Nausea is a common, unpleasant symptom of many temporary illnesses, often accompanied by the urge to vomit. A long-standing cultural belief suggests that drinking flat cola or another sugary soda can help soothe an upset stomach. This home remedy has been passed down through generations, leading many to keep a bottle of cola on hand. To determine if this practice has any scientific basis, it is important to examine the history of this belief and the actual components of the beverage.
How Cola Became a Folk Remedy
The association between cola and stomach relief dates back to the late 19th and early 20th centuries, when carbonated drinks were first marketed. Early versions of cola were sold in pharmacies, often dispensed at soda fountains, and were advertised as a patent medicine capable of curing various ailments, including indigestion and headaches. This connection to pharmaceutical settings helped establish a perception that these sugary beverages possessed medicinal properties.
The practice of “flattening” the soda—stirring it to remove the carbonation—also became a common instruction. This step was taken to make the drink gentler on a sensitive stomach, as the intense fizziness of a fresh soda was thought to cause discomfort. The original Coca-Cola syrup, before being mixed with carbonated water, was even sold over the counter for the relief of nausea and vomiting, reinforcing its status as a trusted household remedy.
Analyzing Cola’s Ingredients for Therapeutic Value
The perceived effectiveness of cola can be traced to a few of its main components, which theoretically address certain aspects of nausea. One factor is the high sugar content, which provides readily available glucose that can potentially settle the stomach, especially if the nausea is related to low blood sugar. However, the extremely high concentration of sugar in commercial colas is far more than what is needed and can actually draw water into the digestive tract, potentially worsening diarrhea.
Another ingredient is phosphoric acid, an inorganic compound that gives cola its tartness and acts as a preservative. This acid is the active ingredient in some over-the-counter anti-nausea medications, which are formulated as a balanced solution of sugar, fructose, and phosphoric acid. While this might suggest a therapeutic effect, the concentration of phosphoric acid in a standard cola drink is significantly lower than the amount found in these pharmaceutical anti-emetics, making its benefit minimal at best.
The carbonation itself also plays a role in the remedy’s reputation, as the gas bubbles can encourage belching. For some people, burping may temporarily relieve feelings of fullness or pressure that accompany certain types of stomach upset. However, the carbon dioxide gas can also increase bloating and gastric distension, which can aggravate the feeling of sickness.
Medical Consensus on Cola for Nausea
Despite its cultural popularity, most medical professionals do not recommend cola or other sugary carbonated beverages for treating nausea and vomiting. The primary concern is that the high sugar and low electrolyte content of these drinks is counterproductive to rehydration efforts. When experiencing vomiting or diarrhea, the body loses both fluid and electrolytes like sodium and potassium.
Consuming a beverage with a very high sugar concentration can pull water out of the body’s tissues into the intestine, exacerbating fluid loss and potentially worsening dehydration. Major health organizations recommend against using fruit juice or carbonated drinks, including cola, as alternatives to proper oral rehydration solutions (ORS). The carbonation may also contribute to bloating and discomfort, or trigger acid reflux, which can counteract any perceived benefit.
Hydration and Dietary Alternatives for Upset Stomachs
The most important step in managing an upset stomach is preventing dehydration by maintaining fluid and electrolyte balance. The most effective approach for fluid replacement is sipping small, frequent amounts of an Oral Rehydration Solution (ORS), which contains a carefully balanced ratio of water, sugar, and electrolytes. Clear broths, non-caffeinated herbal teas, and water are also suitable options for general hydration.
For dietary relief, bland foods are generally recommended because they are easy to digest and do not irritate the stomach. These include the components of the BRAT diet (bananas, rice, applesauce, and toast), as well as plain crackers or boiled potatoes. Natural remedies with scientific backing include ginger, which contains compounds like gingerols that help block serotonin receptors in the gut that trigger nausea. Peppermint can also offer relief, as its active compound, menthol, helps relax the smooth muscles of the gastrointestinal tract. If a person is unable to keep any liquids down for an extended period, or if symptoms persist beyond 48 hours, consulting a healthcare provider is necessary.