(there are several myths listed on pg 3-5 so I will share one of them)
MYTH: Got gas? Beans, vegetables and milk are the main culprits. Beans, cabbage, Brussels sprouts, milk, bran. Those are some of the usual suspects when people are trying to figure out why they're experiencing, ahem, gas. Ant those foods can cause gas. But most of us overlook a growing source of the problem: inulin, or chicory root extract, one of the most popular ingredients in "high-fiber" foods. "Of all the fibers added to foods, inulin is the one that probably causes the most intestinal gas, " say fiber expert Joanne Slavin, professor of nutrition at the University of Minnesota. "Inulin contains sugars that our digestive enzymes can't break down." The enzymes do just fine with sugars that have only one or two basic units (called saccharides). Sucrose, or table sugar, for example, is a disaccharide, that is broken down in the small intestine into fructose and glucose. But when it comes to sugars made up of three or more units - often called oligosaccharides - our enzymes are useless. So the sugars end up as food for the bacteria in the gut. "Inulin is quickly and completely fermented in the large intestine," explains Slavin. And when your bacteria finish fermenting it, you get stuck with the gas they give off. "Beans are notorious for causing gas because they have sugars like raffinose and stachyose," notes Slavin. Raffinose has three sugar units. Stachyose has four. "If you look at literature on treating or cooking beans to make them less gassy, it's mostly t get the oligosaccharides out of there," she adds. (Beano tablets can prevent gas because the contain an enzyme that breaks down raffinose and stachyose). Whether inulin is a problem depends on how much you eat and who you are. "Our review of studies found that inulin is generally well tolerated at levels up to 15g a day," says Slavin. But at around 20 grams, flatulence or bloating is more likely. "So does is a big issue and there is also individual variability."
Each serving of FIber One 90 Calorie Bronies, Fiber One cottage Cheese and Yoplait LIght with fiber has 5 grams of fiber and much of it is inulin. Some Fiber One Chewy Bars have up to nine grams. "If you have a serving of beans you'll get about 3 grams of oligosaccharides, not nine grams," says Slavin. "Any they're more manageable in a real food because they're digested more slowly and usually mixed with other foods."
Another hidden source of gas: sugar alcohols like sorbitol and maltitol. "They're low-calorie carbohydrates because they're not completely digested and absorbed," explains Slaving. "Typically if you are eating sugar-free candy or gum, your exposure to sugar alcohols is low, but if people eat the whole bag of candy, it can cause gas." Sugar alcohols aren't all equal, though. In small studies, some people complain of gas when doses of sorbitol reach 10-20g but few complain unless they get at least 30-40 grams of maltitol. Most foods don't have that much. Breyers Vanilla or chocolate CarbSmart and No sugar Added ice creams, for example, have 4-5 g of sorbitol per half cup, but many people start at a whole cup. And Baskin Robbins No sugar Added Caramel Turtle Truffle ice cream has 25grams of maltitol per scoop..
Of course, some people may eat more than one food with sugar alcohols during the course of a day. And people vary. "Most people can tolerate normal doses, but not everybody is the same," say Slavin.
On the plus side, sugar alcohols have fewer calories than sugar and inulin spurs the growth of Bifido bacteria, which may be good for gut health (that's why it is called a prebiotic). But the more bacteria in your gut, the more gas they give off.
"Scientists argue that gas isn't bad for you, but most people say it's not acceptable," say Slavin. "If you hve gas, you should definitely consider what you're eating. If it's a lot of fermentable fiber or sugar alcohols, that could be the explanation."