Bright Yellow Urine: Vitamin Supplements Explained

[lisab]

I take a multi-vitamin supplement about 5 days a week. What is it in the pill that makes my urine turn bright, bright yellow? It looks almost fluorescent sometimes!

 

[Moonbear]

I take a multi-vitamin supplement about 5 days a week. What is it in the pill that makes my urine turn bright, bright yellow? It looks almost fluorescent sometimes!

One of the B-vitamins...IIRC, it's the folate.

 

[chemisttree]

Does folate have a visible chromaphore? I always thought that color was due to the bright yellow riboflavin (B2).

 

[jim mcnamara]

pterins (folates as cryptochromes in leaves) have been shown to have max absorption at 380nm. It would give an orange-ish color I presume. Assuming folates in urine are similar.

http://mplant.oxfordjournals.org/cgi/content/full/1/1/68

However I always thought riboflavin was the major color culprit, too.

 

[Evo]

When I take a pill high in iron, the excess iron turns my urine dark yellow or orange.

 

[Moonbear]

Does folate have a visible chromaphore? I always thought that color was due to the bright yellow riboflavin (B2).

Could be...I was certain on the B vitamin part, but since I've never seen any of the B vitamins individually, just as a complex, I could very well be wrong on which one it is that's the yellow culprit.

Edit: Yep, digging around, it is B-2. Even found an ancient archived thread here on it (but am not providing a link to it because it also contained some old crackpottery we wouldn't allow under current guidelines). My apologies for the misinformation about it being folate.