As a registered dietitian, many people ask me questions about nutrition. Most of it revolves around weight loss tips or questions about foods considered "healthy" but I also love to serve as a source of health information, especially when it involves dietary treatments.
I received a question from a friend about Irritable Bowel Syndrome, or IBS, that can be addressed with dietary treatments. Many people simply ignore their symptoms of gas, bloating, alternating constipation and diarrhea. Doctors often use IBS as a catch all for what we like to call in medicine, "non-specific symptoms". Most people think pf their low-grade gastrointestinal symptoms as "that food just doesn't agree with me"; or they ignore them because these symptoms usually appear at times of greater emotional stress.
The intestinal tract is made of two parts: the upper portion, called the small intestine formed of three distinct segments, and the lower intestines, called the colon. Both are highly responsive to emotional stress because they interact with hormone production. For instance, the GI tract is the largest producer of seratonin in the body. Seratonin is a stress reducing hormone that makes us feel relaxed and happy. So, when you eat chocolate, you do feel happier because your brain is happier from all the seratonin it just produced in your gut.
Based on an understanding of our intestines, here are some basic recommendations for treating IBS:
1) Stress reduction with exercise
2) Supplements: take fish oil/omega 3 supplements daily to reduce inflammation. Also consider a Vitamin D/Calcium supplement if you are not outside at least 3o min/day. Take Metamucil every day for additional soluble fiber.
3) Water: drink at least half your body weight in water- try adding lemon or cranberry juice
Dietary strategies for managing IBS are based on a higher-soluble fiber diet and avoiding food intolerances. If this does not work, then try a month-long elimination diet. This is to "rest" your GI system from common intolerances to clear out any overgrowth of bacteria in your GI system which cause excess gas and bloating. Then, after a month, add back in things like yogurt, but only one per week. This helps to add back in healthy bacteria into your colon while identifying true triggers.
The most common cause of IBS is what is called a "fructo-oligosaccharide" intolerance. This is a short-chain carbohydrate molecule that is not broken down as it should be in first part of the small intestine. Instead of that carbohydrate being digested properly, it reaches the colon in its full state, interacting with the bacteria and fermenting, causing gas.
What foods are fructo-oligosaccharides? The most prominent sources in our diet are whole wheat and high fructose corn syrup. These are some dietary recommendations based on the study that explored this intolerance, which was published in an October 2005 article of the Journal of American Dietetic Association:
1) Eat a high soluble fiber diet. Soluble fiber foods including oats, pears, apples and beans regulate the digestive system by forming softer stools.
2) Avoid high fructose foods and trigger foods (which is different for each person)
- avoid whole wheat and use sprouted grain breads
- avoid full fat dairy
- avoid dried fruits and fruit drinks
- avoid high fructose fruit like melons or grapes and eat more berries.
- avoid all processed foods containing high fructose corn syrup.
- avoiding gas producing vegetables (esp in their raw state) like broccoli, raw carrots, raw onions, raw cucumbers, cabbage
- avoid excess caffeine which can trigger diarrhea and accelerate digestion