The over 150-year mystery of why urine is yellow has been cracked: study

We've known that urine's color comes from the bile salts (biliverdin, bilirubin) for years and years.

In the tropics, particularly, urine color is used as a general-purpose indicator to how dehydrated you are. The more dehydrated, the darker the urine. In a cargo boat I once travelled in, there was a color-chart in every toilet to teach the crew about dehydration, and the necessity to drink more water if the urine was too dark.

The brown color of shit also comes from the same bile-salts. When people have a bile-duct blockage that lasts long enough their shit is described as 'putty-like' (that very pale gray-beige color)

The article sounds like it was written by a journo who's a bit light-on with scientific knowledge.