Your body needs vitamin C for its muscles, bones, cartilage and blood vessels; it also helps your body absorb iron. However, vitamin C does not necessarily improve cough symptoms. There are many potential causes of a cough, which include allergies, sinusitis or asthma, as well as a cold or the flu. Or a cough can be inherent of a more serious condition like emphysema, pneumonia, tuberculosis or even lung cancer. Vitamin C might improve a cough from some of these causes, but not from others. Talk to your doctor if your cough is persistent and does not go away or worsens.
Colds and the Flu
Colds and the flu are both accompanied by coughing as one of their symptoms. Vitamin C is commonly used for colds and the flu with the belief that it can cure or treat them. However, this idea is not confirmed by science. Vitamin C didn't reduce the onset of a cold or symptoms of a cold in over 30 clinical trials testing more than 10,000 people, according to MayoClinic.com. The only small benefit noticed was that about 10 percent of adults had colds that did not last as long as usual.
Although vitamin C does not necessarily help a cough from a cold or the flu, it might help your cough if you are a smoker. A February 2003 study in the journal "Respiratory Medicine" found that vitamin C in the diet of young Norwegian adults who smoked lowered their coughing and wheezing. Researchers surmised that the results were from the antioxidant value of vitamin C. However, this does not mean it is OK to smoke if you take vitamin C, as smoking has many negative health consequences.
Vitamin C might also improve a cough that stems from allergies. A dose of 2,000 mg a day might improve symptoms of allergies because of vitamin C's antihistamine qualities, explains the University of Maryland Medical Center. However, research is not conclusive on this potential benefit. This is a high dose of vitamin C, so talk to your doctor before taking it.
You can develop side effects from taking high doses of vitamin C to try to rid yourself of a cough. Too much vitamin C can lead to intestinal concerns, kidney stones, urinary problems and headaches. High doses are especially a concern for those with blood disorders, and they can interact with blood thinning medications, blood tests for diabetes and stool tests. Nonetheless, eating some foods with vitamin C might ease some of your symptoms, notes the University of Maryland Medical Center. These include kiwi, oranges and peppers.