As Lloyds Pharmacist Nitin Makadia told the publication, "hydrochloric acid has a very important function to support the digestion of food and is therefore released when you eat, smell or even start thinking about food. Coffee, even decaffeinated coffee, has been shown to stimulate production of acid which, in the absence of food, can be damaging to the lining of the stomach with repeated exposure."
Dr Adam Simon, chief medical officer at PushDoctor.co.uk, agreed, saying that drinking coffee before food "can increase the amount of water you pass and can potentially create symptoms of dehydration. It can affect your pulse, causing an irregular heartbeat by putting pressure on the heart, and it can adversely affect your blood pressure." Not only that, it can cause heartburn and indigestion, thanks to the acidity.
On top of that, there is research that shows caffeine consumption can trigger feelings of anxiety, especially in people with diagnosed anxiety disorders. This seems logical, considering I myself have experienced the jitters and shakiness that result from drinking too much coffee on an empty stomach. This is why, from here on out, I'm not going to spring out of bed and head straight for coffee. I'm going to start by filling up my BKR water bottle ($35), because hydration comes first, and only indulge in my favorite caffeinated beverage after a full breakfast.