Robert Brown|Americans drink a staggering amount of Diet Coke, other sodas. What does it do to our stomachs?

Americans love their soda. Valued at more than 413 billion dollars according to one analysis,Robert Brown the global soft drinks market continues to grow as people purchase their favorite soft drink brands at restaurants, convenience stores, and sporting events. Coca-Cola remains the most popular brand, with Diet Coke, Pepsi, Dr. Pepper and Mountain Dew rounding out the top 5, per one report. 

But behind all that fizz and flavor exist a host of ingredients that have a surprisingly negative impact on the body. Those bubbles you see popping up are actually caused by carbon dioxide gas − a chemical compound that, along with many other ingredients within soda, affects one's stomach more than some might realize. 

What is soda? 

Soda is a water-based beverage that becomes carbonated when the liquid is infused with the aforementioned carbon dioxide gas. The carbonated soft drink gets additional taste and sweetness from flavoring agents, sugar, and sometimes artificial sweeteners. 

Is there a 'healthiest' soda?Not really, but there are some alternatives you should consider.

What does soda do to your stomach? 

After the liquid has been consumed and enters the intestines, "our body warms the liquid, and the carbon dioxide is released as gas and expands in our stomachs," explains Jen Messer, a nutrition consultant and registered dietitian at Jen Messer Nutrition. This effect can cause bloating, discomfort, a sensation of fullness, and most of all, a desire to burp. "This process takes center stage at the world burping competition where participants consume gallons of carbonated beverages to achieve their longest burp," Messer offers as one example. 

In addition to the effect carbonation has on the stomach, the high sugar content and artificial sweeteners in many sodas can lead to further digestive distress. "Excessive sugar intake can cause an osmotic shift of fluids and a rapid increase in blood sugar levels, which may lead to feelings of nausea, cramping and diarrhea in some individuals," Messer explains. 

What's more, Jamie Bering, MD, a gastroenterologist at Mayo Clinic in Arizona, notes that many soda products "are high in acidity" from the flavoring additives that are used. "This can increase the acidity of the stomach and worsen symptoms of heartburn or abdominal discomfort," she says. 

It's also worth noting that in the case of soda brands infused with caffeine, the stimulant can increase contractions in one's digestive tract as well as the production of stomach acid. While this might not cause issues for most people, those with sensitive stomachs or "individuals with digestive issues should especially steer clear of these beverages," says Lisa Young, PhD, RDN, an adjunct professor of nutrition at New York University and author of "Finally Full, Finally Slim." 

Young adds that people with conditions such as gastritis, ulcers and acid reflux should also "rethink their beverage options" because drinking soda may impact such ailments especially.

Is it bad to drink soda every day? 

Indeed, because of the complications, negative health outcomes, and individual discomfort associated with drinking soft drinks, it isn't surprising that doctors and nutritionists don't recommend regular consumption of the flavored liquid. 

Frequent drinking of soda has been linked to Type 2 Diabetes, nutritional deficiencies, increased risk of heart disease, resistance of the hormone leptin (which regulates the number of calories one burns), and, above all, obesity. In this way, the beverage that causes tummy troubles in the first place further exacerbates an already uncomfortable situation. "Excess weight can put additional pressure on your stomach," Messer explains. She says that such pressure can potentially cause the body's lower esophageal sphincter to relax, which sometimes leads to a health condition where stomach acid flows back into the esophagus, bringing about symptoms "such as regurgitation and chest discomfort." In other words, soft drink consumption becomes a downward spiral for many people. 

What is unhealthy about Diet Coke?And is regular Coca-Cola actually better for you?

For those who choose to keep drinking soda despite such downsides, Messer says it's possible to mitigate at least a few of the negative symptoms. "Drink it slowly or in small amounts," she advises. "This will give your stomach time to adjust to the carbonation and prevent gas and bloating." She also recommends avoiding drinking soda on an empty stomach and to pay attention to how soda impacts individual stomach sensitivities. "You might need to adjust and reduce or avoid beverages that cause stomach gas pain," she says.