Does caffeine cause heartburn?

You enjoy coffee. It is flavorful, has aromatherapeutic properties, and provides a necessary caffeine boost to kickstart your day. Coffee may increase dyspepsia symptoms like poor digestion and heartburn. The research indicate the correlation between coffee and heartburn is not at all clear-cut and could be associated with the complicated interaction of coffee type, coffee origin, the roasting process, the method of preparation, dietary preferences and individual sensitivity. 

Why Coffee Causes Heartburn 

Statistics show that approximately 25% of the population globally have non-ulcer stomach pain or discomfort, known as functional dyspepsia with unexplained indigestion symptoms.

Heartburn occurs when stomach acid rises up into the esophagus (the tube that connects your throat to your stomach). Normally, a little bit of acid reflux is nothing to worry about. But if it happens frequently or causes discomfort, it might be a sign of gastroesophageal reflux disease (GERD).

Coffee consumption is known to trigger salivary enzymes and stomach acid secretions. Caffeinated coffee, especially ground coffee but also instant caffeinated coffee, stimulates more effectively gastrin secretion than decaffeinated coffee, pointing to the role of caffeine in unexplained indigestion. It is believed, but remains controversial whether these factors, and mainly coffee, may causally relate to the heartburn. Other studies have indicated that smoking, taking aspirins, eating spicy foods, and some infections are major risk factors as well.

 Coffee can exacerbate heartburn for a few reasons:

 
 Coffee is acidic. That means it can contribute to increased stomach acidity, which in turn can lead to heartburn.
Coffee relaxes the lower esophageal sphincter (LES). The LES is a muscle at the bottom of the esophagus that acts like a valve between the esophagus and stomach. When it's functioning properly, it opens just enough to allow food and liquid into the stomach and then closes again. But when the LES is relaxed, it doesn't close as tightly, and stomach acid can rise up into the esophagus, causing heartburn. 
Coffee is a stimulant. Caffeine stimulates production of hydrochloric acid in the stomach, which can also contribute to increased stomach acidity and heartburn. 
 Some people are more sensitive to coffee's effects than others. If you have GERD or are otherwise sensitive to the effects of caffeine or acids, you're more likely to experience heartburn after drinking coffee.
Drinking large amounts of any fluid during meals can increase stomach volume and trigger heartburn. So even if coffee itself doesn't cause heartburn for you, drinking several cups with meals could still lead to symptoms. 

Solutions for Heartburn Sufferers

 
If you love coffee but frequently suffer from heartburn, there are a few solutions that might help lessen your symptoms:
 Use an alkaline water filter: Alkaline water has a higher pH than regular tap water, which means it's less acidic. That could make coffee less likely to trigger your heartburn symptoms.

Try cold brew: Cold brewing involves steeping coffee grounds in cold water for 12–24 hours before filtering out the grounds and enjoying your coffee concentrate diluted with water or milk over ice—or heated up, if you prefer. Because cold brewing takes longer and uses cooler temperatures than hot brewing methods like drip coffee makers or French presses, it may produce coffee with less acetic acid (one type of acids found in coffee), which could make it more tolerable for people with GERD or other sensitivity to acids in coffee..

Drink decaf: Decaf coffees undergo a process that removes most of the caffeine while leaving behind many of the chemicals responsible for flavor (including acetic acid). So if you're looking for a low-acid solution that still tastes like real coffee rather than herbal tea posing as fake coffee, decaf could be your answer..

 Add milk: A splash of milk or cream in your cup of joe can help neutralize some of the acids present in freshly brewed coffee..

 Wait before working out: Eating or drinking anything—coffee included—causes an increase in blood flow to your digestive system muscles so they can break down food..

 Don't drink on an empty stomach: When you drink on an empty stomach, gastric acid is more likely to rise up into your esophagus because there's nothing else there to buffer it..

 Drink through a straw: This one might sound weird, but bear with us: Sucking fluid through a straw places less strain on the LES than gulping does..

 Take an antacid: Persons with heartburns are advised to avoid aspirin and non-steroidal anti-inflammatory drugs (NSAIDs), smoking, and drinking and alcohol. If all else fails and you're really craving a cup of hot java but don't want the resulting indigestion misery, take an over-the-counter antacid like Tums or Rolaids before indulging..

For most people, occasional heartburn isn't anything to worry about. But if you have GERD , consult with your doctor about ways to manage your symptoms and enjoy your favorite foods and drinks without pain.. cheers!

Positive Effects of Coffee consumption

The data reviewed here show that coffee intake stimulates gastric, biliary, and pancreatic secretions, seeming to favor the first steps of the digestive process. 

Coffee stimulates the motor activity of the colon, and its use is now recurrently suggested as a non-harmful adjuvant to restore colonic contraction and function.

Coffee consumption induces changes in the composition of the gut microbiota, mainly at the level of the population of Bifidobacteria, Bacteroides, and Prevotella. 

Coffee consumption has not been reported to generate any deleterious effects on the various organs of the digestive tract.

Coffee Consumption offers protective effects against hepatic carcinoma and all other liver diseases.

Several studies from Europe, America, and Australia have not found any relation between coffee consumption and dyspepsia while others from the USA, Iran, and China found an association between coffee consumption and functional dyspepsia. Nevertheless, additional data are greatly needed

Reference: 

Effects of Coffee on the Gastro-Intestinal Tract: A Narrative Review and Literature Update -by Astrid Nehlig