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Why do multivitamins turn urine yellow and should you be concerned about it?

If you’ve ever taken a multivitamin and noticed a change in the colour of your urine (i.e. something akin to fluorescent yellow!) you’re probably wondering if this is normal or something you should be concerned about! In this article we take a closer look at this common side effect of multivitamin supplements, why it happens and why it’s not something you need to be concerned about. Read on to find out more:

Multivitamin supplements typically contain a wide variety of essential vitamins and minerals. Higher quality supplements usually contain higher levels of these important nutrients. These vitamins and minerals are needed to support your health and ideally should be supplied by your diet. They can also be added in the form of a dietary multivitamin supplement during times of increased need or if you feel your diet may be falling short.

Among the essential nutrients typically supplied by a multivitamin are the B complex vitamins – a group of important B vitamins that have many important health roles to play including energy production, making red blood cells and supporting nervous system function. Since many of the B vitamins work together it is important that a multivitamin supplement supplies all of them as a group.

One of the B complex vitamins is called vitamin B2 or Riboflavin and when you take this in supplement form it will typically turn the urine bright yellow. This is called ‘flavinuria’. This is a harmless side effect and doesn’t necessarily mean that the dose being used is not needed or that tissue stores are saturated. There are no known toxic or adverse effects of high riboflavin intake in humans.

Hopefully now you can rest assured that whilst ‘luminous wee’ may look a bit strange, it is actually a normal and harmless side effect of taking multivitamins that you don’t need to worry about!

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