Creatinine is a waste product of muscle metabolism. When muscles work, they break down proteins, including the amino acid creatine, to produce energy. Most creatine is consumed but about 2 percent enters the bloodstream as creatinine. The kidneys remove most creatinine.

The biggest threats to Americans' health cause no pain or discomfort, but they lead to deadly heart attacks, strokes and liver disease. Two simple blood tests that analyze cholesterol levels and liver health can uncover these silent threats that plague more than half of all Americans.

Creatine is predominantly marketed as a supplement to improve athletic performance and increase muscle mass.

The liver is a four-lobed, triangular-shaped organ weighing a little more than 3 pounds. It is the largest gland in the human body, according to Procto-med.com. The liver is part of the gastrointestinal system and is located in the upper abdomen to the right of the stomach.

The prostate gland is part of the male reproductive system. It surrounds a portion of the urethra and makes some components of semen. As a man ages, the prostate sometimes enlarges in a condition called benign prostatic hyperplasia, or BPH, a noncancerous condition.

Your kidneys filter your blood and release toxic substances from digested foods into your urine for elimination. Some foods, especially when eaten in excess, produce waste products that can damage your kidney filtration capabilities, and your health.

A kidney removal surgery is called a nephrectomy. The surgery is done either through a large incision in the front or side of the stomach area or via a laparoscopic method, which involves 3 to 4 smaller incisions of about 1-inch in size, notes MedlinePlus.

The American Council for Drug Education reports marijuana, also known as THC for its active ingredient of delta-9-tetrahydrocannabinol, as the most commonly used illegal drug.

While most people take iron safely, excessive amounts of iron can be toxic. Symptoms may range from fatigue to life-threatening shock. The signs and symptoms of acute iron toxicity are different than those of chronic toxicity.

Bone scans and magnetic resonance imaging, or MRI, are tools used to determine the presence of certain diseases in bones. Both imaging tests are commonly used in the diagnosis of infections and cancer in the bones.

Your liver is a vital organ; liver functions include filtering harmful substances, such as alcohol and caffeine, from your blood and storing vitamins and minerals. Liver and gallbladder cleanses are popular, yet controversial, methods of promoting liver health.

Phentermine hydrochloride is the generic name of a prescription weight-loss drug. The medicine, which suppresses your appetite, is designed to support a diet program that includes regular exercise and nutritious meals.