Glossary
UV inhibitor
An additive that helps slow the yellowing or fading of candle wax and color caused by light exposure over time.
A UV inhibitor is an additive blended into wax to help slow the yellowing or discoloration that can happen when a candle is exposed to light over time, particularly sunlight. It is most often used in white or very light colored candles, where any shift in tone is easy to notice.
UV inhibitors matter for candles that will sit on a shelf or in a window for weeks or months before being sold or used, since natural waxes and some fragrance oils can gradually shift toward a yellow or cream tone under light exposure. This is a slow cosmetic change rather than a sign the candle has gone bad, but it affects how a product looks in retail packaging or on a windowsill display.
Even with a UV inhibitor added, storing finished candles out of direct sunlight and away from bright display lighting for long periods helps keep colors truer for longer. A common mistake is treating a UV inhibitor as a guarantee against yellowing altogether, when it slows the process rather than stopping it completely.