Friday, October 19, 2007

Heart

 

 

Heart

Cholesterol, LDL, HDL and Triglycerides

Facts about cholesterol:

Cholesterol is a waxy substance that can be found in all parts of your child’s body. It aids in the production of cell membranes, some hormones, and vitamin D. The cholesterol in blood comes from two sources: the foods your child eats and his/her liver. However, your child’s liver makes all of the cholesterol your child’s body needs.

Cholesterol and other fats are transported through the blood stream in the form of round particles called lipoproteins. The two most commonly known lipoproteins are low-density lipoproteins (LDL) and high-density lipoproteins (HDL).

What is LDL (low-density lipoprotein) cholesterol?

This type of cholesterol is commonly called “bad” cholesterol. It can contribute to the formation of plaque build-up in the arteries, known as atherosclerosis.

LDL levels should be low. To help lower LDL levels, help your child to:

  • avoid foods high in saturated fat, dietary cholesterol, and excess calories.
  • increase exercise.
  • maintain a healthy weight.

What is HDL (high-density lipoprotein) cholesterol?

This type of cholesterol is known as “good” cholesterol, and is a type of fat in the blood that helps to remove cholesterol from the blood, preventing the fatty build up and formation of plaque.

HDL should be as high as possible. It is often possible to raise HDL by:

  • exercising for at least 20 minutes three times a week.
  • avoiding saturated fat intake.
  • decreasing body weight.

For some children, medication may be needed. Because raising HDL can be complicated, you should work with your child’s physician on developing a therapeutic plan.

 

Checking blood cholesterol levels:

A cholesterol screening is an overall look at, or profile of, the fats in the blood.

Physicians in the past felt that children were at little risk for developing high cholesterol levels and other risk factors for heart diseases affecting the coronary arteries and blood vessels until later in life. However, many physicians now realize that children are increasingly at risk for having high blood cholesterol levels as a result of one, or more of the following:
  • Sedentary lifestyles (playing video games and watching TV instead of participating in vigorous exercise).
  • High-fat junk food and fast-food diets.
  • Obesity.
  • Family history of high cholesterol levels.

Children and adolescents with high cholesterol are at higher risk for developing heart disease as adults. Many physicians are recognizing that keeping blood cholesterol levels in normal ranges throughout one’s lifetime may be of great benefit in reducing the likelihood of developing coronary artery disease and high blood pressure.

Cholesterol testing for children:

The National Heart, Lung, and Blood Institute (NHLBI), a division of the National Institutes of Health, recommends that cholesterol testing begin at age 2 for any child who has the following:
  • At least one parent who has been found to have high blood cholesterol (240 milligrams or greater).
  • A family history of early heart disease (before age 55 in a parent or grandparent).

The NHLBI also recommends that children who have demonstrated risk factors, such as obesity, should have cholesterol and other lipids tested periodically by their physicians.

A full lipid profile shows the actual levels of each type of fat in the blood: LDL, HDL, triglycerides, and others. Consult your child’s physician regarding the timeliness of this test.

What is a healthy blood cholesterol level?

Blood cholesterol is very specific to each individual. A full lipid profile can be an important part of your child’s medical history, and important information for your child’s physician to have. In general, healthy levels are as follows:
  • LDL - less than 130 milligrams (mg).
  • HDL - greater than 35 mg (less than 35 mg puts your child at higher risk for heart disease).

The NHLBI recommends the following guidelines for cholesterol levels in children and teenagers (ages 2 to 19) from families with high blood cholesterol or early heart disease:

 

Total cholesterol 

LDL-cholesterol

Acceptable 

Less than 170 mg 

Less than 110 mg 

Borderline

170 to 199 mg 

110 to 129 mg 

High

200 mg or greater

130 mg or greater

 

Statistics about cholesterol:

Elevated cholesterol is a risk for many Americans. Consider these statistics:
  • About 30 percent of American adults have total cholesterol levels between 200 and 239.
  • More than 25 percent of the adult US population has blood cholesterol levels greater than 240, which is considered high risk.
  • Up to one-third of young adults have a blood cholesterol level higher than 200 mg.
  • According to the American Heart Association, high blood cholesterol that runs in families will affect the future of an unknown (but probably large) number of children.

