What Is Cholesterol?
We may associate cholesterol with fatty foods, but most of the waxy substance is made by our own bodies. The liver produces 75% of the cholesterol that circulates in our blood. The other 25% comes from food. At normal levels, cholesterol actually plays an important role in helping cells do their jobs. But cholesterol levels are precariously high in more than 100 million Americans.
Symptoms of High Cholesterol
High cholesterol does not cause any symptoms. But it does cause damage deep within the body. Over time, too much cholesterol may lead to a buildup of plaque inside the arteries. Known as atherosclerosis, this condition narrows the space available for blood flow and can trigger heart disease. The good news is high cholesterol is simple to detect, and there are many ways to bring it down.
Cholesterol Testing
People older than 20 should have their cholesterol levels checked at least once every five years. This is done with a simple blood test known as a fasting lipoprotein profile. It measures the different forms of cholesterol that are circulating in your blood after you avoid eating for 9 to 12 hours. The results show your levels of "bad" cholesterol, "good" cholesterol, and triglycerides.
"Bad" Cholesterol
Most of the cholesterol in the blood is carried by proteins called low density lipoproteins or LDL. This is known as the bad cholesterol because it combines with other substances to clog the arteries. A diet high in saturated fats and trans fats tends to raise the level of LDL cholesterol. For most people, an LDL score below 100 is healthy, but people with heart disease may need to aim even lower.
"Good" Cholesterol
Up to a third of blood cholesterol is carried by high-density lipoproteins or HDL. This is called good cholesterol because it helps remove bad cholesterol, preventing it from building up inside the arteries. The higher the level of HDL cholesterol, the better. People with too little are more likely to develop heart disease. Eating healthy fats, such as olive oil, may help boost HDL cholesterol.
Triglycerides
The body converts excess calories, sugar, and alcohol into triglycerides, a type of fat that is carried in the blood and stored in fat cells throughout the body. People who are overweight, inactive, smokers, or heavy drinkers tend to have high triglycerides, as do those who eat a very high-carb diet. A triglycerides score of 150 or higher puts you at risk for metabolic syndrome, which is linked to heart disease and diabetes.
Total Cholesterol
Total cholesterol measures the combination of LDL, HDL, and VLDL (very low density lipoprotein) in your bloodstream. VLDL is a precursor of LDL, the bad cholesterol. A total cholesterol score of under 200 is considered healthy in most cases. People who score in the "high" range have an increased risk of developing heart disease compared to those who score below 200.
Cholesterol Ratio
To calculate your cholesterol ratio, divide your total cholesterol by your HDL cholesterol. For example, a total score of 200 divided by an HDL score of 50 equals a cholesterol ratio of 4 to 1. Doctors recommend maintaining a ratio of 4 to 1 or lower. The smaller the ratio, the better. While this figure is useful in estimating heart disease risk, it's not as important in guiding treatment. Doctors look at total cholesterol, HDL cholesterol, and LDL cholesterol to determine treatment.
Cholesterol in Food
Cholesterol-rich foods, like eggs, shrimp, and lobster are no longer completely forbidden. Research shows that the cholesterol we eat has only a small effect on blood cholesterol levels for most people. A few people are "responders," whose blood levels spike up after eating eggs. But for most, saturated fat and trans fats are bigger concerns. Daily cholesterol limits are 300 mg for healthy people and 200 mg for those at higher risk. One egg has 186 mg of cholesterol.
Cholesterol Buster: Eat More Fiber
Diet changes offer a powerful way to fight high cholesterol. If you've ever wondered why some cereals claim to be heart-healthy, it's the fiber. The soluble fiber found in many foods helps reduce LDL, the bad cholesterol. Good sources of soluble fiber include whole-grain breads and cereals, oatmeal, fruits, dried fruits, vegetables, and legumes such as kidney beans.
Cholesterol Buster: Know Your Fats
No more than 35% of your daily calories should come from fat. But not all fats are equal. Saturated fats -- from animal products and tropical oils -- raise LDL cholesterol. Trans fats carry a double-whammy, boosting bad cholesterol, while lowering the good kind. These two bad fats are found in many baked goods, fried foods (doughnuts, french fries, chips), stick margarine, and cookies. Unsaturated fats may lower LDL when combined with other healthy diet changes. They're found in avocados, olive oil, and peanut oil.
Treatment: Supplements
Certain dietary supplements may also improve cholesterol levels. These include flaxseed oil, fish oil, and plant sterols, such as beta-sitosterol. Prescription niacin, a b-complex vitamin, has been found to raise good cholesterol while reducing bad cholesterol. Niacin found in ordinary supplements should not be used to lower cholesterol.
How Low Should You Go?
Many people are able to lower cholesterol levels through a combination of medication and lifestyle changes. But how low is low enough? For people with diabetes or a high risk of developing heart disease, an LDL score of less than 100 is desirable. If you already have heart disease or coronary artery disease, some doctors recommend reducing LDL to 70 or lower.
Can the Damage Be Undone?
It takes years for high cholesterol to clog the arteries with plaque. But there is evidence that atherosclerosis can be reversed, at least to some degree. Dean Ornish, MD, has published several studies showing that a low-fat vegetarian diet, stress management, and moderate exercise can chip away at the build-up inside the coronary arteries. Other research supports the idea that big drops in cholesterol can somewhat help open clogged arteries.
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