Cholesterol is a fatty substance made by your liver. And despite its bad reputation, you actually do need it. It helps to form cell membranes and some of your hormones.
Your body makes all the cholesterol it needs. But when you eat foods high in saturated fat, it triggers your liver to churn out more cholesterol, much more than you require. That excess cholesterol builds up in your arteries, blocks blood-flow and, if left untreated, can set the stage for a heart attack or stroke. When we say you have high cholesterol, it means that the total amount of cholesterol in your bloodstream is above a certain number that experts have deemed a risk to your health.
But there's more than just your total cholesterol. There are actually two types of cholesterol — low-density lipo-proteins (referred to as LDL) and high-density lipo-proteins (called HDL). Lipo-proteins are combinations of fat and protein made by your body. They are responsible for delivering other fats, which don't dissolve in your blood, to your cells.
What doctors have realized in recent years is that your LDL and HDL levels may be just as, if not more important as, your total cholesterol reading. Each type has a different action, and therefore a different impact on your heart health.
LDL, often called the "bad" cholesterol, carries most of the cholesterol in the blood. When there's too much LDL, it can combine with other substances to form a plaque — a hard, thick deposit that sticks to artery walls. If a blood clot develops in the vicinity of a plaque, the reduced blood-flow can lead to a heart attack or a stroke. Experts now think that the lower your LDL level, the better.
HDL is known as the "good" cholesterol. It carries about one-fourth to one-third of the cholesterol in the blood, transporting it from different organs to the liver for disposal from the body. HDL may also pick up cholesterol deposited in your arteries and move it out, preventing it from building up in your arteries.
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A heart attack is an event that results in permanent heart damage, and can result in death.
It is also known as a myocardial infarction, because part of the heart muscle (myocardium) may literally die (infarction) from lack of oxygen.
A heart attack is caused by a blockage in one of the coronary arteries.
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A cardiac arrest is a life-threatening situation in which the heart abruptly stops. The person must be treated with a defibrillator within minutes in order to survive.
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Atherosclerosis is the final step in the hardening of the arteries.
LDL ("bad") cholesterol produces poisons (toxins) that damage the lining (endothelial cells) of the inside wall of an artery.
This damage contributes to the formation of tiny wounds or lesions on that inside wall. Other fatty materials in the bloodstream (e.g. triglycerides) are attracted to those lesions and begin to build up there.
White blood cells rush to the site of the irritation to devour harmful substances, but only cause the lining of the artery to become sticky, attracting even more LDL molecules.
Clot-producing platelets begin to collect over the site, releasing still more irritating substances and trapping more fatty particles and white blood cells.
This gradual build-up of fatty materials and toxins is known as plaque. As the plaque continues to build up, some of the plaque formations develop a relatively thick covering (due to calcification). This process of calcification led to the common term for atherosclerosis: “hardening of the arteries.”
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Hypoglycemia, or low blood glucose, also called "insulin reactions," occurs when your blood glucose level is 70 mg/dL or less. Hypoglycemia develops when there is too much insulin and not enough glucose in your body. It requires immediate treatment.
Hypoglycemia can only occur if you take insulin or certain types of oral diabetes medicines to manage diabetes.
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Insulin is a hormone that controls blood glucose. It is injected instead of taken in pill form because when insulin is taken by mouth the acids in your stomach destroy most of it. Injecting insulin under the skin bypasses your stomach and allows it to stay in your body for different lengths of time, depending on the type of insulin used.
There are many forms of insulin. They are classified by how fast they start to work and how long their effects last.
People with type 2 diabetes tend to have two problems that lead to increased glucose in the blood stream:
- They don't make enough insulin to move glucose into cells.
- The body's cells become "resistant" to insulin (insulin resistance), meaning they don't take in glucose as well as they should.
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Diabetes is a disease that prevents your body from properly using the energy from the food you eat. Diabetes occurs:
- When the pancreas (an organ behind your stomach) produces little insulin or no insulin at all, or
- When the pancreas makes insulin, but the insulin made does not work as it should. This condition is called insulin resistance.
Insulin is a naturally occurring hormone that helps the body use glucose for energy. The body is made up of millions of cells. To make energy, the cells need food in a very simple form.
When you eat or drink, much of your food is broken down into a simple sugar called glucose. Glucose (sugar) provides the energy your body needs for daily activities.
Your bloodstream transports glucose from where it is either taken in (the stomach) or manufactured (in the liver) to the cells where it is used (muscles) or where it is stored (fat).
The glucose in your bloodstream cannot go into the cells by itself. The pancreas releases a substance called insulin into the blood which serves as the helper, or the "key" that lets glucose into the cells for use as energy. When glucose enters your cells, the level of glucose in your bloodstream decreases.
Without insulin, glucose cannot get into the body's cells for use as energy. This increases the levels of glucose in your blood. Too much glucose in the blood is called "high blood sugar" or diabetes.
There are three types of diabetes:
- Type 1 diabetes occurs because the insulin-producing cells (called beta cells) of the pancreas are damaged. People with type 1 diabetes produce little or no insulin, so glucose cannot get into the body's cells for use as energy. This causes blood glucose to rise. People with type 1 diabetes must use insulin injections to control their blood glucose.
The damage to insulin-producing cells in type 1 diabetes occurs over a period of years. However, the symptoms of type 1 diabetes may occur over a period of days to weeks. Type 1 is the most common form of diabetes in people less than 20 years old, but it can occur at any age.
- People with type 2 diabetes produce insulin. However, the insulin produced is either not enough or doesn't work properly in the body. When there is not enough insulin or the insulin is not used as it should be, again glucose can not get into the body's cells for use as energy. This causes blood glucose to rise.
Type 2 diabetes is most common in people over age 40 who are overweight. Some people with type 2 diabetes can manage it by:
- controlling their weight,
- watching their diet and
- exercising regularly.
Others may also need to take an oral glucose-lowering medication or insulin injections.
- Gestational diabetes is a high blood glucose level that is discovered during pregnancy. As pregnancy progresses, the developing baby has an increased need for glucose. Hormone changes during pregnancy also affect the action of insulin, resulting in high blood glucose levels.
Pregnant women who have an increased risk of developing gestational diabetes are those who are:
- over 25 years old,
- are above their normal body weight,
- have a family history of diabetes and
- are Hispanic, African-American, Native American or Asian.
Usually, blood glucose levels return to normal after childbirth. However, women who have had gestational diabetes have an increased risk of developing type 2 diabetes later in life.
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