All Humans are One of Four Blood Types: A, B, AB and O

Your blood type was determined by your parents, just like your eye color. Humans have only four blood types to choose from; A, B, AB, and O. These types are named for the kinds of protein that exist on the red blood cell's surface.

If you've ever had a blood transfusion, you know that your blood type is an important piece of knowledge. Some blood types are not compatible with one another, so the donated blood must be of the right type to mix with the transfusion recipient's blood. If the wrong blood types are mixed, clotting will occur, a dangerous situation that can cause death.

Called the "universal donor" because it can be transfused to all blood types, type O- blood donors are always in demand. Only 6 percent of the American population has this type of blood. People with type AB+ blood are called "universal recipients" because they can receive any of the other blood types. Only 4 percent of the American population has this blood type. The most common blood type is O+, with 37 percent of the population having this type.

If you don't know your blood type, your doctor can perform a simple laboratory test on a blood sample to determine it.

Cardiovascular Test: Stress Test

If you've ever had any heart problems, it's likely that your physician ordered a stress test for you. A cardiac stress test is often the first cardiovascular test used for diagnosing heart problems like arrhythmia and coronary artery disease. It's also useful to evaluate the success of a balloon angioplasty or bypass surgery.

Despite its name, the stress test is non-invasive and fairly basic. The point of the test is to challenge the heart, giving the physician the ability to notice conditions that may not be apparent when the heart is at rest. If your doctor is concerned about your risk for a heart attack, he may order a stress test to evaluate your heart's condition.

At the test itself, you will be hooked up to an electrocardiograph using several electrodes. The electrodes will communicate the electrical activity of your heart back to the electrocardiograph. Next, you will be asked to exercise on a machine, typically a treadmill, while the technician increases the speed and resistance. The technician will be monitoring your heart throughout the test and will also ask how you're feeling. If you feel any pain or are exhausted, ask that the procedure be stopped. The purpose of the stress test is simply to raise your heart rate to near maximum level, not to cause pain.

Health Risk Assessment: Evaluating Your Risk for Diabetes

Because we know a great deal about diabetes and its causes, it's relatively simple to determine if you are at risk for diabetes. When doing a health risk assessment for diabetes, several factors need to be taken into consideration.

Do you have a family history of diabetes?
If you do, your risk is higher.

Are you of African American, Latino, Native American, Asian American or Pacific Island descent?
If you are, your risk is higher because diabetes is more common in these ethnic groups.

Do you get moderate exercise most days of the week?
If not, your risk is higher.

Are you at a healthy weight?
If not, your risk is higher.

Do you eat a healthy diet, rich in fruits, vegetables and whole grains?
If not, your risk is higher.

Take a good look at the factors above and you can make your health risk assessment for diabetes. If you have questions or feel you are at risk, talk to you doctor about lessening your risk factors.

Prepare Adequately for Accurate Laboratory Tests

When you go to your doctor's office for laboratory blood tests, be sure you have prepared adequately for your test. To obtain a valid medical test result, you need to ensure that you've done your part to provide a good sample.

Before the day of the test, your doctor should provide you with instructions on how to prepare for your laboratory test. Whether you need to fast or avoid certain medications, deviating from the instructions can affect the test result. If you are not provided with instructions, ask if there are any. Be sure to follow them.

When you report for the test, inform your doctor if you did not follow the instructions. Tell your doctor or the person taking your sample what you did differently.

Alert your doctor to any medication you're taking or any foods you have eaten before the test.

Do not be embarrassed to tell your doctor the truth. He may go ahead with the test or he may reschedule, but at least you will know your results will be accurate.

Health Risk Assessment: Evaluating Your Risk For Alzheimer's disease

Alzheimer's disease is a particularly heartbreaking condition that generally affects people 65 and older. This degenerative brain disorder degrades a person's good judgment, learning capacity, memory and ability to reason. Alzheimer's may also cause anxiety or agitation as well as personality and behavioral changes.

While there is no single cause responsible for Alzheimer's disease, researchers are learning more about the condition every year. Because so little is known about the cause, a health risk assessment for Alzheimer's is relatively short.

Age – This is the most significant risk factor. For every five years after age 65, the Alzheimer's risk almost doubles. The risk is nearly 50 percent for those over 85.

Family history – Immediate family members (parents, siblings) with Alzheimer's disease greatly increase an individual's risk.