The first and most important point is that CHOLESTEROL IS ESSENTIAL TO LIFE! Its major biological value can be gauged by the following facts:
- All of the cell membranes in our body require cholesterol in their structure, this is where 90% of the body’s cholesterol is found.
- Our brains and nerve tissue contain 25% of the body’s cholesterol and the brain by weight is ⅕
- The brain and nerves require cholesterol for a host of normal functions.
- Cholesterol is required in all cellular repair.
- All our steroid hormones including our sex hormones like testosterone and oestrogen are made from cholesterol.
- Vitamin D which is essential for bone health, weight management, mental & immune function is made from cholesterol.
- Bile which we release from our gallbladder to digest & absorb essential fats and vitamins (Vits A,D,E,K) is made from cholesterol.
- Cholesterol is a vital cog in the normal function of our immune system.
So bottom line ……no cholesterol……no sex! No cholesterol ……..no life!
If you thought that we get cholesterol from our food, you are wrong! The chief source of cholesterol in the body is from internal liver and cell production which accounts for more than 85% of the body’s cholesterol. The cholesterol in our diet from foods like eggs and meat makes little or no contribution to measured (blood) cholesterol levels.
The next interesting bit of information relates to the relationship between cholesterol and dietary saturated fat:
- Cholesterol is biochemically a sterol which is not the same as a fat.
- Cholesterol and fat share common dietary sources like eggs, meat, liver and dairy.
- Cholesterol is secreted in bile so that fat digestion can take place in the intestine.
- Both cholesterol and fats are ‘lipids’ which means a substance that does not dissolve in water (or blood); they therefore require a special transport system in the body.
- Cholesterol and fat share the (lipoprotein) body transport system in the bloodstream which means they are both transported through the blood in the same “Taxis” known as very low density lipoprotein VLDL, low density lipoprotein LDL and high density lipoprotein HDL.
- When the liver manufactures a lot of fats (triglycerides) from sugar and refined carbs then it secretes these fats inside VLDL.
- LDL is not cholesterol but is formed from VLDL and transports cholesterol along with fats (triglycerides) from the liver to the body’s cells including the brain.
- 70% of the body’s circulating cholesterol is carried in LDL.
- LDL levels are regulated by cell receptors especially in the liver which can take up more or less LDL as and when required in order to maintain LDL levels (people with Familial Hypercholesterolaemia (FH) have a deficiency of these LDL receptors resulting in very elevated LDL cholesterol levels up to 5x normal).
- HDL transports cholesterol from the body tissues back to the liver and is also an antioxidant.
The modern understanding of cholesterol and heart disease risk:
- There is no such thing as ‘good’ or ‘bad’ cholesterol, cholesterol is cholesterol!
- Total cholesterol as a blood test is a weak predictor of future heart disease.
- More than half of all heart attacks occur in people with ‘normal’ cholesterol levels.
- Increased heart attack risk is associated with:
- An increase in the number of small dense LDL particles
- Low levels of HDL
- Elevated levels of blood triglycerides (fats)
- Elevated levels of oxidised (“damaged”) LDL particles