Saturday, July 9, 2016
Cholesterol is a fatty substance carried around the body by proteins. When cholesterol and proteins are combined, they are called lipoproteins. There are two
main types of lipoproteins:
Low-density lipoproteins (LDL) is known as the bad type of cholesterol. LDL carry cholesterol from your liver to the cells that need it.
High-density lipoprotein (HDL) is known as the good type of cholesterol. HDL carry cholesterol away from the cells and back to the liver to be broken down.
Too much bad cholesterol (LDL) in your blood can cause fatty material to build up in your artery walls. The risk is particularly high if you have a high level of bad cholesterol and a low level of good cholesterol.
If you need to have your cholesterol measured, it will be in units called millimols per litre of blood (mmol/l). You should aim to have a total cholesterol level under 4mmol/l especially if you are at risk of, or already have, heart and circulatory disease. You should also aim to have your LDL under 2 mmol/l and your HDL above 1 mmol/l.
- High cholesterol can create a bile imbalance, leading to gallstones. According to the National Digestive Disease Information Clearinghouse, more than 80 percent of gallstones are cholesterol stones.
A buildup of plaque in your arteries can also block blood flow to your kidneys and stomach. Intestinal ischemic syndrome is when there’s a blockage in arteries leading to the intestines or bowel. Symptoms include abdominal pain, nausea, vomiting, and bloody stools.
- causes high cholesterol
There is no one single cause for high cholesterol. Many different factors can contribute to high cholesterol such as:
eating a diet that is high in saturated fat
smoking
lack of physical activity
high alcohol intake, or
kidney or liver disease.
Having an inherited condition known as familial hypercholesterolaemia (FH) can also cause exceptionally high cholesterol even if you have a healthy lifestyle.
"If you want to see what it looks like in a solidified form, go get yourself a can of Crisco at the grocery store," says Gregory Dehmer, MD, director of the division of cardiology at the Texas A&M College of Medicine. "If you open up a can of Crisco, its this white, lard-like substance."
main types of lipoproteins:
Low-density lipoproteins (LDL) is known as the bad type of cholesterol. LDL carry cholesterol from your liver to the cells that need it.
High-density lipoprotein (HDL) is known as the good type of cholesterol. HDL carry cholesterol away from the cells and back to the liver to be broken down.
Too much bad cholesterol (LDL) in your blood can cause fatty material to build up in your artery walls. The risk is particularly high if you have a high level of bad cholesterol and a low level of good cholesterol.
If you need to have your cholesterol measured, it will be in units called millimols per litre of blood (mmol/l). You should aim to have a total cholesterol level under 4mmol/l especially if you are at risk of, or already have, heart and circulatory disease. You should also aim to have your LDL under 2 mmol/l and your HDL above 1 mmol/l.
- High cholesterol can create a bile imbalance, leading to gallstones. According to the National Digestive Disease Information Clearinghouse, more than 80 percent of gallstones are cholesterol stones.
A buildup of plaque in your arteries can also block blood flow to your kidneys and stomach. Intestinal ischemic syndrome is when there’s a blockage in arteries leading to the intestines or bowel. Symptoms include abdominal pain, nausea, vomiting, and bloody stools.
- causes high cholesterol
There is no one single cause for high cholesterol. Many different factors can contribute to high cholesterol such as:
eating a diet that is high in saturated fat
smoking
lack of physical activity
high alcohol intake, or
kidney or liver disease.
Having an inherited condition known as familial hypercholesterolaemia (FH) can also cause exceptionally high cholesterol even if you have a healthy lifestyle.
"If you want to see what it looks like in a solidified form, go get yourself a can of Crisco at the grocery store," says Gregory Dehmer, MD, director of the division of cardiology at the Texas A&M College of Medicine. "If you open up a can of Crisco, its this white, lard-like substance."
His Heart Almost Stopped
How cholesterol can clog arteries
Not all cholesterol is created equal. It's a fatty substance, so cholesterol can't dissolve in the blood to be carried to where it's needed in the body. "Your body is mostly water, and fat and water don't mix," says Dr. Dehmer.
So cholesterol is packaged into proteins that can shuttle the fatty stuff around your body. One is high-density lipoprotein (HDL, or good cholesterol) and another is low-density lipoprotein (LDL, or bad cholesterol).
What's the difference? LDL can stick to the smooth lining of the blood vessels, where it is absorbed. HDL appears to do the opposite—it actually mops up excess cholesterol and removes it from the blood vessels.
The amount and type of cholesterol in your blood are determined by genetics, age, diet, and exercise. When you eat a diet that's rich in saturated and trans fats, or dietary cholesterol (which is found in animal products such as eggs, milk, and meat), LDL cholesterol levels go up.
"The problem is that many individuals—and probably including myself—eat a diet that is very excessive in all the wrong kind of fats, of which we are talking about animal fats and dairy fats, and therefore we get our cholesterol up too high," says Dr. Dehmer.
