Passing gas, especially very smelly gas, can be an embarrassing problem. Fortunately, home remedies such as diet and lifestyle changes can often prevent bad-smelling gas.

In most cases, it is natural and healthy for a person to experience intestinal gas. It is not uncommon for farts to be either smelly or produce no odor at all. Health experts typically consider both to be normal.

However, certain foods or underlying health problems may cause a person to regularly pass smelly gas. As such, making certain lifestyle changes or receiving treatment for the underlying condition can help reduce or prevent bad-smelling flatulence.

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A fart, often known as gas or flatulence, is the buildup of gases within the intestines. The causes of these gases include the air a person swallows while eating and from the process of digesting food. Flatulence is the passage of this intestinal gas, known as flatus, through the rectum

It is a normal part of how the body works and often not a health concern. Most people may fart from 5–15 times a day, while others may pass gas up to 25 times a day.

In some cases, farts are silent and pass without much notice. In other cases, they can be loud and smelly. A person may experience some bloating and pressure before releasing gas.

Causes of flatulence vary. There are many foods, medications, and other factors that can affect how much and how smelly gas is in the digestive tract.

Causes of smelly flatulence can range from harmless to potentially severe. Flatulence consists of multiple gases. Typically, the cause of most bad odors from farting is due to intestinal bacteria producing sulfur-containg compounds, such as hydrogen sulfide.

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

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. This 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:

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.

High-fiber foods often also typically 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. Examples of medications that can result in excessive or smelly wind include:


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.

Read on to learn more about constipation and gas.

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
  • diarrhea
  • fever
  • nausea
  • vomiting
  • fatigue

When a person experiences any of these symptoms, they should consult a doctor as soon as possible.

Colon cancer

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 45 years of age, a person at average risk for colon cancer should test to check for colon cancer.

In many cases, a person can try to treat flatulence at home. Often, changes in diet can be enough to reduce or get rid of smelly gas. These changes may require eating less of or avoiding several foods. The foods that need to be reduced or avoided will vary from person to person.

In other cases, an individual may find that medication has caused smelly flatulence. For over-the-counter medications, a person will likely find relief by stopping the product. For prescription medications, it is advisable to speak to a doctor about alternatives if smelly flatulence becomes a problem.

A person will also want to contact their doctor if:

  • they experience additional symptoms, such as persistent stomach ache, bloating, constipation, or diarrhea
  • they are losing weight without trying to
  • there is blood present in their stool
  • changes to medication do not bring relief
  • alterations to diet do not bring improvement

In these cases, the gas may be due to an infection or underlying condition that needs treatment. A doctor can perform tests to find out exactly what is causing the gas and decide a treatment plan for the individual.

For those whose gas occurs from food intake, prevention typically involves changing their diet. A person can try tracking food intake and times when they experience excessive, smelly flatulence. They can then eliminate or reduce the amount of the food or foods that cause excessive gas.

Some tips to avoid excessive gas include:

  • eating smaller portions
  • avoiding trigger foods
  • avoiding naturally smelly foods
  • eating slowly
  • drinking more water
  • avoiding carbonated drinks

Read on to learn more about home remedies for reducing smelly gas.

There are times when the underlying cause may be more severe than the body’s reaction to certain foods or mild constipation. In these cases, stopping the gas will often happen by treating the underlying condition.

Bad flatulence is not always a cause for concern. Most people will find that they can manage bad flatulence at home with changes to their diet.

Others may need to seek out medical advice and attention if their bad flatulence does not clear up after avoiding certain foods or medications. If other symptoms also occur, it may be a sign of infection, which may need medical intervention.

Most people will experience symptom relief once the underlying cause of their flatulence is worked out and treated.

Some FAQs about smelly flatulence may include:

What does it mean if your farts smell really bad?

If a person is experiencing persistent foul-smelling flatulence, this could indicate food intolerances, gastrointestinal problems, or a side effect from certain medications.

What food causes smelly farts?

Foods that may cause smelly farts are those that people may be intolerant to, such as dairy or gluten products, or foods rich in fiber, such as navy beans, broccoli, avocado, and buckwheat.

Is releasing gas good for you?

Flatulence is normal, healthy, and a way for the body to release intestinal gas. As such, it is good for a person to pass gas, particularly if it is causing discomfort. While it is healthy to pass gas, excessive or smelly flatulence could indicate a potential digestive problem.

Why do period farts smell so bad?

A person may notice bad smelling flatulence during their period. This may be due to changes in gut bacteria during menstruation and consuming certain foods, such as dairy and starchy carbs, due to period cravings.