Dark yellow urine is often thought as an indicator of some alarming medical conditions. However, many times, changes in urine coloration can be brought about by some minor factors like dehydration or intake of certain medicine and foods. This article describes the causes of dark urine and the symptoms associated with the condition.

Urine is a colorless to pale yellow colored transparent liquid excretory product. It basically contains water and water-soluble waste products, which are generated during the metabolic processes, taking place within our body. Urine mainly contains nitrogenous waste materials like urea, uric acid, and creatinine, and a small amount of mineral salts and enzymes. Kidneys filter the blood to extract these liquid waste materials, which are then expelled from the body along with some water through the process, known as micturition or urination. The urine formed in the kidneys is carried by the ureters to the urinary bladder, which retains it, until it is expelled through the urethra. The presence of the pigment 'urochrome' imparts that characteristic pale yellow color to urine.

Dark Urine Causes
As has been mentioned already, the urine of a healthy individual is colorless, or pale yellow in color. Any change in urine color can be a symptom of several health conditions. So, dark color can be caused by several factors, ranging from the consumption of certain foods, inadequate fluid intake to ingestion of some medications and certain serious diseases.

-- Dehydration or insufficient fluid intake is the most common cause of dark yellow urine. Dehydration can cause the urine to become concentrated with waste materials, and can transform it into a dark yellow colored liquid. Dehydration is the most important reason for passing unusually dark urine in the morning.

-- Another common factor that can cause this condition is consumption of certain foods. As for example, urine can assume a dark yellow color, due to consumption of asparagus, while consuming a large amount of beet can impart reddish purple color to it. Again, consuming a lot of blackberries and rhubarb can also impart a red tinge to it.

-- Many times, it can result from intake of certain drugs, or supplements. Vitamin supplements, especially supplementation of vitamin B can make the urine dark yellow colored. On the other hand, vitamin C can give it an orange or bright yellow color. Like supplements, certain drugs like quinine derivatives and nitrofurantoin can also cause the urine to become dark yellow or brown colored.

-- Cystitis or Urinary Tract Infection is one of the most common factors, causing dark urine during pregnancy; the other factor being dehydration due to morning sickness. Persistent abnormal coloration of urine can be associated with diseases like cystitis or urinary tract infection.

-- Diseases of the liver such as jaundice, Cirrhosis, and hepatitis can also cause dark yellow to brown colored urine.

-- Hemolytic Anemia is a condition associated with the excretion of dark yellow to brown colored urine. This condition is characterized by abnormal breakdown of red blood cells, and their excretion along with urine.

-- Red blood cells can also be present in urine, giving it a dark yellow to red tinge, due to hematuria, which can be caused by several factors including kidney stones, urinary tract infection, and gallstones.