What are triglycerides?

Triglycerides are another class of fat found in the bloodstream. The bulk of your child’s body fat tissue is in the form of triglycerides.

The link between triglycerides and heart disease is under clinical investigation. However, many children with high triglyceride levels also have other risk factors such as high LDL levels or low HDL levels.

What causes elevated triglyceride levels?

Elevated triglyceride levels may be caused by medical conditions such as diabetes, hypothyroidism, kidney disease, or liver disease. Dietary causes of elevated triglyceride levels may include obesity and high intakes of fat, alcohol, and concentrated sweets.

Question:
I have wondered about that too - but from another angle. Since you eat so much fat on a ketogenic diet, is it gonna hurt you down the road? I realise its fairly short periods of high fat, but still… I thought I had read someting by Lyle when he was doing the BodyOpus diary about it not being a problem, but I can’t remember, and haven’t bothered to search for it - maybe someone else can chime in here?

Answer:
Depends on the relative amounts of the types of fats you eat, right! Saturated vs unsaturated. Hydrogenated vs non-hydrogenated. Mono- vs poly. Essential vs non. etc. That is why EFAs in the form of flax/borage or fish oils are favored by some camps - less saturated fat, more fats that change cholesterol (LDL/HDL) ratio towards a more CV-healthy one. Hydrogenated oils should be avoided; hard at room temp = hard(-er) to break down (in room and in body). Lots more to it, bio-chemically/chemically of course. The LDL HDL cholesterol ratio is more important than individual levels of HDL cholesterol and LDL cholesterol. However, recent heart Foundation recommendation is that irrespective of the ratio, one should try to reduce the LDL cholesterol. Total cholesterol to HDL cholesterol ratio (Total / HDL) is found by dividing total cholesterol by HDL cholesterol. The total cholesterol is the sum of HDL, LDL, and the VLDL. Total/HDL Ratio = [Total Cholesterol/HDl Cholesterol] This ratio becomes high when the total cholesterol increases and HDL cholesterol decreases. Low ratio indicates lower risk of heart attack, while high ratio indicates higher risk. The total/HDL becomes low for low total cholesterol and high HDL cholesterol values. The safe total/HDL ratio is less than 4. Total/HDL is more commonly obtained because the total cholesterol is easier and cheaper to obtain. LDL to HDL cholesterol ratio (LDL/HDL) is found by diving LDL cholesterol by HDL cholesterol values. LDL/HDL Ratio = [LDL Cholesterol / HDL Cholesterol] The LDL/HDL ratio is more important ratio than total cholesterol/HDL because LDL is a measure of bad cholesterol and HDL is a measure of good cholesterol. LDL/HDL is therefore an accurate measure of heart disease although it is costly to measure LDL cholesterol. The risk levels of different values of LDL/HDL ratios are: Risk Level LDL/HDL Ratio Low risk 3.3 - 4.4 Average risk 4.4 - 7.1 Moderate risk 7.1 - 11.0 High risk 11Question:

I have wondered about that too - but from another angle. Since you eat so much fat on a ketogenic diet, is it gonna hurt you down the road? I realise its fairly short periods of high fat, but still… I thought I had read someting by Lyle when he was doing the BodyOpus diary about it not being a problem, but I can’t remember, and haven’t bothered to search for it - maybe someone else can chime in here?

