Dear Dr. Blonz, Please forgive the indelicacy of this question, but what is a good approach to the problem of intestinal gas? B.I., San Jose, Calif.
Dear B.I.: After we swallow, the foods we have eaten get exposed to a series of enzymes and churning actions designed to break down large, complex nutrients into sizes small enough to be absorbed through the tiny portals along the walls of the digestive system. That which is not absorbed travels on to the large intestine and waits in queue for elimination. This bulk includes such non-digestible items as bran and other fibers, bits of food and phytochemicals the body does not handle well, and any other components the body might have had trouble digesting. Our intestinal flora, composed of microorganisms that inhabit our large intestine, now have a chance to devour these compounds -- in fact, that's what they live on. Gases are produced as a byproduct of their action. Some gas can be absorbed back into the body, but if the rate of production exceeds that ability, the passing of gas will result.
A normal, healthy individual will pass gas an average of 10 times per day, and most of the gas produced does not present an assault to the senses. Some gaseous compounds are on the other end of the spectrum, and when you add ten grams of a nonabsorbable carbohydrate, the type that flora feast upon, the incident of gas passing can rise substantially. With any increase comes the awareness of the bloating and the need to let it out.
The gassy nature of foods, however, can vary from meal to meal, and depend on portion size, timing and other factors such as how often we eat a particular food, whether we're relaxed or anxious, the speed at which we eat, or even how completely we chew. The best bet is to keep track, as best you can, of the foods and any coincident factors to find out which combinations give rise to the undesired effects.
A large bowl of beans on an empty stomach, eaten by someone who doesn't eat them very often, will produce more gas than the same serving eaten slowly as a part of a full meal by a regular bean-eater. Having a combination of protein, fat and carbohydrate tends to slow the rate at which food travels through the digestive system. In this case, gas absorption into the body can keep up with production. By contrast, when a single gassy food is eaten, the flora are able to go one-on-one with the problem-causing material and the results will be more obvious.
Key foods include legumes, as they contain a type of carbohydrate that the body has trouble digesting. Lactose in dairy products can also be a problem. Note that there are over-the-counter products that can help with these two types of foods. Sorbitol and other sugar alcohols, and certain soluble fibers in grains or laxatives can also be a problem.
Although foods are the first thing people think of with intestinal gas, other factors also need to be considered. These include medications, especially antibiotics, laxatives and the inadvertent swallowing of air, often occurring when eating too quickly or talking while chewing and swallowing. Health problems with the digestive system itself can also be an issue. Stress, anxiety and smoking can also affect efficient digestion. Any persistent digestive problem should be brought to the attention of your health professional.
I recommend a read of the page from the National Digestive Diseases Information Clearinghouse at http://tinyurl.com/3og8t.
Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to firstname.lastname@example.org. Due to the volume of mail, personal replies cannot be provided.