With irritable bowel syndrome (IBS) symptoms like cramping and running to the bathroom a lot, you may not be aware of related problems that aren't causing obvious discomfort. For example, food is passing through your gut before you can absorb needed nutrients.
Malabsorption of Nutrients
The most common IBS symptom is abdominal pain, according to the International Foundation for Gastrointestinal Disorders (IFGD). You're also likely to have diarrhea or constipation, often going unpredictably from one to the other and back.
When you have diarrhea, food moves too quickly through your digestive tract. When you have constipation, it moves too slowly. "Both disrupt the average time to process nutrients," says Niket Sonpal, MD, a gastroenterologist and adjunct assistant professor of clinical medicine in the department of basic biomedical sciences at Touro College of Osteopathic Medicine in New York City.
When your body isn't processing its food properly, you could be missing out on some very important nutrients, including iron and vitamin B12. Without these two in particular, you could become anemic, according to the American College of Hematology. Anemia can cause fatigue because your blood isn't carrying enough oxygen to your cells.
"Your doctor can test your blood to check for any nutrient deficiencies," Dr. Sonpal says. If deficiencies are found, your doctor may prescribe supplements, either pills or, in more severe cases, injections, to make up for them. Still, he says, "the easiest thing to do is to avoid any foods that trigger a flare-up of your IBS."
You also want to eat smaller meals that are rich in nutrients that your body needs, be sure you're getting enough fiber in your diet and identify and practice stress-reduction techniques that work for you, according to the IFGD. Depending on the severity and type of IBS you have (diarrhea dominant or constipation dominant), your doctor also might recommend medications, says Mayo Clinic.
Help From a Low-FODMAPs Diet?
Another way to relieve IBS symptoms and ward off a problem with malabsorption is to identify triggers by eliminating FODMAP foods from your diet, says Kelly Krikhely, RD, CDN, clinical nutrition coordinator at Mount Sinai Hospital in New York City.
FODMAP is the acronym for fermentable oligosaccharides, disaccharides, monosaccharides and polyols — short-chain carbohydrates and sugar alcohols that are poorly absorbed in the small intestine, explains the IFGD. Because FODMAPs are poorly absorbed, they rapidly ferment in the large intestine, and fermentation can cause gas and bloating.
According to Stanford Health, some common FODMAP foods are:
- Fructose, found in some fruits, honey and high-fructose corn syrup
- Lactose, the sugar in milk
- Fructans (inulin), found in wheat, onion and garlic
- Galactans, found in beans, lentils and legumes
- Polyols, found in artificial sweeteners such as sorbitol, mannitol, xylitol and maltitol and in fruits with pits, such as avocado, apricots, cherries, nectarines, peaches and plums
Most FODMAPs are naturally occurring in foods. (Some, such as artificial sweeteners, are used as additives.) Typically, these foods do not cause symptoms, "but consumed in high enough doses, they can lead to symptoms in those who are susceptible," Krikhely says. "Not everyone with IBS will react to lactose-containing foods, but it can be problematic for some people. The same holds true for all FODMAP foods — it is very individualized, specific to each person."
Some people try a low-FODMAP diet to see if it eases symptoms. But following one is complex and best administered with the assistance of a registered dietitian, Krikhely says. "During the elimination time period, there is a long list of foods that need to be avoided, making it difficult to meet all your nutritional requirements," she says. This could cause you to become malnourished.
"This is why it is very important that this diet is not maintained indefinitely," Krikhely says. "It is a short-term tool that can help identify foods you may not be tolerating." The IFGD recommends 6 to 8 weeks at most for the elimination phase. Then slowly add these foods back into your diet, Stanford Health says.
Is This an Emergency?
- Niket Sonpal, MD, gastroenterologist, adjunct assistant professor of clinical medicine, department of basic biomedical sciences, Touro College of Osteopathic Medicine, New York
- International Foundation for Gastrointestinal Disorders: “Symptoms of IBS”
- American College of Hematology: “Anemia”
- Kelly Krikhely, MS, RD, CDN, clinical nutrition coordinator, Mount Sinai Hospital, New York City
- International Foundation for Gastrointestinal Disorders: “Treating IBS Pain”
- International Foundation for Gastrointestinal Disorders: “The Low FODMAP Diet Approach”
- Stanford Health: “What is the Low FODMAP Diet?”
- Mayo Clinic: "Irritable Bowel Syndrome: Diagnosis and Treatment"