Part 1 – What Causes BLOATING

 Wondering why it’s tough to button your pants sometimes even though your weight has been stable? We don’t mean the distention you get from the sheer volume of a feast you just consumed. We’re referring to the “What gives?” feeling you get when you need to add slack to your belt. It may be because of belly bloating!

“Bloating” is used to describe either a look or sensation in the abdomen, most often referring to a sense of gassiness or distention.¹ Feelings of tightness or pressure in your midsection are also symptoms of bloating.² If your belly distention is located higher, just below your ribs, see the highlight at the end of this article about stomach distention.* 

Solid Food

It is no surprise that it is common to experience bloating after a meal.³ All that food doesn’t stay in your stomach very long and has to go somewhere. If you don’t “go,” that food material backs up. Fatty meals are slowly digested and stay in the gut longer. Whether you are constipated or just full, the expanding presence of residue in the large bowel contributes to abdominal fullness.

Water

When you eat, digestive juices and liquids get drawn into your stomach and small intestine for digestion, which may cause you to feel bloated. Also, after you eat certain foods, there may be a greater shift of water (called osmosis) that increases fluid in the large bowel.^{4, 5, 6} Additionally, bloating can be caused by water retention, often the result of a higher intake of sodium.

Stress & Anxiety

Psychosocial distress may contribute to the perceived severity of bloating.² In one study, women with anxiety or depressive symptoms reported bloat more often than those without these emotional symptoms.⁷ Tension and stress may also cause the intestinal muscles to tighten much in the same way they cause your hands or jaw to clench.

Gas Production

The biggest culprit in bloating may be an overproduction of gas from intestinal fermentation.^4,5 Everyone produces a little gas. You’re supposed to! It’s a sign that the colonic bacteria in your colon are doing their job to metabolize remaining undigested material. Typically, the gas is passed throughout the day. However, if you produce too much gas, or you don’t eliminate it completely, then the abdomen can swell and leave you feeling doughy.

Dairy

Many people feel discomfort in their bellies after they eat dairy products. If you’re lactose intolerant or sensitive to dairy, you may notice that milk products cause you to feel bloated. Don’t think that milk products are a problem for you? Remember that some people develop lactose intolerance as they age.

Sorbitol

This type of sugar, often referred to as a sugar alcohol, is not well absorbed during digestion in the small intestine and can pass into your colon, where it ferments and causes bloating, gas and cramps in some people. Sorbitol is most often found naturally in fruit and as a sugar replacement in chewing gum. It is also used in sugar-free candy, frozen desserts, chocolate, bakery products and some packaged diet foods.

Fructose & Fructans

Fructose and Fructans (basically fructose molecule chains) may be partially unabsorbed and passed on to the colon where bacteria rapidly ferment them, causing abdominal bloating.⁴ Fruit is typically our primary source of fructose sugar, followed by table sugar and high-fructose corn syrup.

FODMAPs

Standing for fermentable oligosaccharides, disaccharides, monosaccharides and polyols; FODMAPs are short-chain sugars that can be easily fermented by gut bacteria to create gas, which can contribute to abdominal bloating.⁴ Raffinose, one such FODMAP, is common in beans. Other FODMAPs that have a reduced effect on blood sugar are found as sugar replacements.⁶

Fiber

In addition to preventing constipation and lowering blood cholesterol, fiber contributes to gas production because it is not digested by enzymes in the small intestine. Instead, the colonic bacteria feast on fiber, which can leave you with a bad case of bloat and flatulence. So it makes sense that foods with added fiber like chicory root (inulin) or resistant starch can contribute to gas and cause bloating.⁸

*Stomach distention is caused by built-up pressure in the stomach from swallowing air, drinking carbonated beverages and the breakdown of certain foods, such as melon, apples, onion, cucumber and bell peppers. Burping releases this excess air, and some foods, such as peppermint, oregano oil and cinnamon, can help you burp more easily. Another way to stimulate burping is to “fight fire with fire” by drinking carbonated water and massaging the area just below your ribs in a gentle upward motion to force a burp.

1. Pathophysiology, Evaluation, and Treatment of Bloating: Hope, Hype, or Hot Air? BE Lacy, SL Gabbard and MD Crowell. Gastroenterology & Hepatology, November 2011.  7(11): 729-739.
2. Understanding Gastrointestinal Distress: A Framework for Clinical Practice. B Spiegel et al. American Journal of Gastroenterology, March 2011. 106(3): 380–385.
3. Bloating and Functional Gastro-intestinal Disorders: Where are we and where are we going? P. Iovino, et al. World Journal of Gastroenterology, October 2014. 21; 20(39): 14407-14419.
4. The FODMAPs Approach — Minimize Consumption of Fermentable Carbs to Manage Functional Gut Disorder Symptoms. Kate Scarlata, RD, LDN. Today’s Dietitian, August 2010. 12(8): 30
5. Small intestine bacterial overgrowth: clinical strategies. A Siebecker. September 17, 2011. Webinar
6. Digestive tolerance and postprandial glycaemic and insulinaemic responses after consumption of dairy desserts containing maltitol and fructo-oligosaccharides in adults. F Respondek, et al. European Journal of Clinical Nutrition, 2014. 68: 575-580.
7. Gastrointestinal Symptoms Before and During Menses in Healthy Women.  MT Bernstein, et al. BioMed Central, Women’s Health, 2014. 14:14.
8. Gastrointestinal tolerance and utilization of agave inulin by healthy adults. HD Holscher, et al.  Food & Function, June 2014. 5(6):1142-9.
9. Abdominothoracic Mechanisms of Functional Abdominal Distension and Correction by Biofeedback. E. Barba, et al. Gastroenterology, April 2015. 148(4): 732–739.