 

Answer:

Depends on the relative amounts of the types of fats you eat, right! Saturated vs unsaturated. Hydrogenated vs non-hydrogenated. Mono- vs poly. Essential vs non. etc. That is why EFAs in the form of flax/borage or fish oils are favored by some camps - less saturated fat, more fats that change cholesterol (LDL/HDL) ratio towards a more CV-healthy one. Hydrogenated oils should be avoided; hard at room temp = hard(-er) to break down (in room and in body). Lots more to it, bio-chemically/chemically of course. The LDL HDL cholesterol ratio is more important than individual levels of HDL cholesterol and LDL cholesterol. However, recent heart Foundation recommendation is that irrespective of the ratio, one should try to reduce the LDL cholesterol. Total cholesterol to HDL cholesterol ratio (Total / HDL) is found by dividing total cholesterol by HDL cholesterol. The total cholesterol is the sum of HDL, LDL, and the VLDL. Total/HDL Ratio = [Total Cholesterol/HDl Cholesterol] This ratio becomes high when the total cholesterol increases and HDL cholesterol decreases. Low ratio indicates lower risk of heart attack, while high ratio indicates higher risk. The total/HDL becomes low for low total cholesterol and high HDL cholesterol values. The safe total/HDL ratio is less than 4. Total/HDL is more commonly obtained because the total cholesterol is easier and cheaper to obtain. LDL to HDL cholesterol ratio (LDL/HDL) is found by diving LDL cholesterol by HDL cholesterol values. LDL/HDL Ratio = [LDL Cholesterol / HDL Cholesterol] The LDL/HDL ratio is more important ratio than total cholesterol/HDL because LDL is a measure of bad cholesterol and HDL is a measure of good cholesterol. LDL/HDL is therefore an accurate measure of heart disease although it is costly to measure LDL cholesterol. The risk levels of different values of LDL/HDL ratios are: Risk Level LDL/HDL Ratio Low risk 3.3 - 4.4 Average risk 4.4 - 7.1 Moderate risk 7.1 - 11.0 High risk 11

 

LDL and HDL Cholesterol: What’s Bad and What’s Good?  

Cholesterol can’t dissolve in the blood. It has to be transported to and from the cells by carriers called lipoproteins. Low-density lipoprotein, or LDL, is known as “bad” cholesterol. High-density lipoprotein, or HDL, is known as “good” cholesterol. These two types of lipids, along with triglycerides and Lp(a) cholesterol, make up your total cholesterol count, which can be determined through a blood test. 

LDL (Bad) Cholesterol
When too much LDL (bad) 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 narrow the arteries and make them less flexible.  This condition is known as atherosclerosis. If a clot forms and blocks a narrowed artery, heart attack or stroke can result.

HDL (good) Cholesterol
About one-fourth to one-third of blood cholesterol is carried by high-density lipoprotein (HDL). HDL cholesterol is known as “good” cholesterol, because high levels of HDL seem to protect against heart attack. Low levels of HDL (less than 40 mg/dL) also increase the risk of heart disease. 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 that HDL removes excess cholesterol from arterial plaque, thus slowing its buildup.

Triglycerides
Triglyceride is a form of fat made in the body. Elevated triglycerides can be due to overweight/obesity, physical inactivity, cigarette smoking, excess alcohol consumption and a diet very high in carbohydrates (60 percent of total calories or more). People with high triglycerides often have a high total cholesterol level, including a high LDL (bad) level and a low HDL (good) level. Many people with heart disease and/or diabetes also have high triglyceride levels.

Lp(a) Cholesterol
Lp(a) is a genetic variation of LDL (bad) cholesterol. A high level of Lp(a) is a significant risk factor for the premature development of fatty deposits in arteries. Lp(a) isn’t fully understood, but it may interact with substances found in artery walls and contribute to the buildup of fatty deposits.

Biochemistry Group, Heart Research Institute, Sydney, New South Wales, Australia.

