Drinking too much of this might be making your cough worse

When you hear someone coughing next to you, it's normal to wonder what's causing the cough. Do they have a cold? Are they sick? Are they contagious? But do you ever wonder if their morning cup of coffee might actually be the culprit?

Singers have long been counseled to avoid coffee before performances because of the supposed damage it can do to vocal cords. But the evidence to support this claim is sketchy and most of it is anecdotal. One very limited 1999 study did suggest that caffeine could have a negative impact on vocal quality, but even those results were inconsistent, varying substantially between participants (via Cambridge University Press).

When it comes to coughing, it's true that large amounts of caffeine can cause dehydration, which can lead to a dry throat, which can in turn aggravate or worsen a cough (via Livestrong). Coffee is a mild diuretic, after all. But it takes more than your morning cup of joe to get to this point. 

Coffee can actually contribute to daily fluid needs

For coffee to have a significant dehydrating effect, you would have to drink more than five cups of brewed coffee per day, giving you more than 500 mg of caffeine (via Healthline). On the contrary, experts now believe that, in moderate amounts, coffee consumption should be counted towards a person's daily fluid intake.

Nathalie Rhone, RDN, a New York City-based nutritionist, told Eat This, Not That!, "In order to experience a dehydrating effect, a person would need to drink far more cups of coffee or tea in one sitting than even the most caffeine-addicted individuals consume in a day."

Also, a small number of people have a caffeine allergy, which can cause coughing after drinking even small amounts of coffee.

Overall though, while large amounts of coffee could aggravate a cough, moderate amounts are unlikely to make it worse.