Cholesterol

Smětalová Dagmar

Franková Tamara

Structure

Cholesterol has a molecular formula C27H45OH. This molecule is composed of three regions (shown in the picture): – a hydrocarbon tail (shown in blue)– a ring structure region with 4

hydrocarbon rings (shown in green)– a hydroxyl group (shown in red)

Cholesterol is a sterol (a combination of steroid and alcohol) and a lipid found in the cell membranes of all body tissues, and transported in the blood plasma of all animals.

Function of cholesterol

• is the major precursor for the synthesis of vitamin D and of the various steroid hormones (cortisol and aldosterone in the adrenal glands, sex hormones progesterone, estrogen, and testosterone)

• further recent research shows that cholesterol has an important role for the brain synapses as well as in the immune system, including protecting against cancer

digest – trávitadrenal glands - nadledvinky

required – nutnýmaintain – udržovatbile - žluč

• is required to build and maintain cell membranes • aids in the manufacture of bile (which helps digest fats)• is important for the metabolism of fat soluble vitamins (vitamins A, D, E and K)

Cholesterol is made of two kinds of cholesterol: LDL – low-density lipoprotein is the „bad“

cholesterol HDL – high-density lipoprotein is the

„good“ cholesterol

HDLs differ from LDLs both in composition and function. HDLs consist of 40-55% protein and LDLs consist of 20-25% protein. The rest of the lipoproteins are lipids, so LDLs are much richer in lipids than HDLs.

Why is LDL cholesterol considered "bad"?

When too much LDL cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances it can form plaque, a thick, hard deposit that can clog those arteries. This condition is known as atherosclerosis. If a clot forms and blocks a narrowed artery, it can cause a heart attack or stroke.

considered – považovanýbuild up – usazovat sedeposit – usazeninaclog – ucpatclot - sraženinaheart attack – infarktstroke - mrtvice

Why is HDL cholesterol considered "good"?

About one-third to one-fourth of blood cholesterol is carried by high-density lipoprotein (HDL). HDL cholesterol is known as the "good" cholesterol because a high level of it seems to protect against heart attack. Medical experts think that HDL tends to carry cholesterol away from the arteries and back to the liver, where it's passed from the body. Some experts believe that HDL removes excess cholesterol from plaque in arteries, thus slowing the buildup.

excess – nadbytek

buildup - nahromadění

Top Twenty Foods High in Cholesterol

Test your Cholesterol IQ

Take this simple quiz...

1. Most of your blood cholesterol is produced by:

a.) Your liver

b.) Your pancreas

c.) Food consumption

d.) Your kidneys

a.) Your liver. Your liver produces about 1,000 mg of cholesterol a day - all the cholesterol your body needs. Another 200 to 500 mg can come from the food you eat.

2. Only adults need to have their cholesterol checked. Children can't have high cholesterol.

a.) True b.) False

b.) False. Compelling evidence shows that the atherosclerotic process starts in childhood and progresses slowly into adulthood. Children from high-risk families (parents with high cholesterol, or parents or grandparents with heart disease at 55 years or younger) should have their cholesterol levels tested.

3. All I really need to know is my total blood cholesterol number.

a.) True b.) False

b.) False. Your blood cholesterol is made up LDL “bad” cholesterol and HDL “good” cholesterol. You need to know triglyceride level, too. Triglyceride is a form of fat. It is made in your body and also comes from food. People with high triglycerides often have high total cholesterol, high LDL cholesterol and a low HDL cholesterol level.

4. You know you have high cholesterol when

a.) You have a lot of headaches

b.) You start to gain weight.

c.) Your blood pressure is high

d.) You have it checked by a doctor

d.) You have it checked by a doctor. High cholesterol has no symptoms, so the only way to know your cholesterol levels is by having them checked

5. If I have high cholesterol, the only thing I can do about it is take medication.

a.) True b.) False

b.) False. First and foremost you should check your lifestyle habits. Are you a smoker? Do you eat too much saturated fat or cholesterol? Are you physically inactive? All of these factors can affect your cholesterol levels.

More question at www.americanheart.org

Sources

• http://en.wikipedia.org• http://www.cholesterol-and-health.com• http://www.americanheart.org• http://www.shodor.org

Thank you for your attention!