You hear about the risks of high cholesterol all the time. You also hear that there is something called good cholesterol. What is the difference? Time to get right down to the facts in an every-day, conversational approach.
CHOLESTEROL 101
Cholesterol is a fat-like substance -- a steroid. It exists in the human bloodstream, in the cells of the human body, and in foods. It is a waxy substance, almost like a melted candle in consistency.
Cholesterol is not a dirty word. We hear, "you need to watch your cholesterol" all the time, but cholesterol is necessary to your body's ability to run like a well-oiled machine.
Cholesterol is used to form and maintain the cells of the body. Some cells can be changed by temperature; cholesterol comes to the rescue to help cells maintain their efficiency and form.
Cholesterol is an important part of the formation of sexual hormones like as estradiol and testosterone. These, and other hormones, are not only important to sexual function and reproduction, they are also key to bone structure and organ efficiency.
Ever wonder how sunlight becomes vitamin D? Cholesterol is the answer. It acts as a major component in the conversion of vitamin D when the skin is exposed to the rays of the sun.
Your body forms most of the cholesterol that flows through your blood stream. This kind of cholesterol is called endogenous cholesterol, the kind that does not come external dietary sources. Only about 15% of the cholesterol in your system comes from your diet. It is possible to replace a larger percentage of your endogenous cholesterol by increasing your intake of dietary cholesterol; this can be dangerous. High levels of dietary cholesterol can build up plaque in the blood vessels that can limit the flow of blood, much like pouring oil down a sink drain. If the coronary arteries are blocked, a heart attack may occur. Block-up of blood vessels in the brain can cause a stroke.
CHOLESTEROL: THE GOOD AND THE BAD
Cholesterol cannot dissolve in water; hence, it cannot dissolve in blood. Therefore, the body uses carrier molecules called apoproteins to transport the necessary cholesterol through the body. Apoproteins and cholesterol bond to form a compound called lipoproteins. Lipoproteins are not all the same; some have a higher amount of proteins than others. Protein rich lipoproteins are called high-density lipoproteins (HDL) these are the good guys. Protein deficient lipoproteins are called low-density lipoproteins (LDL); these are the bad guys.
LDL tends to leave cholesterol deposits that, along with other substances, build up plaque on the inner walls of the blood vessels. This can hamper the necessary blood flow that feeds the heart and the brain. If an artery is clogged due to a clot in a narrowed artery, the results can be lethal -- a heart attack.
HDL, on the other hand, acts like a cleaning agent; it not only abstains from depositing cholesterol in the arteries, but cleans the inner walls of the blood vessels. HDL carries excess cholesterol through the system to the liver where it is passed by the body. About a quarter to a third of your blood cholesterol is carried by HDL. Low levels of HDL in the blood can be a red flag for heart attack risk.
WATCHING YOUR CHOLESTEROL
Now that you understand what cholesterol is, how can you fight against plaque buildup in the arteries? The answer is to watch what you eat. Fat is a necessary part of your diet. Some vitamins can only dissolve in fat. Even if they don't contain cholesterol, saturated fats can increase cholesterol levels in the blood.
Some foods are simply high in cholesterol. Some examples are eggs, red meat, and shellfish. These foods can grossly increase cholesterol levels, especially when combined with foods that are high in saturated fat.
Check nutrition labels for fats and saturated fats. You should try to keep fat at or below 30% of your total daily calorie intake. The American Heart and Lung Association recommend that you should intake no more than 300 milligrams of cholesterol per day. Watch the saturated fats, found in foods like shortening, chocolate, whole milk and butter. Keep them to a minimum. In short, increase your consumption of nutrient-rich fruits and vegetables and decrease your consumption of fatty foods like meats, nuts, avocados, and eggs. It doesn't have to be complicated. Think of your meal plate as a pie chart. Limit the meat and fatty foods to a 15 to 30% slice and fill the rest up with fruits and vegetables.