But when you exercise, HDL cholesterol goes up—and that's a good thing. "The bottom line is that there are some people out there who have fairly high levels of HDL cholesterol," says Stephen Nicholls, MBBS, PhD, a research cardiologist at the Cleveland Clinic. "That may drive their total cholesterol to look higher than it actually is in terms of how bad that level is."
How cholesterol affects the heart
If LDL cholesterol is too high, some is absorbed into the artery walls, where it acts like an irritant that triggers inflammation in the body. White blood cells crawl into the artery wall and start "gobbling up fatty particles" in a fruitless effort to heal the damage, says Dr. Dehmer.
The end result is big, fatty deposits in the blood vessels. This causes the vessels to become stiff, narrow, and less responsive to triggers to expand and constrict, a process that ensures a steady flow of life-giving oxygen to the body's tissues. (While you may think of blood vessels as akin to the plumbing in your house, they're more dynamic; they constantly adapt to meet the body's needs.)
open quoteIf you want to see what cholesterol looks like, go get yourself a can of Crisco at the grocery store.close quote
This process can happen all over your body. If the fatty buildup is in the blood vessels in the legs (a condition known as peripheral arterial disease), you may experience cramping and have difficulty walking; if it's in the penis, you can develop erectile dysfunction; and if it's in the neck arteries, it can cut off the blood supply to the brain and cause a stroke.
The biggest danger, however, is to the heart. The arteries that cover the surface of the heart are particularly prone to clogging. Once fatty plaques clog these blood vessels, blood flow to the heart tissue is reduced. This can cause chest pain, or angina.
If plaque ruptures, a clot can form and cause a heart attack—a dramatic decline in the blood supply that causes heart tissue to die. (To find out if youre at risk for having a heart attack, take this test.)
What you can do about bad cholesterol
The artery-clogging process can start early in life. A 2008 autopsy study of adults ages 16 to 64 who died of non-heart-disease-related causes found that 83% had signs of heart disease and 8% had advanced disease. "We're seeing evidence of abnormality of blood vessels and obvious plaque in teenagers," says Dr. Nicholls.
Luckily, there are many things you can do to help prevent this process. "We know that lowering LDL cholesterol, the bad form, is clearly a good thing," says Dr. Nicholls. "The other thing we would highlight is the emerging role of HDL, or good cholesterol, the other player here."
Diet and exercise are critical for lowering LDL and raising HDL, notes Dr. Nicholls. (Click here for specific lifestyle changes that can lower heart disease risk.)
Cholesterol-lowering medication can also help, but you still need to watch your diet and exercise. "You can't just say, 'I'm being treated, so I can therefore not exercise and eat whatever I want,'" says Dr. Nicholls. "It doesn't work that way."
How can I reduce my cholesterol level?
Eat a healthy balanced diet
Eating lots of fruit, vegetables, and wholegrain is better than eating foods high in saturated or trans fats. You can replace saturated fats with the healthy monounsaturated and polyunsaturated fats such as olive, rapeseed or sunflower oils and spreads.
Choose foods that are high in soluble fibre such as oats, beans, pulses, lentils, nuts, fruits and vegetables. Soluble fibre can help lower cholesterol.
Do regular exercise
Regular physical activity can help increase your HDL cholesterol (the good type of cholesterol). Staying active is great way to keep your heart healthy.
Quit smoking
Quitting smoking can help to lower your cholesterol and improve your heart health.
Will I need to take medication?
Whether or not you need to take cholesterol-lowering medicine depends on your overall risk of cardiovascular disease.
Cholesterol-lowering medicines such as statins are prescribed for people who are at greatest overall risk of cardiovascular disease. If you have questions about your medicines, speak with your doctor or call our Heart Helpline on 0300 330 3311. You can also look at our publications for more information.
Will eating sterol-enriched foods help reduce my cholesterol level?
Although the effect varies between individuals, there is evidence to show that plant sterols and stanols can help to reduce LDL cholesterol by levels up to 10-15% when 2g per day is regularly consumed as part of a healthy balanced diet.
But whilst there is an expectation that this would lead to fewer heart attacks, no clinical trials have been undertaken to show this. Sterols and stanols have been added to certain foods, including margarines, spreads, soft cheeses and yoghurts.
Will eating too many eggs raise my cholesterol?
For most people, the amount of saturated fat they eat has much more of an impact on their cholesterol than eating foods that contain cholesterol, like eggs, liver, kidneys and shellfish. Unless you have been told otherwise by your doctor or dietician, if you like eggs, they can be included as part of a balanced and varied diet
How cholesterol can clog arteries
Not all cholesterol is created equal. It's a fatty substance, so cholesterol can't dissolve in the blood to be carried to where it's needed in the body. "Your body is mostly water, and fat and water don't mix," says Dr. Dehmer.
So cholesterol is packaged into proteins that can shuttle the fatty stuff around your body. One is high-density lipoprotein (HDL, or good cholesterol) and another is low-density lipoprotein (LDL, or bad cholesterol).
What's the difference? LDL can stick to the smooth lining of the blood vessels, where it is absorbed. HDL appears to do the opposite—it actually mops up excess cholesterol and removes it from the blood vessels.
