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The lowdown on Cholestrol
Cholesterol is an important part of a healthy body. Too much of a good thing leads to big trouble.

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As many of you know cholesterol screening is performed during a yearly physical exam. This is because high cholesterol values are associated with heart disease and stroke, two common causes of death and disability.


 



 

Men aged 35 and older and women aged 45 and older should have their cholesterol checked periodically. You should have your cholesterol checked often if you:

  • Have already had a heart attack
  • Are a man 45 years of age or older
  • Have a father or brother who had heart disease before 55
  • Are a woman who is going through menopause or has completed menopause
  • Have a mother or sister who had heart disease before 65
  • Smoke cigarettes
  • Have high blood pressure or diabetes
  • Are very overweight
     

What is Cholesterol?

Cholesterol is a soft, waxy substance found among the fats in the bloodstream and in all your body's cells. It's an important part of a healthy body because it's used to form cell membranes, some hormones and is needed for other functions. But a high level of cholesterol in the blood — hypercholesterolemia — is a major risk factor for coronary heart disease, which leads to heart attack.

Cholesterol and other fats can't dissolve in the blood. They have to be transported to and from the cells by special carriers called lipoproteins. There are several kinds, but the ones to focus on are low-density lipoprotein (LDL) and high-density lipoprotein (HDL).

Low-density lipoprotein (LDL) is the major cholesterol carrier in the blood. If too much LDL cholesterol circulates in the blood, it can slowly build up in the walls of the arteries feeding 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. A clot (thrombus) that forms near this plaque can block the blood flow to part of the heart muscle and cause a heart attack. If a clot blocks the blood flow to part of the brain, a stroke results. A high level of LDL cholesterol (160 mg/dL and above) reflects an increased risk of heart disease. If you have heart disease, your LDL cholesterol should be less than 100 mg/dL. That's why LDL cholesterol is called "bad" cholesterol. Lower levels of LDL cholesterol reflect a lower risk of heart disease.

About one-third to one-fourth of blood cholesterol is carried by HDL. Medical experts think HDL tends to carry cholesterol away from the arteries and back to the liver, where it's passed from the body. Some experts believe HDL removes excess cholesterol from plaques and thus slows their growth. HDL cholesterol is known as "good" cholesterol because a high HDL level seems to protect against heart attack. The opposite is also true: a low HDL level (less than 40 mg/dL) indicates a greater risk. A low HDL cholesterol level also may raise stroke risk.

People get cholesterol in two ways. The body — mainly the liver — produces varying amounts, usually about 1,000 milligrams a day. Your diet also influence cholesterol levels. Foods from animals (especially egg yolks, meat, poultry, fish, seafood and whole-milk dairy products) contain it. Foods from plants (fruits, vegetables, grains, nuts and seeds) don't contain cholesterol.

Typically the body makes all the cholesterol it needs, so people don't need to consume it. Saturated fatty acids are the main culprit in raising blood cholesterol, which increases your risk of heart disease. Trans fats also raise blood cholesterol. But dietary cholesterol also plays a part. The average American man consumes about 337 milligrams of cholesterol a day; the average woman, 217 milligrams.

Some of the excess dietary cholesterol is removed from the body through the liver. Still, the American Heart Association recommends that you limit your average daily cholesterol intake to less than 300 milligrams. If you have heart disease, limit your daily intake to less than 200 milligrams. Still, everyone should remember that by keeping their dietary intake of saturated fats low, they can significantly lower their dietary cholesterol intake. Foods high in saturated fat generally contain substantial amounts of dietary cholesterol.

Knowing which fats raise LDL cholesterol and which ones don't is the first step in lowering your risk of heart disease. Saturated fat, trans-fatty acids and dietary cholesterol raise blood cholesterol. Monounsaturated fats and polyunsaturated fats don't. Some studies suggest they might even help lower LDL cholesterol slightly when eaten as part of a low-saturated-fat diet.

Saturated fat is found mostly in foods from animals and some plants.

Foods from animals — These include beef, beef fat, veal, lamb, pork, lard, poultry fat, butter, cream, milk, cheeses and other dairy products made from whole milk. These foods also contain dietary cholesterol.

Foods from plants — These include coconut oil, palm oil and palm kernel oil (often called tropical oils), and cocoa butter.

Hydrogenated fats (“trans fats”) are also culprits. During food processing, fats may undergo a chemical process called hydrogenation. This is common in margarine and shortening. These fats also raise blood cholesterol. Use hydrogenated fats only if they contain no more than two grams of saturated fat per tablespoon. The saturated fat content of most margarines and spreads is printed on the package or Nutrition Facts label.

"Eat a low-fat, low-cholesterol diet." Unfortunately, this simple message is now largely out of date. Detailed research -much of it done at Harvard - shows that the total amount of fat in the diet, whether high or low, isn't really linked with disease. What really matters is the type of fat in the diet. Bad fats increase the risk for certain diseases and good fats lower the risk. The key is to substitute good fats for bad fats. And cholesterol in food? Although it is still important to limit the amount of cholesterol you eat, especially if you have diabetes, dietary cholesterol isn't nearly the villain it's been portrayed to be. Cholesterol in the bloodstream is what's most important.

The biggest influence on blood cholesterol level is the mix of fats in the diet. As a result:

  • Saturated fat intake should be less than10 % of calories.
  • Polyunsaturated fat intake should be up to 10 % of calories.
  • Monounsaturated fat can make up to 15 to 20 % of total calories.
  • Total fat intake should be less than 30 % of total calories.
  • Cholesterol intake should be 200 milligrams per day



WHAT IS YOUR UPPER LIMIT ON FAT FOR THE CALORIES YOU CONSUME PER DAY?


Total Calories per Day / Saturated Fat Grams / Total Fat Grams
___________________________________________________

1,600------------------18 or less----------------53
2,000------------------20 or less----------------65
2,200------------------24 or less----------------73
2,500------------------25 or less----------------80
2,800------------------31 or less----------------93

Regular physical activity increases HDL cholesterol in some people. Higher HDL cholesterol is linked with a lower risk of heart disease. Physical activity can also help control weight, diabetes and high blood pressure. Aerobic physical activity raises your heart and breathing rates. Regular moderate to intense physical activity such as brisk walking, jogging and swimming also condition your heart and lungs. Physical inactivity is a major risk factor for heart disease. Even moderate-intensity activities, if done daily, help reduce your risk. Examples are walking for pleasure, gardening, yard work, housework, dancing and prescribed home exercise.

Tobacco smoke is one of the six major risk factors of heart disease that you can change or treat. Smoking lowers HDL cholesterol levels and increases the tendency for blood to clot.

In some studies, moderate use of alcohol is linked with higher HDL cholesterol levels. However, because of other risks, the benefit isn't great enough to recommend drinking alcohol if you don't do so already. If you drink, do so in moderation. People who consume moderate amounts of alcohol (an average of one to two drinks per day for men and one drink per day for women) have a lower risk of heart disease than nondrinkers. However, increased consumption of alcohol brings other health dangers, such as alcoholism, high blood pressure, obesity, stroke, cancer, suicide, etc. Given these and other risks, the American Heart Association cautions people against increasing their alcohol intake or starting to drink if they don't already do so. Consult your doctor for advice on consuming alcohol in moderation.

Please stay healthy and, as always, warmest regards,

Andrea



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Andrea Ruman, M.D. - Doctor of Internal Medicine
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Dr. Andrea Ruman: Female medical doctor, physician, internist for Marina Del Rey, Santa Monica, West Los Angeles (LA), and Culver City in California. Specialties include women's health (including physical examinations, pelvic exams and pap smears), weight loss support and preventive medicine.