Why do my farts smell so bad?

Flatulence, which is sometimes called passing wind, passing gas, or farting, is a biological process that helps to release gas from digestion. Though in some cases they are silent and odorless, farts can become uncomfortable when they are loud and foul smelling.

Smelly gas is not uncommon and is often considered normal. Some foods or medications can cause excessively smelly farts. There are, however, some instances where smelly farts can be an indicator of an underlying infection, digestive issues, or a disorder.

6 smelly flatulence causes

There are a number of reasons why your farts smell bad. In most cases, foul-smelling flatulence is associated with the foods you eat and an unbalanced diet. However, there can be more serious causes of rotten-smelling gas.

1. High-fiber foods

Many high-fiber foods can make you pass more gas. It takes longer for these foods to break down in your digestive system, so they ferment over time.

High-fiber foods also sometimes smell, which means your farts may smell too. This is especially true with strong-smelling vegetables such as:

Your gas may smell like rotten eggs because of the sulfur in fiber-rich foods. Sulfur is a natural compound that smells like spoiled eggs. Many vegetables are sulfur-based.

If this is causing your flatulence, a simple change in diet will be sufficient treatment.

2. Food intolerance

If you have a sensitivity or reaction to certain foods, your gas could have a foul odor. For example, people with lactose intolerance can’t break down the carbohydrate lactose. As a result, it is fermented by bacteria in your gut.

Gluten intolerance, or in its more severe form as Celiac disease, can also cause smelly farts. Celiac disease is an autoimmune disease where there is an immune response to the protein gluten. This leads to inflammation and injury in the intestine, leading to malabsorption. Flatulence can be a result of this.

Other than bad-smelling flatulence, Celiac disease can cause other symptoms:

Talk to your doctor to get tests and determine if you have any food allergies or sensitivities that may be making your farts smell.

3. Medication

Although uncommon, certain medications can cause smelly flatulence. Antibiotics kill off harmful pathogens in the body. They also destroy some of the good bacteria in your stomach, which aids digestion. Without this good bacteria, your gas may smell. You could also experience bloating and constipation.

Treatment for this cause involves changing medication, which you should not do without talking to your doctor first.

4. Constipation

Constipation indicates that you have a buildup of stool, or poop, in your colon. If you can’t poop regularly, it can cause bacteria and odor to develop. The end result is foul-smelling and sometimes painful gas.

Taking over-the-counter laxatives can be a simple home remedy for constipation.

5. Bacteria buildup and digestive tract infections

When your body digests food, it extracts nutrients and sends them to the bloodstream. The waste products are sent to the colon. Disrupting the digestion process can cause an overgrowth of bacteria.

Some bacteria can cause infection in the intestines and digestive tract. This may cause a higher volume of gas than normal and a strong-smelling odor. People with digestive tract infections also often have abdominal pain and diarrhea.

Visit your doctor to determine if you have a bacterial infection. If you do, they will prescribe antibiotics to clear the infection and get you well.

6. Colon cancer

A more rare cause of smelly farts is colon cancer. When polyps or tumors form in the digestive tract, it can cause a partial bowel obstruction, which results in gas buildup and bloating.

If you begin to experience abnormal smelling gas and discomfort, and a change in diet or medication doesn’t affect your symptoms, call your doctor for full evaluation. They can determine whether a colonoscopy is warranted. Treatment for colon cancer varies based on the stage of cancer. It can include surgery to remove tumors and chemotherapy to kill cancer cells.

When to see a doctor

In most cases, having foul or odorless flatulence is no cause for alarm. However, if your gas is accompanied by irregular symptoms, you should visit a doctor immediately. Some adverse symptoms you may experience alongside smelly gas include:

Prevention

Flatulence is natural and necessary to dispose of waste and gas in the body. There are some things you can do to get rid of smelly farts: