What Does Soda Do to Your Stomach? Experts Weight In

How bad is soda for your health? Here's everything you need to know.

Rebecca Valdez is a registered dietitian nutritionist who's passionate about food justice, equity and sustainability. She empowers clients to advocate for their own health while practicing gentle nutrition and compassionate self-care. She approaches nutrition counseling through a cultural, individualized and weight-inclusive lens.

Maria Laura is EatingWell's senior nutrition & news editor. As part of the nutrition team, she edits and assigns nutrition-related content and provides nutrition reviews for articles. Maria Laura is a trained dietitian, almond butter lover and food enthusiast with over seven years of experience in nutrition counseling.

Soda, like all things, can be enjoyed in moderation. And while it's pretty common knowledge that soda isn't the greatest for your health, what really happens to your body when you drink soda? You may have seen various videos online showing how soda can be used to clean pennies, create soda-bottle volcanoes when paired with Mentos mints or even corrode metal. Luckily, the body does have mechanisms that protect your insides from the sweetened, carbonated beverage. However, drinking soda too often can still impact different parts of the body. And according to a 2021 article published in Preventing Chronic Disease, 63% of adults in the U.S. drink soda at least once per day. Here's what to know about the effect of soda on your body, symptoms of drinking too much and alternatives to consider.

According to the CDC, drinking soda frequently is associated with weight gain, obesity, type 2 diabetes, heart disease, kidney disease, non-alcoholic liver disease, tooth decay, cavities and gout. Additionally, adults and adolescents who drink soda frequently are more likely to have less healthy behaviors, including smoking, not getting enough sleep and more screen time.

Drinking soda is associated with tooth decay (dental caries), enamel erosion and tooth loss, per a 2022 study in the journal Biomimetics. "Anything really acidic and anything with a lot of sugar can cause tooth "rot," or decay," says Scott Cardall, D.M.D., M.S. "Soda is quite acidic and usually has high amounts of sugar, which gets turned into lactic acid by plaque and microbes in the mouth and starts to dissolve the teeth."

In addition to damaging your teeth, soda can also impact your oral hygiene in several ways, including changes to saliva and gums. "Saliva plays a crucial role in oral health, as it helps to neutralize the acid in your mouth and wash away food particles and bacteria. However, drinking soda can decrease your saliva production, making it harder for your mouth to fight off harmful bacteria," says Ankit Patel, D.M.D., M.S.D. at 24/7 Dental, "Also, the sugar and acid in soda can irritate and inflame your gums, leading to swelling, bleeding, and even gum recession. If left untreated, gum disease can result in tooth loss and other serious health problems."

While soda may not directly cause damage to the stomach's lining, soda is highly carbonated, which can cause irritation for people who already have digestive issues. "For those with gastritis, ulcers, acid reflux, and the like - the carbonic acid may aggravate symptoms and cause discomfort, especially if you're already experiencing chronic inflammation," says Nancy Mitchell, RN, a registered nurse and a contributing writer at Assisted Living Center.

A 12 oz. can of regular cola soft drink has about 37 grams of added sugar, per the USDA. To put this in perspective, the American Heart Association recommends no more than 100 calories per day (about 6 teaspoons or 25 grams) for women and no more than 150 calories per day (about 9 teaspoons or 36 grams of sugar) for men.

"Soda can pack a powerful punch when it comes to its effect on blood sugar. Rapidly absorbed, added sugar from a soda can quickly spike blood sugar for many people. The body's insulin production may surge in response, attempting to bring the high blood glucose level back down. This pattern of erratic spikes and drops in glucose levels through the day may lead to a trend of high glycemic variability or dramatic glucose swings and fluctuations," says Heather Davis, M.S., RDN, LDN, a registered dietitian nutritionist with Nutrisense. "High glycemic variability can contribute to energy fluctuations and fatigue, mood swings, and even increase the risk for prediabetes, diabetes and cardiovascular disease. Over time, microvascular damage may take place, which some researchers [such as a 2020 article in Cardiovascular Diabetology] believe can negatively impact cardiovascular health," adds Davis.

High amounts of added sugar can increase triglycerides and lower good cholesterol in the blood. According to a 2020 study in the Journal of the American Heart Association, adults who drink soda frequently have a 98% higher risk of having low HDL levels ("good" cholesterol) and a 53% higher chance of developing high triglycerides. "If the sugar from the soda is not used for physical activity, the liver will turn sugar into fat (triglycerides)," says Cesar Sauza, RDN, a registered dietitian nutritionist at Healthcanal.com, "It is common to see fatty liver diagnosis in patients with years of regularly drinking soda."

While artificial sweeteners were originally used as a "healthier" alternative, some research has shown that might not be the case. "A study published last year found that artificial sweeteners, such as the ones found in diet sodas, may negatively affect the gut microbiome and glycemic control," says Davis, which was published in 2022 in Cell. "Other research shows a link between artificial sweeteners and an increased risk of metabolic dysfunction such as type 2 diabetes and metabolic syndrome. All things considered, it might be a good idea for most people to limit their consumption of such beverages and opt for less risky alternatives."

As noted by the CDC, drinking soda frequently is associated with an increased risk of several medical problems, including obesity, diabetes, increased blood pressure, excess abdominal fat, metabolic syndrome and kidney damage and disease.

Symptoms that you may be drinking too much soda may include:

Studies show that drinking large amounts of soda, or at least 10 fl oz., may irritate your stomach due to its high acidity. However, there is no evidence that it damages or causes changes in your stomach.

Drinking soda does not change the size of your stomach, so it mostly likely will not change or shrink if you stop drinking it.

The organ most affected by drinking soda is the mouth. Since soda passes through the mouth first, its sugary and acidic content reacts with the bacteria already present in the mouth, which can cause damage to the enamel and promote cavity-causing bacteria and contribute to tooth decay.

Soda impacts your insides by damaging your oral hygiene, irritating your stomach and changing your gut microbiota. Because of its high added sugar content, it can contribute to a myriad of health problems associated with high added sugar intake, including metabolic syndrome, diabetes and cardiovascular disease.

It is a popular home remedy to consume flat soda, usually cola, ginger ale or clear sodas, to ease an upset stomach. However, there's no evidence that soda is good for your stomach.

Soda is refreshing and tastes good, and is a commonly enjoyed beverage among Americans. However, drinking it frequently is associated with adverse health effects, from oral health to cardiovascular health. Drinking too much at once can also cause immediate discomfort or stomach irritation. If you're craving soda but worried about the impact on your health, consider a healthier, less-risky alternative, such as flavored seltzer, kombucha or sparkling tea.