Why is urine yellow?

Urine gets its yellow color from a pigment called urochrome. That color normally varies from pale yellow to deep amber, depending on the concentration of the urine.

It actually doesn't change much over time. It stays the same color from the very beginning.

If it is a light color you are drinking enough water, if it is very dark the opposite is true.

Urine can turn many colors. Certain medications can turn the urine fluorescent green or blue, carrots can tint it orange, vitamins can give it a yellow hue, and an inherited disease called porphyria can shade it the color of port wine.

One drop of blood can turn all the urine in bladder red.

If you're seeing blood and your urine is also cloudy, there's a good chance you've picked up an infection.

Some foods can also change urine odor. Asparagus is among the most infamous.

What people are smelling when they eat asparagus is the breakdown of a sulfur compound called methyl mercaptan (the same compound found in garlic and skunk secretions).

Oddly, some people do not have the gene that allows them to smell mercaptan.