Glutathione IV Therapy: Benefits, Side Effects, and More Vitamin B supplements, especially those containing riboflavin (vitamin B2), often cause bright yellow or neon colored urine. This happens because excess riboflavin is water soluble and is excreted through urine when the body has Why is my urine bright yellow? Get the Gloss The standard color of your urine is referred to by doctors as urochrome. Urine naturally carries a yellow pigment. When you're staying hydrated, your urine will be a light yellow, close to clear color. Glutathione: The Master Antioxidant Core Med Science