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BCAAs Affecting Urine Colour

I recently started taking BCAAs during my workouts, and have noticed that my urine turns bright yellow after that. Is this a cause for concern? I’m only taking a very small amount (<5g) as I wanted to see how my body would respond to it before increasing the dosage.

Are you sure you aren’t also taking extra Vitamin B2?

Are you also taking a multivitamin or a vitamin b2/riboflavin supplement?

EDIT: Bill got to it first. Facepalm.

Oh yea I just checked the label and apparently I’ve also been consuming just over 10mg of Vitamin B2 per workout. No wonder I didn’t come up with anything when I googled BCAAs with urine colour. Anyway, Vit B2 is supposedly not toxic when consumed in excess right? Hmm I wonder why they put so much of it in each tablet if we can’t absorb that amount of it anyway.

If you didn’t absorb it, why would it be changing the color of your urine?

You are absorbing it, thats why its changing the color of your urine. However, obviously you’re excreting it. Toxicity is very rare with vitamin B2. No worries.

EVERYTHING (read:water, air) is toxic when consumed in excess.
But I’m more than sure that you’re nowhere near dangerous amounts. So I wouldn’t worry about it
And as has been already said- you ARE absorbing it.

Urea is a byproduct of protein breakdown and is excreted through urine. More protein consumption = more urea. I don’t think there’s any cause for concern.

How has the BCAA during workout been working for you? How much do you take?