted into triglycerides in the liver.
Lipoprotein (a)
This particle is similar to LDL, but carries a sticky repair protein called apolipoprotein (a) which is used for tissue repair. It is a major risk factor for heart disease because it thickens the walls of the arteries.
Reasons for High Cholesterol
- 1) Poor Diet
- 2) Genetic factors
- 3) Hypothyroidism
- 4) Stress
- 5) Lack of Exercise
- 6) Smoking
Hazards of Low Cholesterol
- Aggressive behavior, Depression and Suicide
- Slower Brain Function
- Weak Immune System
- Hormone Deficiencies
- Shorter Life Span
- Greater risk of Cancer
How Low Should You Go
You should aim for a cholesterol Level of 183mg/dL to 214mg/dL.
Levels below 179mg/dl can be unhealthy. The all-cause death rate is higher in individuals with cholesterol levels lower than 178mg/dL
