Health and Fitness (Q&A)

Answer:

The yellow colour in urine is due to chemicals called urobilins. These are the breakdown products of the bile pigment bilirubin. Bilirubin is itself a breakdown product of the heme part of haemoglobin from worn-out red blood cells.  Urine can range from clear to a deep amber colour in a healthy person. The level of yellow in the urine is determined by how hydrated a person is. A person who is very hydrated has more water to release through urinating, and thus has a lesser concentrate of urobilin in their urine. A person who is very dehydrated will have a much higher concentration, and thus much darker urine. Some foods, such as beets, may temporarily change the colour of urine. Eating a lot of carrots, or drinking a lot of carrot juice, can turn urine orange. Asparagus can make urine much brighter in colour, as can some vitamins - usually vitamins C and B. Certain medications can also affect urine colour, as can food dyes. An unusual urine colour may also indicate a health problem. Brown or red urine could indicate a severe problem in the kidneys, for example.

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