The buzz about high cholesterol has faded to a low hum in 2009 as other health topics grab the headlines. But blood cholesterol and its role in heart disease and stroke still command attention in medical circles. Despite a decline in the number of deaths from heart attacks, cardiovascular disease still kills more people than all cancers combined and is the No. 1 cause of death and disability in the United States. One in every six Americans ages 20 or older has high cholesterol and is at heightened risk of heart disease because of it. That's the bad news.
The good news is that the threat of cardiovascular disease could be cut in half by a combination of effective public health efforts and individual action to reduce major risk factors, like high cholesterol and type 2 diabetes.
Healthy dietary choices and regular exercise are among the most effective weapons in the fight against high cholesterol. So are the cholesterol-lowering drugs known as statins, which many people take to keep cholesterol in check. But statins aren't a magic bullet. They don't work for everybody, and some people can't tolerate them. Other people have heart attacks even though they're taking medications.
In 2009, the search for alternative, genetic, and supplementary therapies is in full swing, and will continue to drive treatment in the years ahead. In the interim, there are resources you can use to find out if your cholesterol levels are in a healthy range, and what you can do if they're not. The National Cholesterol Education Program (NCEP) guidelines (see "Cholesterol in the body") are a good place to start. So is this report.
In these pages, you'll find information on what your cholesterol levels should be and the best ways to bring them in line with 2009 standards. You'll learn about cholesterol tests that go well beyond the standard lipid check; scientific findings on Vytorin, Zetia, and other medications; plus details on treatments based on the latest 2009 scientific evidence. High cholesterol is a risk factor you can do something about. This report can help you safeguard your health and make informed decisions about what to do and how to do it.
Mason W. Freeman, M.D.
Cholesterol in the body
Cholesterol belongs to the class of compounds known as lipids, or fats. If you held an ounce of cholesterol in your hand, you would see a whitish-yellow waxy powder that resembles very fine scrapings from a candle. For humans and other animals, cholesterol and other lipids are as necessary as light and air. Our bodies need them to survive. Cholesterol is the main component of cell membranes and structures, a kind of building block for body tissues. Certain glands use it to produce corticosteroids and hormones, including testosterone and estrogen. It helps the liver make the bile acids we need to digest and absorb fats, and it's an important precursor to vitamin D.
In fact, cholesterol is so essential, your body makes about 75% of it on its own. You provide the rest from the foods you eat. Nutritionists use the words "dietary cholesterol" to distinguish the kind you consume from the kind your body produces. If you're an adult who eats only 200 to 300 milligrams (mg) of cholesterol a day (one egg yolk has about 200 mg), your body will make an additional 800 mg a day, most of it in the liver and some in the intestine. So even if you were able to eliminate every morsel of cholesterol from your diet, your liver would make enough to meet your body's needs, assembling it from such raw materials as fats, sugars, or proteins.
All those burgers
What goes in doesn't all come out. Years of eating fatty foods like high-fat meats, cheeses, and pastries line your arteries with cholesterol-laden plaque — a heart attack or stroke waiting to happen.
HDLs, LDLs, and other lipid particles
Your bloodstream delivers a constant supply of cholesterol and other lipids to cells throughout your body. This process is not a simple one. Lipids and blood are like oil and water; they don't mix. If your liver or intestine simply dumped lipids into your blood, they would congeal into unusable globs.