Preventing Heart Disease: Watch Your Cholesterol

At this very moment, your blood vessels are pulsing with the raw material that can cause a heart attack. Every drop of human blood contains cholesterol, a compound popularly referred to as a fat, which your body needs to form healthy cells and tissues. From birth on, your liver manufactures cholesterol, which is pushed out to the gut and reabsorbed back as part of a system for fat absorption. In addition, cholesterol in the food we eat gets absorbed into the body.

When too much cholesterol accumulates in the bloodstream, it can build up in the coronary arteries and block the flow of blood to the heart. But cholesterol doesn't have to be a threat. With a few healthy lifestyle changes -- and a little help from your doctor -- you can lower your cholesterol levels and slash your risks for heart attack.

What's a "healthy" cholesterol level?

When a doctor checks your cholesterol level, he or she will usually do a test that's called a lipid panel, which includes measuring your total cholesterol and some of the other fats that are in the blood. Unfortunately, there's no sharp cutoff point between healthy and unhealthy levels, but ideally, your total cholesterol should be below 170 milligrams per deciliter. Here's a chart from the American Health Association that summarizes their guidelines:

Looking at a breakdown of your levels of the different types of cholesterol can be even more helpful. The lipid panel can better evaluate your risk for heart disease by measuring your levels of the two major forms of cholesterol, LDL cholesterol and HDL cholesterol. In common lingo, LDL is called the "bad" cholesterol, and HDL is known as the "good" cholesterol. That's because LDL cholesterol is the substance that clogs arteries by delivering cholesterol to the cells and depositing it in the artery wall; HDL cholesterol, on the other hand, actually helps clear LDL cholesterol from the blood by trucking cholesterol back from the cells to the liver for disposal.

The basic goal is simple: You want to keep your LDL within the target level that's right for you. Your target level depends on your situation: In UC Health, Dr. Janice Huang, a general cardiologist with UCHealth Memorial Hospital in Colorado Springs, explains the new approach is often more individualized:

“Instead of setting a numeric cutoff for cholesterol for initiation of treatment, we are using risk instead,” she said. “For those at highest risk, the push is to get ‘bad’ cholesterol as low as possible, but really the marker is less than 70.”

You also want to keep your "good" HDL levels from getting too low. Your HDL should be at least 45 mg/dL, according to guidelines from the American Heart Association.. Since lower levels of "good" cholesterol appear to cause greater risk of heart disease in women, Johns Hopkins University recommends that women's HDL be at least 50 mg/dl. An HDL level of 60 mg/dL or higher is considered protective against heart disease.

How can I improve my cholesterol levels?

In many people, cholesterol levels are a reflection of lifestyle. In some cases, however, lifestyle may not account for the level of cholesterol in a person's blood, since that level is often influenced by "internal" factors such as genetics, liver disease or other conditions, or hormones. If you're born with a problem in regulating your internal cholesterol production (which is where most cholesterol comes from), you'll probably need medication to control it.

But high cholesterol levels are commonly associated with external factors such as excess weight, lack of exercise, a high-fat diet, and too much alcohol. The good news is that although unhealthy habits can wreak havoc on your cholesterol levels, a few positive changes can help bring them back under control. Here's a look at the best ways to lower cholesterol:

