What is Cholesterol
Cholesterol is a waxy, fat-like substance that is made in the body and also is found in animal sources including milk, cheese, eggs & meat. A certain amount of cholesterol is an essential part of a healthy diet, but when it is taken in excess, health complications can arise, such as arterial blockages.
Where does Cholesterol come from?
About 80% of the cholesterol in our bodies is made in the liver and the remaining 20% is taken in from our diets. A small amount of cholesterol is also made by the lining of the small intestine and the individual cells of the body.
If we eat a diet that is high in cholesterol-rich foods, then the levels of cholesterol in our bodies can increase more than we need and can start to cause health problems and complications in the circulation and heart.
The Functions of Cholesterol
Cholesterol has many vital functions in the body including:
- Helping to maintain healthy cell membranes
- Assisting in the production of hormones - Chemical substances formed in one part of the body that are carried in the blood to another part of the body before they act.
- Cholesterol is used by the body to produce bile salts that are used in the digestive process to break down food.
When the skin is exposed to direct sunlight, Cholesterol helps to convert the sunlight into Vitamin D in the fat cells in under the skin.
How Cholesterol Travels Around the Body
Cholesterol is not very soluble in water. In order to move around our bloodstream it must be carried in some form of transport molecules. Cholesterol is carried around the blood stream in molecules made of proteins and fat. These are called Lipoproteins.
Good Cholesterol versus Bad Cholesterol
For the sake of simplicity, there are two sorts of cholesterol: a 'good' sort called high-density lipoprotein (HDL) and a 'bad' sort called low-density lipoprotein (LDL).
High Density Lipoprotein helps to reduce the levels of cholesterol in the blood and transports it back to the liver. It is thought that this HDL actually protects against atherosclerosis.
Low Density Cholesterol can contribute to heart and circulation problems, especially when there is more L.D.L. than H.D.L.
Possible Health Risks from Too Much Cholesterol
Large deposits of cholesterol can block an artery. Having too much cholesterol in the arteries can literally cause them to harden and bring about a condition known as atherosclerosis. This is when there is a build up of cholesterol plaque on the inside of blood vessels. Atherosclerosis refers to the build up of fatty deposits called plaques in the walls of the arteries.
Atherosclerosis is often called arteriosclerosis, which literally comes from the Greek arteria, meaning artery and is a general term for hardening of the arteries.
Fatty deposits - or Cholesterol plaques - can also lead to the formation of a blood clot that blocks the flow of blood. If an artery that supplies blood to the muscles in your heart becomes blocked, a heart attack can occur. If an artery that supplies blood to your brain becomes blocked, a stroke can occur. It is wise therefore to regulate the amount of cholesterol that one eats.
Food Sources that help to raise Good Cholesterol or H.D.L. Levels
By eating foods that are high in the good cholesterol or High Density Lipoproteins, it is possible to maintain healthy levels of cholesterol in the blood. Here are some food sources of good cholesterol in the body:
- Omega-3 acids
- Soluble fibres – such as whole grains, oats and oat bran, brown rice.
- These help to lower total cholesterol levels and raise the levels of High Density Lipoproteins.
- Fruits such as oranges, lemons, apples, grapes
- Legumes & lentils.
- Cooking oils such as canola or olive oil. Oils that are high in monounsaturated fats raise the levels of good Cholesterol.
- Fish, cold-pressed flaxseed oil, safflower oil, sunflower oil, dark green vegetables contain Omega 3 oils.
- Soy products such as tofu, tempeh may also help.
- Regular, gentle exercise in fresh air helps to maintain health.
Foods Sources of Bad Cholesterol or Low Density Lipoproteins
Trans Fats including hydrogenated oil or vegetable shortening are sources of bad cholesterol or Low Density Lipoproteins.
Trans fatty acids are found in and many fast foods and French fries, baked goods such as cookies, crackers and cakes. Remember, the softer the spread, the less Trans fat it contains. Refined carbohydrates like sugar and refined flour.
Foods that are themselves high in cholesterol include:
- Egg yolk
- Regular Milk
- Hard cheeses
- Refined carbohydrates like sugar and refined flour.
More on Cholesterol
The extra cholesterol in your blood may be stored in your arteries as plaque. This causes the arteries to narrow and harden and eventually creates a condition called arteriosclerosis.
Possible Health Risks from Too Much Cholesterol
Large deposits of cholesterol can block an artery. Having too much cholesterol in the arteries can literally cause them to harden and bring about a condition known as atherosclerosis. This is when there is a build up of cholesterol plaque on the inside of blood vessels.
Atherosclerosis is often called arteriosclerosis which literally comes from the Greek arteria, meaning artery and is a general term for hardening of the arteries.
Cholesterol plaques can also lead to the formation of a blood clot that blocks the flow of blood. If an artery that supplies blood to the muscles in your heart becomes blocked, a heart attack can occur. If an artery that supplies blood to your brain becomes blocked, a stroke can occur. It is wise therefore to regulate the amount of cholesterol that one eats.
Good Fats destroyed by Hydrogenation
Hydrogenation increases the shelf life and flavour stability of foods containing these fats but on the other hand it raises the levels of what is called ‘Bad Cholesterol’. As Trans Fats raise the levels of ‘Bad Cholesterol’ in the blood, it is wise to look out for them on the ingredient labels on foods, pies and pastries.
Hydrogenation helps to make shortening. Shortening is a solid, flavourless fat product that will keep its form regardless of room temperature, and not puddle or pool like butter or other animal fats do on hot days or in warm rooms. The disadvantage is a health one: the process creates Trans-fatty acids and saturated fat which is bad, and destroys the normal polyunsaturated benefits of the vegetable oil that it started from.
If a liquid fat such as sunflower oil is solidified by a chemical process known as hydrogenation, it is becomes a Trans fat, a chemical process that solidifies the oil. Trans in this sense comes from the Latin word meaning ‘across’ and is to do with the chemical process of solidifying the oil.
Hydrogenation of fats increases their shelf-life so it is widely used in the food industry to create longer-lasting margarine and fats that in turn create longer lasting cakes, biscuits and pie pastries.
The trouble with Trans fats is that they interfere with the body's ability to regulate cholesterol.
In many countries it is now part of food law that Food Manufacturing companies have to label the Trans fat content of food. Trans fat raises the level of bad cholesterol or Low Density Lipoproteins in the body.
Another name for Trans-fats is “partially hydrogenated oils."
Potential food sources of Trans fats: Always check the label:
- Fried foods in some food chains
- Vegetable shortening – used in cooking
- Microwave popcorn
Shortening is a white semisolid fat used in food preparation, especially baked goods, and is so called because it promotes a "short" or crumbly texture (as in shortbread). Shortening is fat or lard from an animal or vegetable. Shortening is made from vegetable oils, using the technique known as hydrogenation discovered at the beginning of the 1900s.
In the UK, shortening is available under brand names such as Coquina, Trex, White Flora, etc. Shortening has 100% fat content, compared to about 80% for butter and margarine.