Gas

GUT GUIDES

Gas is defined as the upward expulsion of air from the digestive tract through the mouth, in the form of a burp or belch, or the downward expulsion of air through the anus, in the form of flatulence. Burping, belching, and flatulence are normal bodily functions, but when they happen in excess, they can signal that something is amiss in the digestive tract. There’s a distinction between the two types of gas: “good” gas and “bad” gas. Beans and cruciferous vegetables contain potent cancer-fighting compounds and healthy fiber, but they also contain an indigestible carbohydrate that may cause gas. Bad gas, on the other hand, represents feedback from your digestive system and can be a sign of an unhappy GI tract and a clue that you may be eating or drinking something that your intestines are having trouble digesting. Gas may also be a cause of bloating, as bloating is essentially the buildup of gas (or in some cases stool) in the GI tract.

SYMPTOMS

  • Burping or belching
  • Flatulence
  • Bloating
  • Wet gas

CAUSES

Good Gas

Beans and cruciferous vegetables like cabbage, cauliflower, kale, and broccoli contain an indigestible carbohydrate called raffinose. Bacteria in the colon ferment raffinose and produce methane, which you may experience as smelly gas. This is considered good gas, because it’s accompanied by the health benefits that eating those foods confer.

Bad Gas

Bad gas is most often caused by lactose intolerance, fructose malabsorption, or the consumption of low-calorie sweeteners.

Other causes of excessive gas include:

  • Aerophagia (air swallowing)
  • Dysbiosis
  • Hormones
  • Celiac disease
  • Osmotic cathartics
  • Artificial sweeteners
  • Fruit juices
  • Carbonated drinks
  • Excessive sugar intake

DIAGNOSIS

Excessive gas is a symptom, not a medical diagnosis, and the story behind the gas symptom is most helpful in arriving at a meaningful diagnosis. If you are not able to eliminate your gas with lifestyle adjustments, seek help. Make sure that the information you give your doctor or healthcare practitioner is complete with all the details. If you feel your gas is caused by something you are eating or lifestyle choices, pay close attention to the feedback your GI system gives you to help you arrive at the root cause(s) of your gas—take note of what foods, drinks, and lifestyle choices make you feel good and what choices aggravate your digestion. Over time, you’ll likely figure out the adjustments you need to keep your GI tract functioning without symptoms of gas.

TREATMENT

The guidelines below may also help you treat the root cause(s) of your gas.

Good Gas Lifestyle Modifications

Avoiding “good gas” foods altogether is not recommended because they contain important nutrients. Here are some things you can do to cut down on the gas when eating them:

  • Start with a small amount and gradually increase your serving size to let your body get acclimated to them.
  • Add lemon juice to your good gas veggies to stimulate digestive enzymes.
  • Soak beans overnight before cooking them.
  • Avoid canned beans, which not only tend to cause more gas, but may also contain a chemical called bisphenol A (BPA) in the can lining, which has been linked to cancer and other conditions.
  • Cook beans with a sea vegetable like kombu, which makes beans more digestible because it contains the enzyme needed to break down raffinose.
  • Take Beano or Bean-zyme at the start of a meal. Like kombu, these products contain a plant-derived enzyme that breaks down raffinose.
  • Eat a pinch (about half a teaspoon) of fennel seeds or chew on a stalk of raw fennel at the end of a meal to benefit from its gas-reducing oils. You can also make fennel tea by steeping a teaspoon of crushed seeds or fresh fennel bulbs in a cup of boiling water for 10 minutes, or you can add it to salads or cooked dishes.
  • Boost your GI tract’s population of “good” bacteria by consuming fermented foods like kefir that contain actively growing essential bacteria and helpful yeast species that result in decreased gas production.

Bad Gas Lifestyle Modifications

Identifying and reducing potential sources of bad gas can help in eliminating your gas and in turn, your bloat. Here are some suggestions:

  • Eliminate dairy for a couple of weeks to see if you may be lactose intolerant or consider a breath or blood test to confirm the diagnosis.
  • Avoid high fructose corn syrup, to ensure you’re within the daily limit of fructose absorption of about 50 grams and choose more natural sources of fructose like fresh fruits and vegetables over the fructose in processed food and soda. Avoid unexpected sources of fructose, such as applesauce, dried fruits, cereal, fruit juices, and salad dressings.
  • Choose calories over gas when it comes to sweeteners. Low-calorie sweeteners made of sugar alcohols aren’t absorbed in the small intestine and produce a lot of gas when they undergo additional fermentation by bacteria in the colon, and studies have shown they’re bad for your gut bacteria.
  • Cut down on sulfur-rich foods like eggs, meat, yogurt, and seafood.
  • Consider trying the FODMAPS diet that minimizes poorly absorbed short chain carbohydrates, including most dairy, corn syrup, wheat products, certain vegetables, and fruit with a high glucose-to-fructose ratio such as watermelon and dried fruit.
  • Exercise

In addition to dietary modifications, regular exercise can offer benefits in relieving your gas symptoms. Yoga is especially beneficial, as the twisting poses can help disperse gas pockets and relieve pressure.

Burping, belching, and flatulence are normal bodily functions, but when they happen in excess, they can signal that something is amiss in the digestive tract.
Dr Robynne Chutkan
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