The amount and type of cholesterol in your blood are determined by genetics, age, diet, and exercise. When you eat a diet that's rich in saturated and trans fats, or dietary cholesterol (which is found in animal products such as eggs, milk, and meat), LDL cholesterol levels go up.
"The problem is that many individuals—and probably including myself—eat a diet that is very excessive in all the wrong kind of fats, of which we are talking about animal fats and dairy fats, and therefore we get our cholesterol up too high," says Dr. Dehmer.
But when you exercise, HDL cholesterol goes up—and that's a good thing. "The bottom line is that there are some people out there who have fairly high levels of HDL cholesterol," says Stephen Nicholls, MBBS, PhD, a research cardiologist at the Cleveland Clinic. "That may drive their total cholesterol to look higher than it actually is in terms of how bad that level is."
How cholesterol affects the heart
If LDL cholesterol is too high, some is absorbed into the artery walls, where it acts like an irritant that triggers inflammation in the body. White blood cells crawl into the artery wall and start "gobbling up fatty particles" in a fruitless effort to heal the damage, says Dr. Dehmer.
The end result is big, fatty deposits in the blood vessels. This causes the vessels to become stiff, narrow, and less responsive to triggers to expand and constrict, a process that ensures a steady flow of life-giving oxygen to the body's tissues. (While you may think of blood vessels as akin to the plumbing in your house, they're more dynamic; they constantly adapt to meet the body's needs.)
open quoteIf you want to see what cholesterol looks like, go get yourself a can of Crisco at the grocery store.close quote
This process can happen all over your body. If the fatty buildup is in the blood vessels in the legs (a condition known as peripheral arterial disease), you may experience cramping and have difficulty walking; if it's in the penis, you can develop erectile dysfunction; and if it's in the neck arteries, it can cut off the blood supply to the brain and cause a stroke.
The biggest danger, however, is to the heart. The arteries that cover the surface of the heart are particularly prone to clogging. Once fatty plaques clog these blood vessels, blood flow to the heart tissue is reduced. This can cause chest pain, or angina.
If plaque ruptures, a clot can form and cause a heart attack—a dramatic decline in the blood supply that causes heart tissue to die. (To find out if youre at risk for having a heart attack, take this test.)
What you can do about bad cholesterol
The artery-clogging process can start early in life. A 2008 autopsy study of adults ages 16 to 64 who died of non-heart-disease-related causes found that 83% had signs of heart disease and 8% had advanced disease. "We're seeing evidence of abnormality of blood vessels and obvious plaque in teenagers," says Dr. Nicholls.
Luckily, there are many things you can do to help prevent this process. "We know that lowering LDL cholesterol, the bad form, is clearly a good thing," says Dr. Nicholls. "The other thing we would highlight is the emerging role of HDL, or good cholesterol, the other player here."
Diet and exercise are critical for lowering LDL and raising HDL, notes Dr. Nicholls. (Click here for specific lifestyle changes that can lower heart disease risk.)
Cholesterol-lowering medication can also help, but you still need to watch your diet and exercise. "You can't just say, 'I'm being treated, so I can therefore not exercise and eat whatever I want,'" says Dr. Nicholls. "It doesn't work that way."
How can I reduce my cholesterol level?
Eat a healthy balanced diet
Eating lots of fruit, vegetables, and wholegrain is better than eating foods high in saturated or trans fats. You can replace saturated fats with the healthy monounsaturated and polyunsaturated fats such as olive, rapeseed or sunflower oils and spreads.
Choose foods that are high in soluble fibre such as oats, beans, pulses, lentils, nuts, fruits and vegetables. Soluble fibre can help lower cholesterol.
Do regular exercise
Regular physical activity can help increase your HDL cholesterol (the good type of cholesterol). Staying active is great way to keep your heart healthy.
Quit smoking
Quitting smoking can help to lower your cholesterol and improve your heart health.
Will I need to take medication?
Whether or not you need to take cholesterol-lowering medicine depends on your overall risk of cardiovascular disease.
Cholesterol-lowering medicines such as statins are prescribed for people who are at greatest overall risk of cardiovascular disease. If you have questions about your medicines, speak with your doctor or call our Heart Helpline on 0300 330 3311. You can also look at our publications for more information.
Will eating sterol-enriched foods help reduce my cholesterol level?
Although the effect varies between individuals, there is evidence to show that plant sterols and stanols can help to reduce LDL cholesterol by levels up to 10-15% when 2g per day is regularly consumed as part of a healthy balanced diet.
But whilst there is an expectation that this would lead to fewer heart attacks, no clinical trials have been undertaken to show this. Sterols and stanols have been added to certain foods, including margarines, spreads, soft cheeses and yoghurts.
Will eating too many eggs raise my cholesterol?
For most people, the amount of saturated fat they eat has much more of an impact on their cholesterol than eating foods that contain cholesterol, like eggs, liver, kidneys and shellfish. Unless you have been told otherwise by your doctor or dietician, if you like eggs, they can be included as part of a balanced and varied diet
