Have you ever looked at your tissue after blowing your nose and wondered why your mucus is a certain color? And what exactly does it mean? Dr. Stacey Rose, associate professor of infectious diseases at Baylor College of Medicine, shares what you need you know when it comes to your nasal secretions.
Q: There is an old wives’ tale that your mucus color can tell you if you’re sick. Is this true or a myth?
A: It is not quite accurate but perhaps partly true. For example, a runny nose due to allergies is typically associated with clear mucus, while bacterial sinus infections are classically described as having “purulent” discharge (meaning thick and yellow-green in color). But there are many in-between situations. For example, viral infections often start with clear nasal drainage but that doesn’t mean you’re not sick!
Q: What can the different colors mean if anything?
A: The body has a variety of defense mechanisms when confronted with an infection. Mucus is made up of tissue,cells (such as from the lining of the nose or throat and also immune cells such as white blood cells) and secretions to help move infection out of the body. Dead bacterial cells can also form part of the mucus. The components of mucus are what give it its color, and there can be a wide range of colors – from tan to yellow to green to gray or even blood-tinged. We often think of bacterial infections as causing more of a vigorous response of white blood cells, leading to a yellow-green color, but again this is not a hard and fast rule.
Q: Could certain lifestyle activities (like smoking) change the color?
A: Smoking can damage the lining of the nasal cavities and airways, and can affect the immune response to infection; smokers are at higher risk of respiratory infections in part due to these effects. Because mucus is made up of tissue and immune cells, I do believe lifestyle activities such as smoking could affect the color of mucus.
Q: Could the consistency of your mucus tell you if you’re sick?
A: As above – you can be sick and still have thin mucus, especially with a viral infection. I would say it can be helpful to note the consistency of mucus as it evolves; if you start with clear mucus, and then it becomes thick and yellow-green (“purulent”) then that could be a sign that the infection is progressing. But it can also indicate that your body is responding just as it should – by recruiting white blood cells and other immune cells to fight the infection.
Q: When should someone call their doctor?
A: As with many clinical signs and symptoms, it can be hard to pinpoint one feature that would prompt a doctor visit. Beyond the color of mucus, it is best to consider a constellation of signs or symptoms – for example, fever can often be a sign of infection, as well as headache, pressure in the sinuses, cough and shortness of breath. When to call your doctor also depends on your own health; if you have underlying health problems, you would want to call your doctor sooner than perhaps someone with a healthy immune system who might be able to monitor their symptoms for a few days before seeking medical attention. A general rule of thumb: If things are getting worse rather than better, it’s time to call for help.
By Anna Kiappes