Cholesterol is a natural substance that serves as a building block for cells and hormones. A certain amount is good for you. But, excess cholesterol can stick to the walls of vessels, making it harder for blood to move through them. Sometimes cholesterol blocks an artery. Then, the body part served by the artery cannot receive needed nutrients or oxygen. A heart attack can occur if an artery is blocked in the heart. If the blockage is in the brain, a stroke can result.
The liver makes most of the cholesterol in your body. A small amount also comes from certain foods, such as meat, dairy products (such as butter, whole milk, and cheese), and eggs. The amount of cholesterol in your body depends partly on your diet and partly on factors passed on from your parents (heredity).
What It Does
The fat in the foods you eat is digested and sent to the liver. The liver then changes the fat into lipoproteins. Lipoproteins are made of cholesterol, other fats, and protein. Lipoproteins carry fat through your blood vessels for use or storage in other parts of the body. Without them, fat could not travel through the bloodstream. This is because blood is mainly made of water—and fat and water do not mix.
There are three kinds of lipoproteins: VLDL (very–low–density lipoprotein, LDL (low–density lipoprotein) and HDL (high–density lipoprotein).
Each lipoprotein has a job to do. First, the liver changes the fat into VLDL, which carries the fat through your blood vessels to your fat tissue. After the VLDL drops off some of the fat, but not its cholesterol, it becomes LDL. It is LDL, sometimes called “bad cholesterol,” that can stick to the sides of blood vessels and even block arteries in vital organs such as the heart and brain.
HDL, sometimes called “good cholesterol,” keeps cholesterol from building up in artery walls. It does this by picking it up and taking it back to the liver. Then, the liver breaks it down so that it can be passed out of the body. A high level of HDL helps to lower the level of LDL. The goal of a healthy diet is to keep HDL high and LDL low.
What Happens When You Eat Too Much Fat?
A high–fat diet causes too much LDL, or bad cholesterol, in the bloodstream. This can make it hard for the HDL, or good cholesterol, to do its job.
Too much cholesterol can clog blood vessels. This causes deposits that form a substance called plaque. Over the years, the plaque narrows and hardens the arteries. This is called atherosclerosis.
High blood cholesterol has no symptoms. A simple blood test can show whether your level is normal. Knowing how to keep a healthy cholesterol level through diet, exercise, and regular checkups will help you to lower your risk of cardiovascular disease.
The amount of total cholesterol in your blood can be found by a simple blood test. Total cholesterol is the sum of LDL and HDL. In general, the lower your cholesterol level, the better.
A lipoprotein analysis may be done if the test shows that your cholesterol level is more than 200 mg/dL. This test breaks down the total cholesterol into LDL and HDL. Your level of VLDL may be tested, too.
Even if your cholesterol level is less than 200 mg/dL, you may need a lipoprotein analysis if you have one of the following risk factors: history of parent, brother, or sister with a cholesterol level of 240 mg/dL or higher, history of brother, sister, parent, or grandparent with heart disease before age 55, diabetes and cigarette smoking.
You also may have your triglycerides tested. They are a type of fat. Recommended levels of cholesterol and triglycerides are shown in the table. LDL cholesterol is key. When it’s too high, your risk of heart attack, stroke, or other cardiovascular disease is increased.
All women aged 45 years and older should have their cholesterol levels checked every 5 years.
Women with any of the following risk factors may need to be tested more often and at a younger age: have had high cholesterol or heart disease, have a family history of high cholesterol or heart disease, smoke and/or have diabetes.
Risk Factors for Atherosclerosis
The amounts of total and LDL cholesterol in the blood are the best ways to predict whether a person will develop atherosclerosis.
Other risk factors that can also have an effect are: women over age 55, heart attack or sudden death before age 55 in father or brother or before age 65 in mother or sister, cigarette smoking, high blood pressure, levels of HDL below 35 mg/dL, diabetes, lifestyle that is not active and/or obesity.
As the number of these risk factors increases, so does the risk of cardiovascular disease. Your doctor can make up a treatment plan to help you control some of these risk factors.
If you are very overweight or do not exercise enough, you add to your risk. Changes in your lifestyle can help you control some of these risk factors. The sooner you make changes, the better the chance you have to stay healthy.
