A new study shows that American's are getting "shorter" while other countries in the world continue growing to new vertical limits.

Pseudoephedrine is a decongestant medication sold over the counter (such as in Sudafed). It is also found as a component in some prescription medications. Pseudoephedrine is available as a tablet, chewable tablet, controlled-release tablet, capsule, syrup, suspension and liquid and as drops.

The primary function of the heart is to pump oxygenated blood throughout the human body as part of the circulatory system. When a person exercises, the heart rate, otherwise known as the pulse, will increase rapidly with the output of energy.

The human body uses energy from food to fuel movement and essential body functions, but the body cells don’t get energy directly from food.

Whole blood consists of 3 types of blood cells, suspended in a liquid called plasma. Blood circulates through the arteries and veins with each of the blood cell types -- red blood cells, white blood cells and platelets -- performing different functions throughout the body.

As soon as food enters your mouth, it starts the process of digestion. Food needs to be broken down into smaller nutrients so that the body can store or utilize it. Your body produces specialized enzymes that work on digesting the different types of foods you consume.

Blood clots that form to halt bleeding after an injury can be life-saving. But clots that form spontaneously within a blood vessel -- in the calf or elsewhere in the body -- could be a sign of trouble. The calves are the most common site of spontaneous blood clots.

Alkaline phosphatase -- commonly abbreviated as ALP -- is a protein found in all cells of the body. The highest concentrations of ALP are located in cells of the liver, bones and bile ducts. ALP in the blood is primarily derived from excess ALP that is released from these cells.

Cortisol is the primary hormone released by the body during times of stress. Although cortisol does have necessary functions in the body, such as regulating energy and dictating energy sources, elevated levels, particularity over extended periods of time, can have several negative side effects.

Potassium levels in the body must be carefully managed to avoid complications that arise with high or low levels. Potassium supplements may be appropriate if your body is deficient in this nutrient. Several different types of potassium supplements are available.

Symptoms of final stage colon cancer can vary, and they typically depend on the areas of the body affected by the cancer. Abdominal pain or other gastrointestinal symptoms are common. They may arise from the cancer itself, scarring from previous radiation or surgery, medications or palliative chemotherapy.

A pediatrician orders a creatinine test as part of a screening to check for decreased glomerular filtration rate. The GFR is directly linked to kidney function. Health care providers use this test to determine how well the kidneys are working. Pediatric reference ranges are based on the child's age.