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What Are Cholesterol Problems?

Cholesterol is a paradox: Everyone needs it, but too much of this good thing can spell trouble for some people. A soft fat-like substance, cholesterol aids vital bodily functions such as building new cells, and producing hormones.

The body gets cholesterol in two ways: 80% of it is produced by the liver and the rest comes from your diet. Cholesterol is found in foods derived from animal products, like meat, cheese, poultry or fish.

Note that foods that don't contain animal products may contain another harmful substance called trans-fats which cause your body to produce more cholesterol. Also, foods with saturated fats cause the body to make more cholesterol.

Cholesterol is carried through the bloodstream by attaching to certain proteins. The combination is called a lipoprotein. There are four different types of lipoproteins that carry cholesterol in the blood:

• High density lipoprotein (HDL) or "good cholesterol"
• Low density lipoprotein (LDL) or "bad cholesterol"
• Very low density lipoproteins (VLDL), which are very bad forms of cholesterol.
• Chylomicrons, which carry very little cholesterol, but a lot of another fat called triglycerides.

The amount of cholesterol in your bloodstream is important because of its role in various cardiovascular diseases. The risk of developing these conditions is complex and depends not only on how much cholesterol but also what kind of cholesterol you have in your blood. Generally speaking, high levels of LDL — the "bad cholesterol" — are associated with increased risk of developing coronary heart disease; high levels of HDL — or "good cholesterol" — are associated with decreased risk.

LDL cholesterol collects in the walls of arteries, initiating "hardening of the arteries" or atherosclerosis. People with atherosclerosis are in turn vulnerable to heart disease, heart attack, stroke and other problems caused by clogged blood vessels. Even so, some people who have high LDL cholesterol never actually get heart disease, and many heart attack victims do not have abnormally high cholesterol levels.

Cholesterol levels can increase with:

• Diets high in saturated fats or trans fats
• Obesity
• Sedentary lifestyle

Since no one can predict with certainty which people with high cholesterol will develop heart disease, play it safe and keep your cholesterol levels in check. The American Heart Association recommends that you eat less than 300 mg of cholesterol per day. Dietary control alone does not work for everyone; some people will also need to take medicines to reduce their cholesterol levels.

Another factor to consider is triglycerides — the form in which your body transports fat. In fact, the bulk of your body's fat is triglycerides. It's not clear whether high triglycerides alone increase your risk of heart disease, but many people with high triglycerides also have high LDL or low HDL levels, which do increase the risk of heart disease.

Low cholesterol levels (below 160) are not harmful to the body, but it may indicate the presence of another medical condition that needs treatment (like hyperthyroidism, malnutrition, pernicious anemia, or sepsis).

Who Develops Cholesterol Problems?

Most cholesterol problems are determined largely by luck of the genetic draw. Some families are genetically blessed with low total cholesterol or high levels of HDL ("good cholesterol"), regardless of diet or lifestyle. Other families inherit genes that increase their risk for high cholesterol. In these people, eating a diet high in saturated fat can significantly raise cholesterol levels. Stress can also raise blood cholesterol levels, especially since stress can lead to poor eating habits that may increase cholesterol intake.

On the positive side, vigorous exercisers — such as long-distance runners — tend to have high HDL cholesterol levels. Before menopause, women tend to have higher HDL cholesterol than men their age.

 

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