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Question: What changes the color of your urine and why?

Asked by: Kerstin McKoy
School: Vestal Hills Elementary
Grade: 5
Teacher: Mr. Greenman
Hobbies/Interests: Art and Soccer
Career Interest: Veterinarian

Answer from Jennifer Wegmann

Lecturer, Binghamton University

Research area Eating disorders and body image
Interests/hobbies: Exercising, reading, writing
Family: Husband, Tom; two Sons - Nick (13) & TJ (11)  

Think of urine as a means by which the body removes excess water, waste, and toxins. When the kidneys filter blood the waste is then eliminated through urine. There are many factors that can affect the color, most of which are harmless and temporary. The yellow coloring comes from a pigment called urochrome and in healthy well-hydrated people urine will be a pale yellow color. The shade of yellow can be dictated by a person’s hydration status.  The more water a person drinks the more diluted the urine and the lighter the color. In contrast, when a person is dehydrated their urine is more concentrated and a darker yellow.  Taking a multi-vitamin will also change the color of a person’s urine. B Vitamins are water-soluble and when we take in too much our kidneys filter them out and they can make urine look neon yellow to a greenish color. There is no need to be alarmed; it is not life threatening it is just your body’s way of preventing toxicity from taking in to many B vitamins at one time.

Beta –carotene, found in carrots, can also add a tint of orange to urine. People who consume high quantities of carrots, especially through juicing, many notice this change. Other foods like beets can also change the color or urine. There are also many medications that can affect color like laxatives and the prescription blood thinner Coumadin.

Although it can be normal to experience differences in urine color, some changes, like cloudiness or opaqueness, can be an indication of something more serious like an infection or a disease. In some cases, blood can leak into your urine. This will give it a red or brown color and is a signal that something is wrong.  Changes in odor can also be normal; for instance if you eat asparagus or tuna fish. If changes in color and odor last longer than a few days one should contact their doctor.


Last Updated: 3/1/17