Dietary Solutions for Irritable Bowel Syndrome (IBS)

Kathryn Adel December 9, 2019 SFW

If you have chronic digestive symptoms (constipation, diarrhea, gas, bloating, stomach pain, etc.), the first thing to do is consult with a doctor to investigate the cause and eliminate the possibility of a serious health problem (celiac disease, inflammatory bowel diseases, cancer, parasites, etc.). Keep into consideration that sometimes starting a new medication or supplement can cause digestive upset. An increase in the level of stress can also be a major trigger.

Irritable bowel syndrome (IBS) is defined according to the Rome IV criteria, in which a person could be diagnosed with IBS if they have experienced recurrent abdominal pain on average at least once a week during the previous three months that is associated with two or more of the following:

• Related to defecation;
• Associated with a change in stool frequency;
• Associated with a change in in stool form or appearance.

The timing of symptoms can sometimes be an important clue to the cause of symptoms. If digestive symptoms occur immediately after consuming a specific food, this typically signals an allergic reaction rather than an intolerance. When digestive symptoms occur soon after a meal (approximately 15 to 90 minutes), this may be caused by an acceleration of gastrocolic reflex. Large portions, meals high in fat and food high in roughage can contribute to stimulating this reflex. Finally, when the symptoms occur after the food has had time to reach the intestine (about 2 to 8 hours), they can be caused by malabsorption of some sugars in the intestine.

Sometimes, simple changes to one’s diet may be enough to resolve the symptoms. For example, a lack of fiber or dehydration can cause constipation, and coffee consumption can cause diarrhea in some people. It should be noted that even decaffeinated coffee can cause diarrhea due to its chlorogenic acid content that stimulates the intestinal transit. Here are some simple tips to try if you have symptoms of diarrhea or constipation.

Symptoms of constipation

• Hydrate yourself sufficiently
• Increase your dietary fiber intake (minimum 30 g per day)
• Increase your consumption of foods high in soluble fiber (oatmeal, ground flaxseeds, chia seeds, kiwi, barley, legumes, psyllium, Metamucil, etc.)

Symptoms of diarrhea

• Eat smaller meals more often (rather than 3 large meals a day) to reduce the stimulation of the gastrocolic reflex
• Avoid foods that are high in fat and added sugar
• Avoid foods that can irritate the digestive system such as spicy foods, some artificial sweeteners, alcoholic beverages and coffee
• Reduce your intake of foods that are high in insoluble fiber and roughage such as salads, popcorn, and fruit and vegetable peels
• Choose foods that are high in soluble fiber and also low in roughage such as oatmeal, oranges, sweet potatoes without peels, kiwis and chia seeds.

If simple changes to your diet are not helpful to reduce your gastrointestinal symptoms, other dietary approaches may be considered to help determine the cause of your symptoms and fix the issue.

The FODMAP approach

FODMAPs are fermentable carbohydrates that may be partly responsible for the symptoms in people with IBS. These sugars can be poorly digested and accumulate in the small intestine. Digestive symptoms associated with FODMAP intolerance usually occur approximately two to eight hours after ingestion of foods high in FODMAPs. An intolerance to lactose, fructose, or polyols usually causes gas, bloating, and diarrhea, whereas an intolerance to fructans and GOS usually causes gas, bloating, and constipation. Stools can be lighter in color, cause a burning sensation, float in the toilet, or wake up people during the night. It should be noted that the total intestinal transit time between the moment a food is eaten and the moment when the residual waste is eliminated can take up to 72 hours. Therefore, even though FODMAP-sensitive symptoms usually occur two to eight hours after eating a meal, they can also last up to three days.

The FODMAP approach has been shown to be effective in reducing IBS-related digestive symptoms in approximately 75% of cases. It is also possible to take digestive enzyme supplements to promote the digestion of certain FODMAPs when the cause is a lack of enzymes. The lactase enzyme allows the digestion of lactose, the alpha-galactosidase (Beano) enzyme allows the digestion of GOS and the xylose isomerase enzyme allows the digestion of fructose. On the other hand, there are no enzyme supplements for the digestion of fructans and polyols. It is important to choose a supplement that contains the FODMAP-specific enzyme you are sensitive to, and to take the supplement at the right time.

In some cases, other dietary factors may be the cause of digestive symptoms. Here are a few possibilities.

