Yup - because white is a mix of all colors, while a LED typically emits light heavily centered around a specific color/wavelength...

As a result of one of those pub conversations that started with "Show me something macroscopic that demonstrates that quantum mechanics is real", it turns out that you can predict the colour of an LED from its voltage drop, or vice versa, with complete accuracy by converting eV to joules for the incoming electrons and using E=hf for outgoing photons, on the quantum-mechanical basis that each electron's energy is released in exactly one photon.

Peter