That's right, the color and consistency of your nasal discharge or what you cough up can shed some light on your ... Like ...

If you’re coughing up light-colored or clear mucus ... If you’re coughing up yellow or green mucus, it may indicate that you have a respiratory infection. Your mucus changes color because ...

Typically, phlegm is somewhat clear with a cloudy or whitish tint to it. When phlegm has a yellow, green, or red color to it, ...