Causes of smelly flatulence can range from harmless to potentially severe. It may not always be easy to identify what is behind smelly flatulence due to the number of potential causes.
Many reasons for smelly flatulence revolve around food or medication. However, some causes may indicate an underlying health condition.
The following are some of the more common causes of smelly flatulence:
- intolerance to food
- high fiber in food
- bacteria or infections
- colon cancer
Intolerance to food
Food intolerance is a very common cause of bad odor flatulence.
Typical conditions that can cause smelly flatulence include lactose and gluten intolerances. In both of these conditions, the body’s inability to break down lactose or gluten causes smelly gas to build up and eventually be released.
Other people may have food intolerance due to a disease such as celiac disease.
Celiac disease is an autoimmune disease that causes injuries to the digestive tract. People with celiac disease have difficulty digesting gluten, which is found in wheat products.
A person with celiac disease may also experience:
- weight loss
If a person suspects food allergies or intolerances, they should see a doctor to test for these conditions. This will help find the exact cause and allow the person to avoid foods that contain the offending ingredient.
Food high in fiber
High-fiber foods are difficult to digest. Although very good for people’s overall health and well-being, these slow-digesting foods break down or ferment in the digestive tract. The fermentation process produces odorous gas.
In some cases, foods higher in fiber have a distinctive odor. The natural odor from these foods can also cause flatulence to be smelly.
Some foods that may cause odors include:
High-fiber foods often also contain more sulfur than other types. This can cause the makeup of a person’s fart to change to include more sulfur, which has a distinct odor and will cause the person to produce smellier gas.
Certain medications can cause someone to produce smelly gas as they are digested.
One of the more common culprits is antibiotics. Antibiotics may kill off some of the healthful or “good” bacteria in the digestive tract while they work to destroy an infection.
The removal of the good bacteria causes an imbalance in the digestive tract. The imbalance can cause a person to produce bad smelling gas. This excess gas can also lead to uncomfortable bloating and constipation.
Constipation occurs when stool builds up in the colon or large intestine and cannot exit. This may be due to taking certain medications, poor diet, or other biological causes.
The buildup of stool in the colon often causes a buildup of smelly gases to occur alongside. This extra gas may cause bloating and discomfort. When finally released, the gas is often smelly.
Bacteria and infections
The digestive tract is responsible for breaking down foods into usable nutrients, which are absorbed into the blood. It also produces waste, which is passed through the colon.
The digestive tract relies on several different components to do this, including its resident good bacteria.
At times, the levels of bacteria in the digestive tract may become imbalanced, potentially leading to an infection. The infection will often cause:
- smelly, excessive gas
- pain in the abdomen
When a person experiences any of these symptoms, they should consult a doctor as soon as possible.
Though not as common, a person may experience excessive smelly gas due to the presence of cancer of the colon. Cancerous polyps or tumors can form blockages that cause gas to build up in the intestine.
One early warning sign is when changes in diet or medication do not stop foul-smelling gas from occurring.
After 50 years of age, a person at average risk for colon cancer should be tested to check for colon cancer.