I RECENTLY TOOK an online WebMD quiz titled “All About Farts” and failed miserably — to my surprise, because gas is an issue to which I’ve paid considerable attention over the years. (I’m taking advantage of WebMD’s story title as permission to employ the word “fart,” instead of the medical “flatus,” with abandon.)
What I learned from my quiz errors: Air travel can make you fart, because air pressure can make gas worse if you’ve recently eaten whichever foods make you gassy; a person eating a normal diet passes gas 13 to 21 times a day; foods high in carbs are more likely to produce gas compared with those higher in fat or protein (more on this below); anti-gas medications such as Gas-X use enzymes that help break down sugar, which helps food get digested more easily; and the best way to get rid of a fart is by opening a window — not lighting a match.
The few answers I got right: Bad-smelling farts do not mean you’re sick; exercise can help you fart less by getting rid of extra air in your system; gassiness increases with age because your digestive system slows down; and chewing gum can make you gassy, as can anything that causes you to swallow air, including fizzy drinks and eating too fast.
The main cause of gas is the breakdown of food in the digestive system. Although different foods cause gas in different people, most notorious gas-producers are among the healthiest, plant-based foods, such as beans, fruits, vegetables and whole grains. More obvious villains are sugary foods, such as cakes, soft drinks and candy — and anything made with high-fructose corn syrup.
Lists of high gas-producing foods vary, and elimination diets are the best way to determine which foods are the gassiest for you. Before embarking on those, digestive issues can be minimized by taking smaller bites, chewing thoroughly and eating slowly — to make it easier for the stomach to break down food; and by drinking liquids beforehand rather than during the meal, because too much liquid can dilute stomach acids and disrupt digestion. On the other hand, eliminating high-gas foods, which are often high in fiber, can cause constipation, in which case drinking more water is advised.
Gas-causing foods are grouped under the acronym FODMAP, referring to a collection of molecules that are poorly absorbed in some people, according to Kris Gunnars on the Authority Nutrition website. (FODMAP stands for Fermentable Oligo-, Di-, Mono-saccharides and Polyols.)
FODMAPs generally pass through most of the intestine unchanged until they reach the far end, where they are broken down, or fermented, by a certain kind of gut bacteria that produces hydrogen (instead of methane, produced by most by bacteria). Hydrogen can cause gas, bloating and sometimes pain. (In contrast, low gas-causing foods are digested earlier, primarily in the stomach.) FODMAPs are osmotic, meaning they pull water into the intestinal tract, which also slows digestion.
Sadly, the high-FODMAP list includes some of the most delectable foods: artichokes, apples, mangos, bananas, garlic, onions, breakfast cereals, milk, ice cream and chocolate. Most high-fiber foods are on this list, so low-FODMAP diets can create their own digestive issues. Oatmeal is an exception: It’s low in FODMAPs but high in fiber.
The best way to figure out which FODMAPs are causing an individual’s gas is to start with a six-week low-FODMAP diet, eliminating almost everything from dairy and gluten to many fruits and vegetables, after which foods can be added one at a time back into the diet. The Stanford University Low-FODMAP diet avoids fructose (fruits, honey); lactose (dairy); fructans (wheat, garlic); galactans (beans, lentils) and polyols (artificial sweeteners, along with “stone fruits” including avocadoes, cherries and peaches). At the end of six weeks, add high-FODMAP foods one at a time to identify personal triggers.
An alternative is to start by eliminating “The Top 10 Vegetables That Cause Gas,” from Flatulence Cures, which can be divided into several groups: Peas and beans have high levels of soluble fiber and oligosaccharides, and produce mostly odorless gas; broccoli, cabbage, cauliflower and Brussels sprouts are high in sulfur compounds, which can produce the rotten-egg gas smell; and onions, asparagus, mushrooms and artichokes have an array of different gas-producing compounds. (Meat can also cause unpleasant-smelling gas.)
“Cruciferous” vegetables, such a broccoli and cauliflower, can be digested more easily if they are eaten regularly to build up intestinal tolerance; and a mix of vegetables is less likely to cause problems than a large plate of just one kind, according to flatulencecures.com. Low gas-producing vegetables include carrots, tomatoes, zucchini and leafy greens like spinach — and, beneficial as always, kale — although these sometimes appear on FODMAP-villain lists as well.
Also recommended on Flatulence Cure are daily probiotics; fennel, ginger or peppermint tea; activated charcoal, and finally, a broad- spectrum digestive enzyme called Veganzyme ($49.95), to be taken just before a “potentially hard to digest meal”— if you are good at anticipating such things. (Read listed warnings on all products.)
If all this sounds like too much work, the last quiz question I got wrong asks what to do if you feel a fart coming on. I checked “sit down and clench muscles.” The right answer is “stand up and relax everything.”