The Skinny on Cholesterol

1. Cholesterol Levels Slideshow Pictures
2. Lowering Cholesterol Slideshow Pictures
3. Take the Cholesterol Quiz

Here's what you need to know to keep yours low

By Kathleen Zelman, MPH, RD, LD
WebMD Weight Loss Clinic - Expert Column

It can be a nightmare, trying to sort through all the news on good cholesterol, bad cholesterol, saturated fats, trans fats, and all those other hard-to-pronounce fats.

Fear no more. Read on for a primer on everything you need to know about cholesterol (Call it Cholesterol 101).

The Basics

Cholesterol is a type of waxy substance (called a lipid) that your body needs for many functions, including the production of new cells.

You get cholesterol from two sources: Internally, your body makes cholesterol; and externally, you get cholesterol from foods you eat.

Though it seems logical that foods containing cholesterol would raise levels of cholesterol in your blood, the worst dietary culprits are actually foods high in saturated fats (mostly from animal sources) and/or trans fats (often found in commercially prepared products).

Here are a few examples of foods high in those two types of fat:

Think of cholesterol as sort of like a chocolate M&M in the blood: the center is the cholesterol, and the outer shell is a protein "carrier" that transports the molecule through the blood. The molecule it carries is called a lipoprotein, and it is classified as either a low-density lipoprotein (LDL), the so-called "bad" cholesterol, or high-density (HDL), the "good" cholesterol.

What makes them "good" or "bad" is determined by the amount of cholesterol center and protein shell. The good cholesterol has more protein and less cholesterol; the bad cholesterol has more cholesterol and less protein. The composition of the good cholesterol molecule prevents the buildup of cholesterol in your arteries. But the bad cholesterol molecule can lead to buildup, and eventual blockage, of your arteries.

The Problem With High Cholesterol

If your diet is too high in saturated and/or trans fats, or if you have an inherited condition, the cholesterol in your blood can reach dangerously high levels. Other factors, like diabetes and hypothyroidism, can also raise your blood cholesterol.

High levels of cholesterol can put you at risk for a host of life-threatening cardiovascular (heart and circulatory system) diseases. To reduce the risk of these diseases, your goal is to lower total cholesterol and to aim for high levels of good cholesterol and low levels of bad cholesterol. And one of the best routes to a healthier heart is a cholesterol-lowering diet.

Your doctor will determine if you are a candidate for cholesterol-lowering medication based on your blood cholesterol profile. But even those on medication can benefit from lifestyle changes such as a healthy diet, regular exercise, weight loss, and smoking cessation.

Indeed, one of the best ways to prevent and control high cholesterol is by eating healthy, exercising, and losing weight (if you're too heavy). The American Heart Association (AHA) recommends a diet that includes plenty of fruits, vegetables, whole grains, low-fat dairy, and lean protein, with a limit of 300 mg of cholesterol per day, and less than 30% of its calories from fat. The WebMD Weight Loss Clinic recommends a heart-healthy diet to all its members.

To ensure heart health and help lower cholesterol, here are some recommendations about foods and nutrients to include in your diet:

• Fiber. Fiber is not only important for lowering your cholesterol, it can also help you lose weight. Both soluble fiber (found in oats and beans) and insoluble fiber (in fruits, vegetables, fruits and grains) can help lower cholesterol. Fiber binds and helps carry excess cholesterol from your body. The Institute of Medicine recommends 21-38 grams of fiber per day for adults. Start your day with a bowl of oatmeal topped with fresh fruit to get a jump on meeting your daily requirement.
• Soy. A daily 25 grams of soy protein can help lower cholesterol by decreasing its production in the liver and by removing "bad" cholesterol from the blood. In fact, the FDA has decided to allow soy-rich food products to carry labels touting their cholesterol lowering benefit. Read the labels of soy products -- like soymilk, soy yogurt, tofu, soy nuts, edaname -- to make sure you are getting enough to help lower cholesterol levels.
• Sterols and stanols. Plant substances called sterols and stanols can interfere with cholesterol absorption and reduce your total cholesterol levels. The main way to get them in your diet is in special margarines like Take Control and Benecol. Minute Maid also promises an orange juice that will contain these cholesterol-lowering substances. Read the labels to determine if you're getting enough to achieve the desired effect.
• Monounsaturated and polyunsaturated fats. You know these as the "good fats" found in foods like corn oil, soybean oil, sunflower oil, olive oil, canola oil, avocados, nuts, and seeds. Choosing these fats over saturated and trans fats will help lower your cholesterol level. Keep in mind that you should limit total fats in your diet -- but when you do have them, opt for these healthier choices.
• Red wine. Music to your ears? It's true: a glass of red wine is believed to help lower cholesterol levels. Red wines contain substances called saponins that can bind to cholesterol and prevent its absorption into the bloodstream. So follow the Mediterranean lifestyle and enjoy a glass with dinner once in a while. (Just be careful not to overdo it.)
• Omega-3 fatty acids. These fatty acids make the blood less likely to form clots that can cause heart disease. How to get them? The American Heart Association (AHA) recommends that healthy adults consume two servings a week of fish, especially fatty fish like salmon and lake trout. Other sources of omega-3s are nuts, seeds, soybeans, canola, walnut, flaxseeds, and oils made from these products.
• Eggs. In 2002, the AHA revised its recommendation on eggs, after decades of research showed that they are not the villains in heart disease. The AHA no longer makes a recommendation about how many egg yolks you should eat per week, as long as your average daily intake of cholesterol is less than 300 mg. Eggs are powerhouses of nutrition, an excellent and inexpensive source of protein. Most healthy adults can enjoy one daily.