Certain risk factors may be more key in women than in men. These include diabetes, high levels of triglycerides, and very low levels of HDL. If you have one of these risk factors as well as high cholesterol, your doctor may suggest you receive special care.
How High Cholesterol Affects Women
The leading causes of death in women are heart attack and stroke. In fact, cardiovascular disease causes twice as many deaths in women as cancer. The same number of women and men die from heart attacks, but women die at an older age.
The female hormone estrogen tends to protect a woman from the effects of too much cholesterol. But after menopause, the level of estrogen decreases. Then, a woman’s risk of cardiovascular disease begins to increase. By age 65, women have nearly the same amount of heart disease as men.
Some women who have reached menopause have used hormone therapy (HT) to protect against heart disease. Today, HT is no longer recommended for this protection. Talk with your doctor about HT and menopause. He or she can advise you about the benefits and risks for you.
Lowering Your Cholesterol
You can lower your cholesterol level by eating foods low in fat (especially low in saturated fat) and cholesterol and by losing weight. Exercise helps, too. It raises the level of good (HDL) cholesterol in your blood, helps you lose weight, and lowers your blood pressure. The good news is that there is a two–for–one benefit: your risk of heart disease goes down by 2% for each 1% that your cholesterol level goes down.
Change Your Diet
Read labels on all the foods you buy. The label will tell you how many grams of fat and how many calories are in each serving.
Fats should make up less than 30% of the total calories in your daily diet. Based on a 2,000 calorie a day diet, this is about 60 grams of fat each day. If you eat fewer than 2,000 calories a day, you should eat fewer than 65 grams of fat.
Each gram of fat has 9 calories. To find the total calories from fat, multiply the number of grams of fat in a serving shown on the label by 9. For instance, 1 ounce of potato chips has 10 grams of fat. This means that 90 of its calories come from fat (10 X 9 = 90). If the potato chips have a total of 150 calories, 60% of the calories come from fat (divide 90 by 150 = .60 or 60%). If more than 30% of the calories are from fat, that food is high in fat.
An ounce of pretzels has 110 calories and 1 gram of fat. This means that 9 calories (1 X 9) come from fat. Those calories are only 8% of the total (9 divided by 110).
Making changes in your diet can help lower your cholesterol level. You should eat more fiber (oats, beans, and fruit) and starches (grains and root vegetables like carrots, turnips, and potatoes). Eat foods that are low in cholesterol.
You also should eat foods low in saturated fat because this fat affects how cholesterol breaks down in the body. Saturated fat is solid at room temperature. It includes animal fats (butter and lard) and some vegetable fats (coconut, palm, and those listed on labels as “partially hydrogenated” oils).
Monounsaturated fats (olive, peanut, and canola oils) and polyunsaturated fats (safflower, sunflower, and corn oils) are better choices than saturated fats. Monounsaturated fats do not raise your cholesterol as much as saturated fats.
The best choice, though, is to limit all fats. Fat should make up less than 30% of the total calories in your diet. Based on a 2,000–calorie diet, this is about 65 grams of fat a day (see box). Women who eat fewer calories should eat fewer grams of fat.
Practice low–fat cooking methods such as: broil, steam, braise, bake, or poach foods, skim or cut all fat from food, cut back on butter, margarine, heavy sauces, mayonnaise, rich desserts and baked goods, and fried foods, when you eat meat, choose lean cuts, choose fish or poultry without skin and eat low–fat dairy products.
Aerobic exercise (such as walking, jogging, or swimming) raises your HDL (good cholesterol) level. It is best to exercise regularly, at least three times a week. Your doctor can help you choose a safe exercise plan.
Smoking lowers your HDL level and raises your risk of heart attack, heart disease, and stroke. It also increases your risk of lung cancer. If you smoke and are older than age 35, you should not use birth control pills. The combination greatly increases the risk of heart attacks, particularly in women older than 35 years.
If, after a few months, eating a healthy diet, exercising, and quitting smoking don’t work, your doctor may prescribe medication to lower your cholesterol. While you are taking medication, you still should keep eating a low–fat and low–cholesterol diet.
Heart disease affects many women. You should be aware of the role that cholesterol plays in your health. Talk with your doctor about getting your cholesterol checked regularly. To keep your risk of cardiovascular disease as low as you can, exercise, stop smoking, and eat a low–fat and low–cholesterol diet.