1) Congenital Sucrase-Isomaltase Deficiency (CSID)

Congenital sucrase-isomaltase deficiency (CSID) is a genetic disorder that occurs when the body can not produce the sucrase-isomaltase enzymes required for the digestion of sucrose and maltose, which are two types of sugar. Sucrose is found in fruits, cane sugar (table sugar), maple syrup and in many foods that contain added sugars, while maltose is found in cereal products. Malabsorption of sucrose typically causes symptoms of gas, bloating, and diarrhea that occur approximately two to eight hours after ingestion of foods containing sucrose. Often, digestive symptoms can get worse if you follow a low FODMAP diet. The treatment for this condition is dietary restriction of sucrose and using an enzyme supplement named Sucraid. It should be noted that this enzyme supplement must be refrigerated.

2) Histamine intolerance

Histamine is a compound known for its role in the immune response of the body to foreign proteins, specifically the allergic response, which can trigger a cascade of inflammatory reactions. Histamine is produced by the white blood cells of our body called mast cells, but is also present naturally in many foods. The amount of histamine in foods may be inherent to the food or depend on external factors such as the stage of ripening and its’ storage, processing method and origin. On a daily basis, small amounts of histamine help regulate functions throughout the body. Hypotheses suggest that histamine intolerance may be caused by a lack of enzymes or increased production of endogenous histamine, but the exact cause remains unknown. If histamine levels in the body are elevated for any reason, eating foods rich in histamine can trigger various symptoms that can vary from person to person. People may have digestive symptoms (stomach aches, bloating, diarrhea, reflux) but also other types of symptoms such as a tightness in the throat or chest, heart palpitations, headaches, dizziness, fatigue, hot flashes, hives, itching or food allergies. Generally, symptoms can occur immediately after eating a trigger food or later (about two to four hours after). Sometimes, the symptoms may vary according to the seasons of the year. Foods high in histamine include tomatoes, spinach, avocados, strawberries, cherries, aged cheeses, cold cuts, fermented foods, wine, beer, meat, poultry and fish as well as certain spices. If you suspect that you have a histamine intolerance, you should consult a medical specialist (gastroenterologist or allergist) and a Registered Dietitian who is specialized in gastrointestinal health.

3) Bile acid malabsorption

Bile acid malabsorption is the cause of several gastrointestinal problems, the main one being chronic diarrhea. This condition may occur as a secondary effect to the removal of the gallbladder (in approximately 9% of cases), SIBO, certain diseases (Crohn’s disease, chronic pancreatitis, bowel resections) or taking certain drugs such as Metformin (a diabetic medicine). Possible symptoms include gas, an urgency to defecate (including at night), light-colored diarrhea, vitamin B12 deficiency, and unexplained weight loss. Diarrhea can occur more severely several hours after eating a high-fat meal, and symptoms usually worsen if people decide to follow a ketogenic diet. Up to 25% of people diagnosed with IBS featuring diarrhea (IBS-D) suffer instead from a bile acid malabsorption. Treatment for this condition involves taking a medicine (a bile acid sequestrant) that usually works very quickly (about three days after the start of its use).

4) Type A2 beta-casein intolerance

Certain people may be intolerant to type A2 beta-casein, which is a variant of a type of protein found in cow’s milk. In this case, symptoms usually occur fairy rapidly following the ingestion of dairy products and may include diarrhea, constipation, gas, bloating, or severe abdominal cramps.

In conclusion, it is important that you determine the precise cause of your digestive symptoms in order to find the appropriate solution to correct them. If you need help determining the cause of your symptoms, do not hesitate to consult with a Registered Dietitian specialized in gastrointestinal health.

Author

Kathryn Adel

Kathryn holds a Bachelor Degree in Nutrition as well as a Bachelor and a Master Degree in Kinesiology, all from Laval University. She is a Registered Dietitian and active member of the Ordre professionnel des Diététistes Nutritionnistes du Québec (ODNQ) and of the American Academy of Nutrition and Dietetics. She holds the Monash University's certification for the FODMAP diet and IBS, and has considerable clinical experience in that area. She is also an accomplished athlete, having ran track and cross-country at a national level. Kathryn specializes in sports nutrition, weight loss, diabetes, as well as heart and gastrointestinal health.