Gas (Flatulence)

What is Gas and Flatulence?

Gas and flatulence mean an accumulation of gas in the digestive tract that is released through the rectum as flatulence or through the mouth as belching. It often causes a sensation of bloating and abdominal distension.^[1] Passing some gas each day is normal, and it becomes a concern when it is excessive, painful or paired with other symptoms.

Common symptoms

The main symptoms are passing gas, belching, bloating and abdominal discomfort that can range from mild pressure to cramping.^{[1, 2]} Bloating is a feeling of fullness, while distension is a visible or measurable increase in abdominal girth, and the two can occur together or separately.^[3]

Gas itself is mostly odorless. Smell comes mainly from sulfur-containing compounds that some foods produce, a general fact we include for context.

Causes and risk factors

Improper eating habits are among the most common causes of flatulence.^[1] Swallowing air, for example by eating quickly, can contribute to belching, but aerophagia (air swallowing) is rarely symptomatic on its own.^[4]

Gas is also produced when bacteria in the colon ferment food that was not fully digested. Food intolerances such as lactose intolerance cause bloating, abdominal pain and flatulence after the problem food.^[5] Other contributors include a previous infection that changed the gut bacteria, heightened gut sensitivity and slowed transit through the bowel.^[2] Bloating and distension are linked with both functional and organic digestive disorders, such as irritable bowel syndrome, functional dyspepsia and constipation.^{[2, 3]}

How it is diagnosed and treated conventionally

For persistent bloating and gas, diagnosis starts with a history and physical examination. In functional bloating, if there are no alarm signs or relevant findings, further tests are unnecessary.^[3] Tests are used when the history points to a specific cause. Breath tests may be used to look for lactose intolerance or bacterial overgrowth.

Treatment begins with changing eating habits and avoiding triggers.^[1] Depending on the cause, doctors may suggest a low FODMAP diet, probiotics, antispasmodics such as peppermint oil, or other drugs.^[3] Simethicone, an over-the-counter anti-gas agent, is widely used for bloating and flatulence and is not absorbed into the body.^[6] For supragastric belching, a review found that education and behavioral treatment can be effective.^[4]

Why Gas and Flatulence calls for a whole-person approach

Gas symptoms are not caused by one thing. Food, gut bacteria, gut movement, sensitivity to normal gas volumes and stress can all contribute.^{[2, 3]}

Complementary care therefore looks at digestion, eating habits and stress together, while testing for the underlying cause stays with your physician.

Food and fermentation

Some foods are more fermentable than others, and which ones cause trouble differs from person to person. A network meta-analysis of 13 trials found a low FODMAP diet ranked first for global irritable bowel symptoms, abdominal pain and bloating, although most trials were in specialist settings and did not study reintroducing foods.^[7] This diet should be supervised by a dietitian.

Gut sensitivity and movement

Visceral hypersensitivity, abnormal gut movement and disordered coordination between the diaphragm and abdominal wall are thought to contribute to functional bloating and distension.^[3] This means the amount of gas does not always match how bad the symptoms feel.

Stress and the gut-brain connection

Stress changes gut movement, secretion, pain perception and the gut's bacteria, and it is linked with several functional digestive disorders.^[8] People often notice more gas and bloating during stressful periods, which is a reason stress management is part of supportive care.

Constipation and slow transit

Delayed passage of stool through the bowel is one recognized cause of bloating and distension.^[2] Addressing constipation is therefore often part of managing gas.

Acupuncture for Gas and Flatulence

What the research shows

We found no clinical trials of acupuncture for gas or flatulence itself. Evidence comes from related digestive conditions and is mixed.

In a sham-controlled trial of 278 people in China with meal-related functional dyspepsia, 12 acupuncture sessions over 4 weeks produced a higher response rate than sham acupuncture (83% vs 52%). Upper abdominal bloating was one of the three symptoms measured. The authors noted that the trial lacked objective outcomes, had a high dropout rate and could not blind the acupuncturists.^[9] A Cochrane review of seven functional dyspepsia trials found only low or very low quality evidence and could not say whether acupuncture is more effective or safer than other treatments.^[10]

For irritable bowel syndrome, a meta-analysis of 17 trials found no improvement over sham acupuncture in symptom severity or quality of life in the sham-controlled trials. Acupuncture did better than medication and no treatment in trials without a placebo control, which the authors suggested may reflect patient preference or expectations.^[11] A meta-analysis of 61 trials in functional gastrointestinal disorders found more symptom improvement with acupuncture than with sham, medication or no specific treatment, but rated the evidence moderate or low quality.^[12]

How acupuncture may work

Researchers propose that electroacupuncture influences gut movement through the nervous system, including the enteric nervous system and neurotransmitters. Some of this work comes from animal studies in rats.^[13] These are proposed explanations, not established mechanisms, and they have not been studied in gas or flatulence.

