As you can imagine, the question ‘how many calories do you burn coughing’ is not one that has received a lot of funding or attention in the scientific community. As such, there has been no study to answer the query how many calories do you burn while coughing in any meaningful way, and the only thing we can do is to speculate.
A regular cough, such as one caused by mild irritation, is not likely to burn any measurable amount of calories above the basic burn rate. However, if you are coughing as the result of the flu, then your metabolism will be working faster than normal in trying to get rid of the infection. This means that you will be burning more calories than normal just trying to maintain your body’s core temperature. This increase in the number of calories burned can therefore not be said to be a direct result of the act of coughing, but rather a correlated effect.
There are other related factors to consider with respect to energy consumption if you are coughing as the result of an infection. For instance, you may be ingesting cough syrup on a regular basis, a substance that contains a surprisingly large amount of energy. Depending on the brand in question, cough syrup usually contains about 13-17 kcal per teaspoon. This is a very large amount for the small quantity in question – many times higher than the unhealthiest soft drink.