http://heartdisease.about.com/cs/cholesterol/a/choltri.htm
Why they're important, who needs to be treated, how to treat
What is Cholesterol? What are triglycerides?
Cholesterol and triglycerides are two forms of lipid, or fat. Both cholesterol and triglycerides are necessary for life itself. Cholesterol is necessary, among other things, for building cell membranes and for making several essential hormones. Triglycerides, which are chains of high-energy fatty acids, provide much of the energy needed for cells to function.
Where do cholesterol and triglycerides come from?
There are two sources for these lipids: dietary sources, and endogenous sources (i.e., manufactured within the body).
Dietary cholesterol and triglycerides mainly come from eating animal products and saturated fat. These dietary lipids are absorbed through the gut,and then are delivered through the bloodstream to the liver, where they are processed.
One of the main jobs of the liver is to make sure all the tissues of the body receive the cholesterol and triglycerides they need to function.
Sponsored Links
What's Your RealAge?
Is your high cholesterol aging you? Take the free RealAge test.
www.realage.com
Endur-acin®
SR Niacin (Nicotinic Acid) Research demonstrates good efficacy
http://www.endur.com
Lower Your Cholesterol
by up to 41% in 60 days or less. Proven safe. Guaranteed results!
www.menshealthtech.com
Whenever possible (i.e., for about 8 hours after a meal), the liver takes up dietary cholesterol and triglycerides from bloodstream. During times when dietary lipids are not available, the liver produces cholesterol and triglycerides itself.
The liver then packages the cholesterol and triglycerides, along with special proteins, into tiny spheres called lipoproteins. The lipoproteins are released into the circulation, and are delivered to the cells of the body. The cells remove the needed cholesterol and triglycerides from the lipoproteins, as they are needed.
What are LDL and HDL?
LDL stands for ???low density lipoprotein,??? and HDL for ???high density lipoprotein.??? In the bloodstream, ???bad??? cholesterol is carried in LDL, and ???good??? cholesterol is carried in HDL. Most cholesterol in the blood comes from LDL. Only a small proportion is from HDL cholesterol. Thus, the total cholesterol level in the blood is usually a reflection of the amount of LDL cholesterol.
Why are high cholesterol levels bad?
When LDL cholesterol levels (i.e., the ???bad??? cholesterol) are too high, the LDL tends to stick the lining of the blood vessels, leading to the stimulation of ???atherosclerosis,??? or hardening of the arteries. Atherosclerotic ???plaques??? cause narrowing of the arteries, and lead to heart attacks and strokes. Therefore, an elevated LDL cholesterol levels is a major risk factor for heart disease and stroke.
Why is some cholesterol called ???good cholesterol????
Much evidence has now accumulated that increased HDL cholesterol levels are associated with a lower risk of heart disease, and that low HDL cholesterol levels are associated with an increased risk of heart disease. Thus, HDL cholesterol appears to be ???good.???
Why is HDL cholesterol protective? Nobody knows for sure, but it appears that it???s not the cholesterol itself that is good, it???s the "vehicle." There is some evidence that the HDL molecule ???scours??? the walls of blood vessels, and cleans out excess cholesterol. If this is the case, the cholesterol being carried by HDL (that is, the ???good??? HDL cholesterol) is actually ???bad??? cholesterol that has just been removed from blood vessels, and is being transported back to the liver for further processing. Apparently, unlike some bad humans, bad cholesterol can be rehabilitated.
Why are triglycerides the Rodney Dangerfield of lipids?
Triglycerides get little respect. Their measurement is part of a standard blood lipid profile, but for the most part doctors don???t know what to do when triglyceride levels are modestly elevated. Why is that? While high triglyceride levels have been associated with heart disease, no study has yet proven that high triglyceride levels are an independent risk factor for heart disease. So doctors don???t have the evidence they need to recommend aggressive triglyceride-lowering therapy.
The problem is, patients with elevated triglyceride levels almost invariably have other major risk factors for heart disease (mainly obesity, diabetes, and/or high blood pressure), and so far it has not been possible to sort out whether the triglycerides themselves pose an independent risk.
The most difficult-to-sort-out association is that between triglycerides and HDL cholesterol. It turns out that whenever triglycerides are increased, HDL cholesterol decreases. So is the increased risk seen with high triglycerides due to the triglycerides themselves, or to the associated reduction in ???good??? cholesterol? So far, nobody can say for sure.
However, recent evidence strongly suggests that an elevated triglyceride level is a significant risk factor for cardiac disease - especially when it is elevated as part of the "metabolic syndrome X." Click here for a brief review of metabolic syndrome X.