What treatment involves

Treatment uses fine, sterile, single-use needles placed at points on the abdomen, legs, arms and other areas, usually left in place for about 20 to 40 minutes. A course is typically several visits. The dyspepsia trial used 12 sessions over 4 weeks, and we reassess after a short course to see whether symptoms are changing.^[9]

In prospective studies, about 9 in 100 patients had a minor reaction such as brief bleeding, soreness or redness at a needle site, and serious events occurred in about 1 in 10,000 patients.^[14] Tell the practitioner first if you have a bleeding disorder, take blood thinners, are pregnant, or have a pacemaker (relevant to electroacupuncture).

Ayurvedic medicine for Gas and Flatulence

The Ayurvedic view

In Ayurveda, gas and bloating are traditionally linked with Vata, the principle said to govern movement, and with weak digestive fire (agni) that leaves undigested material (ama). Gaseous distension of the abdomen is called Adhmana in the classical texts. These are traditional frameworks for choosing care, not biomedical diagnoses.

Therapies that may be used

Care is chosen for the individual and traditionally combines:

• Regular, warm, freshly cooked meals eaten slowly, in a calm setting, and avoiding very cold or carbonated drinks
• Digestive spices used traditionally for gas, such as ginger, cumin, fennel, ajwain and asafoetida, and triphala, prescribed individually
• Gentle movement, abdominal massage and relaxation practices

Panchakarma is not appropriate during pregnancy, acute illness or frailty, and it should not replace a medical evaluation of persistent gas. Product quality matters for any Ayurvedic preparation, because about one fifth of those bought online contained detectable lead, mercury or arsenic in one study.^[15]

What the research shows

We found no clinical trials of Ayurvedic medicine for gas or flatulence, so the evidence is none. A review of triphala, a traditional three-fruit formula, discusses its possible role in lower digestive symptoms in functional bowel disorders. It is a literature review that recommends further clinical studies, and it does not show benefit for gas.^[16]

Herbal medicine for Gas and Flatulence

Herbs and formulas that have been studied

No herbs have been tested specifically for gas. Related research covers peppermint oil in irritable bowel syndrome, and peppermint and caraway oil, the herbal preparation STW5, turmeric and others in functional dyspepsia.^{[17, 18]} Ginger, a traditional digestive herb, has been reviewed for gastrointestinal disorders.^[19]

What the research shows

The evidence for related symptoms is limited. A meta-analysis of 10 trials with 1,030 patients found peppermint oil better than placebo for overall irritable bowel symptoms and abdominal pain, with more side effects and very low quality evidence.^[17]

A Cochrane review of 41 trials in functional dyspepsia found that some herbs may improve symptoms, including peppermint and caraway oil, with certainty ranging from moderate to very low.^[18] A review of ginger trials found benefit for nausea but too few studies to judge other digestive disorders.^[19] None of these studies measured gas as the main outcome.

Safety and herb-drug interactions

Herbs are active substances and can interact with medicines. Reported interactions include enhanced anticoagulation or bleeding when danshen, garlic or ginkgo were combined with warfarin, and bleeding when ginkgo was combined with aspirin.^[20] In one study, peppermint oil caused more side effects than placebo.^[17] Tell us if you are pregnant or breastfeeding, have liver or kidney disease, or have a known food allergy. Herbs should come from tested sources and be prescribed individually.

Translating traditional medicine into modern biological language

This section is interpretation, not equivalence. Chinese medicine often describes bloating and gas as stagnation of qi, or weakness of the spleen and stomach. Researchers studying functional bloating measure gut movement, sensitivity to normal gas volumes and the gut-brain connection, which loosely parallel this picture.^{[3, 13]}

Ayurveda's aggravated Vata and weak agni may loosely correspond to ideas about gut motility and fermentation by gut bacteria, which researchers also study.^[2] No study has shown that these traditional concepts correspond to specific biological processes.

How this care fits with your medical care

Complementary care here works alongside your physician. We do not diagnose the cause of gas or test for lactose intolerance, celiac disease or bacterial overgrowth, so ongoing or new symptoms should be medically evaluated. Do not stop or change prescribed medicines or begin a restrictive diet without professional guidance.

Please bring any diagnosis, breath test or lab results, a food and symptom diary, and a full list of medicines and supplements.

When to seek urgent medical care

Gas is usually harmless, but some accompanying symptoms need prompt medical assessment.^[3]

• Severe or worsening abdominal pain
• Blood in the stool or black stools
• Persistent vomiting, or vomiting with a swollen abdomen and no passage of stool or gas
• Bloating that comes with fever or yellowing of the skin

If any of these occur, call 911 or go to the nearest emergency department. See your physician promptly for unexplained weight loss, a sudden change in bowel habit, diarrhea that lasts for weeks, or bloating that is persistent and getting worse.