What are the most common causes of gas in the digestive system?

Most of the time they form gas in the stomach and intestine it is due to something the person ate or drank. One of the main causes is the consumption of carbonated drinks and the intake of some foods. Some diseaseseven some medicines, can contribute to the formation of gas in the digestive system. Gases can be quite uncomfortable, cause pain and can cause you some other embarrassing situation but the most important thing is that they are not usually harmful. Even so, severe and prolonged cases should be reported to the doctor because they can sometimes be a symptom of a larger problem.

A healthy digestive system contains billions of bacteria of numerous species in the gut They live in symbiosis with the human body. Some of these bacteria produce gases as a waste product after metabolizing the remains of undigested food. In the digestive system there are also bacteria that consume and metabolize these gases and produce other types of waste substances that are eliminated with the feces. The balance between the bacteria present in the intestine has a very important role in the amount of gas expelled by the human body. In this balance, the diet and digestive health.

The drink and the food

The most common cause of intestinal and stomach gas is intake of more gas than usual. This gas can be ingested contained in food and drinks or swallowed when swallowing. For example, carbonated drinks contain high amounts of dissolved carbon dioxide (a gas). Gum and hard candy also make gas worse as they tend to be swallowed more frequently due to increased salivation while sucking and chewing. Excessive gas intake also occurs when you eat too much, eat quickly, or don't chew well before swallowing.

Many people experience bloating and flatulence after drinking milk or to eat dairy products. This is due to inefficient or incomplete digestion of lactose, the sugar in milk. Lactose digestion is even less in people with some degree of lactose intolerance. Undigested lactose passes to the colon where there are bacteria that metabolize it and produce gases in the process. For similar reasons, a high fructose diet (fruit sugar) can cause high gas production in the intestines of some people as well as starchy foods (potato, corn, etc.).

The very fatty foods they can also lead to this problem as they take longer to fully digest. This means that the bacteria have more time to metabolize the food in the intestine. Eating fewer foods rich in fat also promotes faster gastric emptying, helping to reduce the feeling of bloating.

increase the fiber intake It's healthy, there's no doubt about it, but can increase gas production in the intestine. But not all fiber has the same effect. Beans and legumes in general, cabbages, cauliflower or cabbage are among the foods whose fiber produces more gases (and more smelly). But this does not imply poor digestion of these foods as is normally believed, on the contrary, these vegetables are not indigestible at all. If the increase in fiber consumption is done gradually, we will give time for the digestive system and the population of bacteria that lives in it to accommodate the greater amount of fiber and gas production will be less intense.

Diseases that cause flatulence

Some diseases and disorders of the gastrointestinal tract often present with the appearance of a greater volume of gases in addition to symptoms such as swelling, spasms and cramps, pain or diarrhea. Among these diseases we can mention irritable bowel syndrome, ulcerative colitis or Crohn's disease. Some infections, such as gastroenteritis, can also produce a high amount of gas in the stomach and intestine.

In the case of chronic diseases, such as irritable bowel syndrome, the symptoms can persist even when medical treatment is being followed and the diet has been modified. This is due to the fact that chronic alterations of the digestive system interfere with the normal digestion process and the treatment of these diseases is usually quite difficult, in fact people who suffer from any of these diseases usually go through several different treatments as well as dietary changes until achieve control of symptoms.


Some types of medication can alter digestion and cause gas and flatulence. This is the case of antibiotics. Some antibiotics upset the balance of naturally occurring bacterial populations in the intestine. This is especially the case with broad-spectrum antibiotics, those that kill many different species of bacteria and also affect some of the species that live in our intestines. Other medications that cause gas are some used in the type 2 diabetes treatment by blocking the digestion of carbohydrates.

When the problem is caused by antibiotics, the symptoms will disappear after the end of the treatment as the intestinal bacterial flora re-establishes itself. Taking probiotic supplements or yogurt with live ferments for a few days can help improve the alteration of the digestive system by promoting the repopulation of the bacterial flora.

When to go to the doctor

In most cases, excess gastrointestinal gas is due to simple and harmless reasons, such as a change in diet and eating habits. However, some causes are more serious and therefore it is recommended that anyone who suffers from gas for more than one or two weeks, accompanied or not by other symptoms, see a medical professional. Most serious causes of gas are accompanied by severe stomach pain, blood in the stool, fever, vomiting, or chest pain.

If the doctor sees signs that there may be a serious disorder behind the gases, the most common thing is to request diagnostic tests such as blood tests, stool tests or imaging tests (X-ray, ultrasound, MRI, etc).

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