Sulfur burps and diarrhea are an unpleasant combination of digestive symptoms that often signal an underlying gastrointestinal issue. The burps have a distinct, foul, rotten-egg smell caused by a specific gas produced during digestion. Diarrhea involves passing loose, watery stools, indicating the body is struggling to properly absorb water and nutrients. When these symptoms occur together, especially persistently, they suggest an imbalance that is accelerating gas production while impairing normal digestive motility.
Understanding Hydrogen Sulfide Gas
The offensive, rotten-egg odor associated with sulfur burps is caused by the release of hydrogen sulfide (\(\text{H}_2\text{S}\)) gas. This gas is a natural byproduct of digestion, but excessive amounts cause noticeable symptoms. \(\text{H}_2\text{S}\) is generated when specific types of gut bacteria, known as sulfur-reducing bacteria, break down sulfur-containing compounds. These bacteria primarily act on sulfur-containing amino acids and proteins that were not fully digested. An increase in undigested sulfur compounds reaching the lower digestive tract gives these bacteria more material to process, leading to a surge in \(\text{H}_2\text{S}\) production, which then rises through the esophagus.
Dietary and Lifestyle Causes
The most common cause of increased \(\text{H}_2\text{S}\) production and subsequent diarrhea is the consumption of sulfur-rich foods. High-sulfur compounds are abundant in many common ingredients:
- Cruciferous vegetables, including broccoli, cauliflower, and Brussels sprouts.
- Alliums such as garlic and onions.
- Protein sources like eggs, red meat, poultry, and certain dairy products.
These foods contain sulfur-containing amino acids that contribute to gas when broken down.
Certain eating habits can also overwhelm the digestive system and worsen symptoms. Eating excessively large or high-fat meals slows digestion significantly. This delay allows food to sit longer in the stomach and small intestine, giving bacteria more time to ferment and generate \(\text{H}_2\text{S}\) gas. Consuming food too quickly or talking while eating can cause excessive air swallowing, leading to general burping that may carry the \(\text{H}_2\text{S}\) odor.
Fermentable carbohydrates, including artificial sweeteners like sorbitol and xylitol, are another common trigger because they are poorly absorbed and readily fermented by gut bacteria. This fermentation process produces gas, and if the bacteria involved are sulfur-reducers, the resulting gas will contain \(\text{H}_2\text{S}\). Similarly, carbonated beverages and alcohol, especially beer and wine, can increase gas in the stomach and often contain sulfur compounds, contributing to digestive upset.
Underlying Gastrointestinal Conditions
When sulfur burps and diarrhea persist despite dietary modifications, the cause is likely a chronic or acute gastrointestinal condition.
One significant underlying issue is Small Intestinal Bacterial Overgrowth (SIBO), where excessive bacteria colonize the small intestine, a region that should normally have a low bacterial count. This misplaced bacterial population rapidly ferments food before it can be properly absorbed, leading to both the malabsorption that causes diarrhea and the accelerated \(\text{H}_2\text{S}\) production.
Infections are another distinct cause. The parasite Giardia lamblia, contracted through contaminated water or food, infects the small bowel and often results in profuse, watery diarrhea, sulfur burps, and abdominal cramping. The bacterial infection Helicobacter pylori (H. pylori), which lives in the stomach lining, is also linked to increased gas production, bloating, and sulfur burps.
Irritable Bowel Syndrome (IBS), particularly the diarrhea-predominant type (IBS-D), is characterized by chronic motility issues and visceral hypersensitivity. While IBS itself does not directly cause \(\text{H}_2\text{S}\) production, the associated dysregulation of gut flora and rapid transit time can significantly exacerbate the symptoms. Less common causes include conditions that impair fat breakdown, such as gallbladder dysfunction, or disorders that slow stomach emptying, like gastroparesis.
When to Consult a Doctor and Symptom Management
If sulfur burps and diarrhea are frequent, severe, or do not resolve within a few days, medical consultation is warranted to identify the root cause. Several red flags indicate a need for prompt professional attention:
- Persistent watery diarrhea lasting more than two days.
- The presence of blood or pus in the stool.
- Unexplained weight loss.
- Severe abdominal pain, a high fever, or signs of dehydration like decreased urination and a fast heart rate.
Before a diagnosis is made, certain over-the-counter and lifestyle adjustments can help manage immediate symptoms. Staying adequately hydrated with water or electrolyte solutions is important to counteract fluid loss from diarrhea. Temporarily reducing high-sulfur foods may lessen the amount of \(\text{H}_2\text{S}\) produced. Bismuth subsalicylate, an over-the-counter medication, is sometimes recommended as it can bind to hydrogen sulfide gas, potentially reducing the odor and providing short-term relief.
A doctor may order specific diagnostic tests to investigate the underlying cause. A breath test, which measures hydrogen and methane levels, is a common tool used to diagnose SIBO. Stool tests are often used to check for the presence of parasites, such as Giardia, or other infectious agents. Identifying the specific cause through medical testing is the most effective path toward targeted, long-term treatment and symptom resolution.