What are cholesterol and Triglycerides?
Cholesterol is a fat like substance essential for life. Only 20% of cholesterol in your blood comes from food like meat, fish, poultry, eggs,whole milk and dairy products. 80% of the cholesterol is manufactured in your body, mainly in the liver. Since they are fatty and cannot dissolve in the watery fluid of the blood, they are carried by special protein called lipoproteins.
The names of these lipoproteins may be familiarto many
- Low Density Lipoproteins (LDL) and Very Low Density Lipoproteins (VLDL) LDLs have high level of cholesterol and hence called ‘bad’ cholesterol. LDLs are associated with high risk for heart attack. VLDLs are high in triglycerides
- High Density Lipoproteins (HDL)have low levels of cholesterol and called ‘good cholesterol. Higher the HDL the better for your heart.
- Triglycerides are a type of fat, responsible for providing energy to the cells of the body. All dietary fat and oils contain triglycerides. They contain mixtures of Saturated Fatty Acids (SFA), Mono Unsaturated Fatty Acid (MUFA) and Poly Unsaturated Fatty Acid (PUPA)
How is cholesterol measured?
It is measured using a test called Lipid Profile. It is actually a group of tests that are often collectively ordered to determine whether a person is at risk for developing Coronary Artery Disease.This includes total cholesterol, HDL cholesterol, LDL cholesterol, VLDL Cholesterol, triglycerides and certain ratios
What are the targets for cholesterol?
Targets for cholesterol are
- Total cholesterol levels: 200 mg/dl or below.
- LDL cholesterol levels: 100 mg/dl or below. (The lower the better)
- HDL cholesterol levels: more than 45 mg/dL for men and more than 50 mg/dL for women, with everyone aiming for about 60. (The higher the better)
- Triglyceride levels: 150 mg/dL or lower.
Elevated levels of other lipids, including lipoprotein (a) and apolipoprotcin A-l and B are also now thought to be important indicators of heart risk.
What are the factors presently known to increase HDL levels and decrease LDL levels?
Physical activity, use of vegetable fat and oil instead of animal fat, no smoking, normal weight, normal total cholesterol, normal triglycerides, normal sugar and low-moderate alcohol intake are some of the favorable factors known to increase HDL levels and decrease LDL levels.Almost all the factors listed above are modifiable and depend largely on the choice we make. Since heart disease appears to be caused by multiple factors, reducing only one factor may not have the desired impact.
Recent studies have shown that quitting smoking, taking up regular exercise, consuming vegetarian diet, fish and skimmed milk products can definitely lower the LDL levels.
How is the Lipid Profile test done?
Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and an elastic band or blood pressure cuff is placed around the upper arm to apply pressure and restrict blood flow through the vein. This causes veins to fill with blood. A needle is inserted into the vein and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation and prevent bruising. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
How to prepare for the test?
To get accurate results, you should fast for 9 to 12 hours before the test. The doctor may advise you to stop taking drugs that can affect the test. You may drink water during the fast, but other beverages such as coffee, tea, or soda may affect results.
Who should take drugs to lower cholesterol levels?
Statins are drugs used by doctors to lower bad cholesterol. They also reduce risk of heart attacks and stroke in those who have other risks for heart disease.
Currently we use the guidelines issued by the American College of Cardiology in November2013
- People with a history of heart attack or heart disease
- People with Type -1 or Type -2 Diabetes who are between 40- 75 years
- People who are 21 years or older with a high level of LDL cholesterol ( more than 190mg/dL)
- People without cardiovascular disease who are between 40-75 years and have a 7.5 % risk for having a heart attack or stroke within 10 years.
Doctors have to make a judgement whether you need to be in statins even if you have absolutely normal cholesterol levels. Since there is strong evidence that statins are heart protective the current thinking is to address the risk and not just the cholesterol levels.