Why they're important, who needs to be treated, how to treat
What is Cholesterol? What are triglycerides?
Cholesterol and triglycerides are two forms of lipid, or fat. Both cholesterol and triglycerides are necessary for life itself. Cholesterol is necessary, among other things, for building cell membranes and for making several essential hormones. Triglycerides, which are chains of high-energy fatty acids, provide much of the energy needed for cells to function.
Where do cholesterol and triglycerides come from?
There are two sources for these lipids: dietary sources, and endogenous sources (i.e., manufactured within the body).
Dietary cholesterol and triglycerides mainly come from eating animal products and saturated fat. These dietary lipids are absorbed through the gut,and then are delivered through the bloodstream to the liver, where they are processed.
One of the main jobs of the liver is to make sure all the tissues of the body receive the cholesterol and triglycerides they need to function.
Sponsored Links
What's Your RealAge?
Is your high cholesterol aging you? Take the free RealAge test.
www.realage.com
Endur-acin®
SR Niacin (Nicotinic Acid) Research demonstrates good efficacy
http://www.endur.com
Lower Your Cholesterol
by up to 41% in 60 days or less. Proven safe. Guaranteed results!
www.menshealthtech.com
Whenever possible (i.e., for about 8 hours after a meal), the liver takes up dietary cholesterol and triglycerides from bloodstream. During times when dietary lipids are not available, the liver produces cholesterol and triglycerides itself.
The liver then packages the cholesterol and triglycerides, along with special proteins, into tiny spheres called lipoproteins. The lipoproteins are released into the circulation, and are delivered to the cells of the body. The cells remove the needed cholesterol and triglycerides from the lipoproteins, as they are needed.
What are LDL and HDL?
LDL stands for ???low density lipoprotein,??? and HDL for ???high density lipoprotein.??? In the bloodstream, ???bad??? cholesterol is carried in LDL, and ???good??? cholesterol is carried in HDL. Most cholesterol in the blood comes from LDL. Only a small proportion is from HDL cholesterol. Thus, the total cholesterol level in the blood is usually a reflection of the amount of LDL cholesterol.
Why are high cholesterol levels bad?
When LDL cholesterol levels (i.e., the ???bad??? cholesterol) are too high, the LDL tends to stick the lining of the blood vessels, leading to the stimulation of ???atherosclerosis,??? or hardening of the arteries. Atherosclerotic ???plaques??? cause narrowing of the arteries, and lead to heart attacks and strokes. Therefore, an elevated LDL cholesterol levels is a major risk factor for heart disease and stroke.
Why is some cholesterol called ???good cholesterol????
Much evidence has now accumulated that increased HDL cholesterol levels are associated with a lower risk of heart disease, and that low HDL cholesterol levels are associated with an increased risk of heart disease. Thus, HDL cholesterol appears to be ???good.???
Why is HDL cholesterol protective? Nobody knows for sure, but it appears that it???s not the cholesterol itself that is good, it???s the "vehicle." There is some evidence that the HDL molecule ???scours??? the walls of blood vessels, and cleans out excess cholesterol. If this is the case, the cholesterol being carried by HDL (that is, the ???good??? HDL cholesterol) is actually ???bad??? cholesterol that has just been removed from blood vessels, and is being transported back to the liver for further processing. Apparently, unlike some bad humans, bad cholesterol can be rehabilitated.
Why are triglycerides the Rodney Dangerfield of lipids?
Triglycerides get little respect. Their measurement is part of a standard blood lipid profile, but for the most part doctors don???t know what to do when triglyceride levels are modestly elevated. Why is that? While high triglyceride levels have been associated with heart disease, no study has yet proven that high triglyceride levels are an independent risk factor for heart disease. So doctors don???t have the evidence they need to recommend aggressive triglyceride-lowering therapy.
The problem is, patients with elevated triglyceride levels almost invariably have other major risk factors for heart disease (mainly obesity, diabetes, and/or high blood pressure), and so far it has not been possible to sort out whether the triglycerides themselves pose an independent risk.
The most difficult-to-sort-out association is that between triglycerides and HDL cholesterol. It turns out that whenever triglycerides are increased, HDL cholesterol decreases. So is the increased risk seen with high triglycerides due to the triglycerides themselves, or to the associated reduction in ???good??? cholesterol? So far, nobody can say for sure.
However, recent evidence strongly suggests that an elevated triglyceride level is a significant risk factor for cardiac disease - especially when it is elevated as part of the "metabolic syndrome X." Click here for a brief review of metabolic syndrome X.