• If you smoke, stop. In addition to directly damaging your heart and arteries, cigarettes deplete your supply of HDL cholesterol.
• Eat a heart-healthy diet. If you're watching your cholesterol levels, you have to lower your intake of fat, especially saturated fat. Your body quickly turns saturated fat into LDL cholesterol. Do continue to eat healthy fats (olive oil, omega-3 fatty acids found in fish, and so on).
• The secret to lowering fat intake is to follow the advice we received from our parents and in turn give our children: watch what you put into your mouth. Before buying those tempting cookies, chips, and crackers in the grocery stories, read the product label: It will tell you many grams of saturated fat the food contains.
• Of course, a lot of fast food doesn't come with labels. If you want to find out how much saturated fat is found in a Big Mac, scone, or slice of pizza, check out the online version of Nutrition Action Health Healthletter (http://www.cspinet.org/nah/index.htm), which regularly analyzes the content of fast food and restaurant food.
• The journal reports, for example, that scones, cinnamon rolls, croissants, and other baked goods full of butter and cream often contain more saturated fat than a hamburger with cheese! A simple rule is that in all but a few instances, lowering saturated fat will also lower cholesterol intake (most "sat fats" are found in animal products such as meat, butter, lard, and milk).
• Another dangerous dietary villain is trans unsaturated fat or trans fat. Found in stick margarine, fried fast foods, and some snack foods like cookies, crackers, and donuts, trans fat gives your cholesterol level a double whammy: Not only does it increase your LDL cholesterol, but it also lowers your HDL cholesterol. A Harvard University study of more than 80,000 women suggested that replacing just 2 percent of trans fat calories with calories from healthier fats reduced the risk of heart disease by more than 50 percent. Read all processed food labels and look for "partially hydrogenated oils" -- that's the trans fats that you want to avoid. Look for products that contain olive oil instead. The AHA recommends limiting the amount of trans fats you consume to less than 1 percent of your daily calories -- in fact, there is no safe level of trans fats known to be safe, according to the National Academy of Sciences.
• You should also beware of eating too much dietary cholesterol. This is the type found in most animal products, especially egg yolks, meat, and seafood. Dietary cholesterol isn't quite as dangerous to your heart as saturated fat or trans fat, but you should still be cautious. The AHA recommends you eat no more than 300 mg of cholesterol each day. In practice, that means eating no more than three egg yolks a week and avoiding cholesterol-packed foods such as fried meats. Those with heart disease need to keep cholesterol levels to 200 mg and only two egg yolks a week.
• To fill the void left by fatty foods, you should eat plenty of whole grains and at least five to seven servings of fruits and vegetables every day. These foods protect the heart in several ways, including providing soluble fiber, a known cholesterol fighter. The AHA also recommends eating fish at least twice a week -- fatty fish such as salmon contain omega-3 fatty acids, or "good fats," which actually benefit the heart by lowering cholesterol. (If you don't like fish, you may want to take over-the-counter fish oil supplements containing omega-3s -- an option you can talk over with your physician.)
• If you're worried that it will be hard or complicated to go low-fat, consider this: Most people can cut their intake of artery-clogging saturated fat in half just by avoiding butter, margarine, fatty meats, and dairy products made from 2 percent or whole milk. (If you have to have margarine on your toast, use the soft kind rather than stick margarine, which may be high in trans fats.)
• It's also important to get moving. Regular workouts not only strengthen your heart but can also push your cholesterol levels in all the right directions. Your LDL cholesterol may drop, and your HDL cholesterol may rise. (LDL is primarily lowered by diet, and HDL is primarily increased by exercise, but we usually need to do both.) Staying active will also help you take off any extra pounds, an important step towards a healthy heart.

What can my doctor do to help?

Lifestyle changes can make a difference in cholesterol levels, but many people need medications to bring cholesterol completely under control. Drugs are especially important if you have other risk factors for heart disease or if you already have heart trouble. Your doctor can also help you track your cholesterol.

What's the right age to start thinking about cholesterol?

Heart attacks usually strike people in their 40s and older, but the clogging process starts decades earlier. Researchers at the University of Texas examined the arteries of 3,000 people aged 15 to 34 who died from an accident, homicide, or suicide. As reported in the American Journal of Clinical Nutrition, many of these people already had clumps of cholesterol in their arteries. Not surprisingly, the victims with the highest cholesterol levels in their blood also had the most serious buildup in their arteries.

The researchers concluded that the teen-age years are an excellent time to start protecting the heart. But don't worry -- even if your teens are a distant memory, it's not too late to make some healthy lifestyle changes to bring your cholesterol count under control. When it comes to preventing heart attacks, a late start is much better than no start at all.

References

National Institutes of Health. "Update on Cholesterol Guidelines: More-Intensive Treatment Options for Higher Risk Patients."

American Heart Association. Cholesterol.

The American Heart Association. For Professionals: Cholesterol levels.

American Heart Association. What Are Healthy Levels of Cholesterol?

McGill, H. et al. Origin of atherosclerosis in childhood and adolescence. American Journal of Clinical Nutrition. 2000; 72 (supp.): 1307-1315S.