Q & A: Urrrrrr ooooout!

Q: Why is pee yellow?

A: Pee is yellow mainly because of a pigment called urochrome (also known as urobilin).

Here’s how it works:

1. Red blood cells break down — When your body recycles old red blood cells, the haemoglobin (the part that carries oxygen) breaks down into several components.

2. Bilirubin forms — One of those components is bilirubin, a yellowish substance processed by the liver.

3. Urobilin is made — Bilirubin travels through your digestive system, and part of it is converted by gut bacteria into urobilinogen. Some of that gets absorbed back into the bloodstream and turned into urobilin, which your kidneys filter out into your urine.

4. Urochrome = yellow colour — Urobilin (urochrome) gives urine its characteristic yellow colour.

The shade of yellow can tell you a bit about your hydration:

• Pale yellow or nearly clear → you’re well-hydrated.

• Medium yellow → normal, healthy range.

• Dark yellow or amber → you may be a bit dehydrated.

Certain foods, vitamins (especially B vitamins), or medications can also temporarily change the colour — but the baseline yellow always comes from urochrome.

Source: Some or all of the content was generated using an AI language model