Although renowned for creating delight in children, flatulence is not considered the best way to make friends and influence people. But there is an upside: the production of gas means that your body is hosting the right kinds of bacteria. To encourage these ‘good’ bacteria – known as our microbiome – we need to eat fiber and the right type of starch.
Fermentable components of dietary fiber and starch have a critical role in feeding the gut microbiome. It is fermented down mostly to short chain fatty acids. This process in turn creates gas. So that old childhood limerick about beans does have its basis in scientific fact.
Fermentation is a chemical process that breaks down carbohydrates in fiber: bacteria do it in our bowels to create food for themselves. These molecules improve your overall health. That means the more gas you develop the better your gut is working.
The component in food that manages to make it through digestive processes in the stomach and small intestine to feed the microbiome in the large intestine is known as resistant starch. You can improve the proportion of resistant starch in your diet by consuming more foods such as unrefined whole grains, legumes, unripe bananas and cooked and cooled foods, such as potatoes, pasta and rice.
There have been a number of studies that have shown that increasing a diet with more resistant starches fosters weight loss and early satiety reducing down the need to overeat and graze. Resistant starch is referred to as “skinny carbs.” Resistant starch fuels weight loss by burning both body fat and visceral fat (belly fat), which surrounds your internal organs. This “hidden” fat has been shown in some studies to be a marker of increased disease risk, such as diabetes and heart disease.
Resistant starch also enhances your body’s ability to metabolize nutrients. Because it helps you feel full, you tend to consume fewer calories at each meal—and we all know that taking in fewer calories than you burn is the key to weight-loss success. The benefits of resistant starch do not stop with weight loss. There is compelling scientific evidence that resistant starch can protect against insulin resistance (Type II Diabetes) and some cancers because it reduces chronic inflammation, improves digestion, and there is some new evidence that it has a roll in relieving depression. So while you may follow the skinny carb diet for the weight-loss effects, you will be doing your body a favor in other ways.
There has been some recent clinical studies describing how different dietary components influence the microbiome, and determine their production of not just gas, but also molecules that are beneficial in the large intestine. For example, it is now known that bacteria living in the large intestine produce a short chain fatty acid known as butyrate, which can reduce inflammation by stimulating regulatory immune cells. Now there is real hope for those that suffer from inflammatory bowel disease that diet high in resistant starch can work in conjunction with prescribed medication to greatly improve the condition.
Resistant starch (RS) takes three forms in nature:
RS1 is prevalent in seeds, legumes (beans, lentils, and chickpeas), and unprocessed or partially processed whole grains.
RS2 contains a lot of the carbohydrate amylose. It is packed into dense granules, like RS1, but it is not gelatinized—that is, the starch has not begun to break down and absorb water. For this reason, it yields very slowly to the digestive process, remaining relatively intact until it reaches the lower GI tract. In addition, because amylose is a relatively linear starch, it has fewer branches subject to attack by amylase, so it digests more slowly. You will find RS2 in potatoes, corn (especially varieties bred by starch manufacturers to have high levels of amylose), under-ripe bananas, and flour.
RS3 is another high-amylose starch, but the amylose forms during cooking. RS3 is not susceptible to being broken down by amylase and so is completely resistant. Among the common food sources of RS3 are potatoes, breads, and cereals (like plain rice cereal and cornflakes).
Scientifically, this means that these foods increased the bowel production of butyrate, a short chain fatty acid, which is a biomarker for weight loss and of good bowel health. Researchers at the University of Colorado Health Sciences Center found that eating just one daily meal containing 5 grams of resistant starch increased fat burning by 23 to 25 percent. So there are some good carbohydrates after all.
What foods you choose in the supermarket can have dramatic effects on gut health. Although a good number of these foods will bring about some unpleasant flatulence; this side effect is not long-standing and goes away over time as your body get acclimated to them. It is quite a small price to pay for some big results.