Matt Craver’s essay on why pee is yellow doesn’t address the vitamin effect - when you take certain vitamins, your pee becomes almost fluorescent. What causes that? I assume it’s not that vitamins cause massive instant red blood cell breakdown…
Link added by CKDH: http://www.straightdope.com/mailbag/murine.html
I asked this a while ago and if I recall, the answer is an excess of Vitamin C.
According to the leaflet attached to my Berocca (Multi-B vitamins), the fluorescence is caused by the excretion of excess B2.
Dottygumdrop, that sparks a memory. I think my original post was misremembered.
But now I’m thinking it is an excess of b12.
I’m going to search later and see if I can find the post I made a few years back.
Here’s my old thread on this.
“For awhile I went through a phase where I didn’t eat any food, I just ate vitamins. You know how many vitamins you have to eat until you feel full? Still, the color of my urine was amazing. I’d pee under an ultraviolet light and it was like a laser show.” - Steven Wright
I didn’t address the effect of vitamins and drugs because that wasn’t the question asked, and adding those ancillary issues would have made the article too confusing. Vitamin A can be metabolized into the orange pigment carotene, and B vitamins are water-soluble and can therefore be exreted unchanged. Some of these, especially riboflavin, are also orange or yellowish pigments.
Some “health” sites will tell you that bright neon yellow pee means you’re getting “enough” B vitamins, and that pale urine means you need to add a B complex to your vitamin regimen. This is almost exactly the opposite of the truth. B vitamins excreted in the urine are excess to the amount you need.
Medications such as Urostat can also affect urine color. Metabolic conditions, especially ones that affect protein metabolism or hydration, can also make urine darker or lighter.
“Matt Craver” is, of course, the pen name of our own paperback writer, and congrats on his first Staff Report!!
Notice how I carefully refrain from any mention of yellow journalism.
Maybe this column could be reprinted in the Pee Dee (the Plain Dealer, Cleveland’s major newspaper).
Could we get a link to the column, please?
And I knew him back when… ahhh … Fame…
The article says what happens to heme, but happens to the globin?
Brian
The globin portion is just protein. It gets broken down into its component amino acids, which are then available for general protein synthesis. This has no effect on urine color.
I have noticed that vitamin C, when taken in high doses, tends to cause my urine to appear more bright yellow or, as some have noted, to fluoresce.
I will point out that it is usually vitamins in pill form that do this, and so I suspect it might have something to do with the fillers in the vitamins. As a kid, I was always told to take high doses of vitamin C in situations when I would be near other kids I wasn’t used to (to build up my resistance to colds and stuff). The idea here is that there’s no such thing as “too much” vitamin C (you just pee the excess out) so just take as much as I wanted to. The chewables were pretty tasty, so I had a lot. I mean, a lot.
And my pee looked like a special effect in a movie. Steven Wright (one of the funniest comedians ever) was right.
But I also had an orange tree in my back yard, and eating a truckload of oranges wouldn’t have the same effect. On days when the oranges were particularly tasty, I could eat a huge quantity at once - enough to make my face and arms flush from too much acid. I’d have to take a break and drink some water until the flushing went away before I could continue eating them. But no yellow pee.
I’d also like to add that on days when I have a lot of water (I drink several liters per day), my urine will be clear most of the day, and only visibly yellow a couple of times. Those couple of times are soon after I take my daily vitamins - within a few hours. The yellowing effect takes longer than the stinking effect of asparagus, which I’ve noted can happen within 30 minutes of ingestion.
Vitamin C pills tend to be artificially coloured orange, so it’s likely that colouring having the effect, not fillers per se.
Well what I’d meant by “fillers” was “things not Vitamin C.”
Ooops, sorry. I’ve added a link to the bottom of the OP.
I got a shock the first time my wife made beet casserole. It made my pee bright red. I might say it scared the piss out of me, but obviously that was no great feat–given the circumstances.
Flavonoids to the rescue!
You guys should have seen the color of my unine years ago when I caught a dose of clap! The pills (and shots) the Doc gave me turned my pee bright orange!!
And I mean bright. Try explaing THAT to your pee neighbor in the urnial next to you. 
(Uh… I drink a lot of orange juice…)