“A lie repeated enough times becomes a truth”. Most of us have heard that what makes urine yellow when we take supplements is the B vitamins, specifically the B2 or riboflavin. Is this true?

Turns out NOT.  What makes urine yellow is a molecule called “urobilinogen”, a bile-related chemical that helps carry away certain toxins. Bile make urine yellow in a similar that it makes poop brown. People who do not make sufficient bile (certain liver and gallbladder diseases) have yellow poop, not brown, due to lack of bile-related molecules.

In conclusion, when we take our supplements and make bright yellow urine, it means that we have increased our urobiliogen output, which means we are carrying our more toxins. A GOOD thing!.

Furthermore, the opposite argument may also be true. If the urine is not yellow enough (other than drinking lots of water), then it can suggest a problem eliminating certain toxins. When we take a supplement and the urine turns yellow, it tells us that we have absorbed the proper nutrients to enable the increased production of urobilinogen. 

Finally, if you take supplements once a day and your urine doesn’t stay yellow, it suggests you need MORE vitamins in the 2nd half of the day (especially the water-soluble ones).