 

The reaction of phospholipid hydroperoxide glutathione peroxidase (PHGPx) and Ebselen with phospholipid and cholesterylester hydroperoxides associated with HDLox and LDLox was investigated using specific HPLC assays for the hydroperoxides of phosphatidylcholine (PCOOH) and cholesteryllinolate (Ch18:2-OOH) and for cholesteryllinolate hydroxides (Ch18:2-OH). HDLox and LDLox were formed from the corresponding isolated native lipoproteins by controlled and limited oxidation initiated by aqueous peroxyl radicals. Incubation of HDLox or LDLox in the presence of PHGPx/GSH or Ebselen/GSH resulted in rapid degradation of both classes of lipid hydroperoxides, with equimolar amounts of Ch18:2-OH formed from Ch18:2-OOH. No pronounced differences were observed between PCOOH and Ch18:2-OOH in terms of substrate specificity, whereas HDLox-associated PCOOH and Ch18:2-OOH appeared to be slightly better substrates for PHGPx/GSH as compared to those in LDLox. Also, Ch18:2-OOH associated with HDLox but not LDLox were reduced by Ebselen or GSH alone. These in vitro findings indicate that the enzymatic PHGPx/GSH and the nonenzymatic Ebselen/GSH systems can efficiently reduce hydroperoxides of phospholipids and cholesterylesters associated with intact lipoproteins.

High Cholesterol

With increased awareness of the factors that lead to the high risk of heart disease, consumers have taken the matter out of medical doctor’s hands and into their own.

Conscious home-cooking has taken the place of fast foods and convenience items. A diet that consists of whole-grains, grilled meats, fish, salads, vegetables and small servings of fruit is finding its way back into the mainstream as consumers are scared straight. Instead of bacon and eggs and toast for breakfast, awareness towards oatmeal and cereal  where the first ingredient listed is whole grain and not sugar based is being considered, all in an attempt to stop high cholesterol.

This article will help you navigate the path known to many as the Cholesterol Confusion.

What is high cholesterol?

It is important to note that there are several types of cholesterol and one type is not harmful. In fact, it is referred to as the “good” cholesterol HDL (high-density lipoproteins).

One would assume that when they are talking about High Cholesterol, they must mean HDL, but in fact High Cholesterol is caused by LDL (low-density lipoproteins) confused yet? Let us explain:

About 70% of the cholesterol in our blood (produced mainly from our liver) is LDL or “bad cholesterol.” Cholesterol is necessary for the health of our living cells, however when you get into high levels of cholesterol you are at an increased risk for heart disease.

Cholesterol moves (with help) from your liver, through your blood, into the cells and eventually returns back to your liver. Although cholesterol moves in your blood, it moves within a fatty protein that envelops it. Our cells need this cholesterol, but when we, by lifestyle or diet add to our system more cholesterol then the body can handle, or through a genetic trait, some people’s bodies can’t read the signals when there is too much cholesterol in the blood and the body keeps making more.

HDL’s clean out the LDL’s by removing the bad cholesterol that is forming on the artery walls and shuttling it back into the liver. LDL’s also helps the liver ferry out the waste in bile. But when these levels are not balanced, that is when we run into trouble.

How do I find out that I have high cholesterol?

Talk to your doctor about a cholesterol screening. The rule of thumb is that after your 20th birthday, you should have a cholesterol screening every five years.

This requires you to fast 9-12 hours prior to the test. They draw blood and test it for LDL, HDL, triglyceride levels and then total cholesterol.

  • For the LDL level, or bad cholesterol- less than 100 mg/dL is good.
  • Anything over 130 mg/dL is considered high cholesterol.
  • HDL or good cholesterol 60mg/dL.
  • Under 40 mg/dL high risk for heart disease.
  • Triglyceride values less than 150 mg/dL
  • Total Cholesterol below 200 mg/dL

Cholesterol is not a cause of heart disease or stroke, but it is a pointer to the disease. The culprit is Homocysteine, a protein produced in the blood during the metabolic process when an amino acid meets and is joined by another amino acid containing sulfur. When this level becomes higher than the body can tolerate the artery walls get attacked. The walls are destroyed and a plaque builds up the wall. This plaque is a cholesterol magnet, and cholesterol forms on top of this plaque, eventually building barriers that block arteries or close them off altogether. When LDL and HDL plaque is formed the LDL is the stronger of the two, and it knows out the HDL causing heart attacks, strokes, and other cardiovascular disease.

 

 

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