What is IBS?
1. IBS stands for Irritable Bowel Syndrome. One should not confuse it with Inflammatory Bowel Disease (IBD), which includes Crohn’s disease and Ulcerative Colitis.
2. IBS is one of the most common conditions seen by gastroenterologists and primary-care physicians. According to statistics, it affects between 10 and 15% of the population worldwide. Interestingly, IBS is more common in women than in men and is commonly diagnosed before the age of 50 years.
3. IBS is characterized by a cluster of symptoms: abdominal pain, bloating, excessive flatulence, and altered bowel habits (diarrhea, constipation, or both). Although there is no structural damage to the intestines, these symptoms greatly affect one’s quality of life.
4. There are a number of other diseases that have these same gastrointestinal symptoms, which makes IBS difficult to diagnose. Indeed, it is important to have a diagnosis from a gastroenterologist before starting any dietary therapy as there is a risk of misdiagnosing. For instance, diseases that could mimic IBS are IBD, celiac disease, endometriosis, and others.
5. The cause of these symptoms is still not clear and likely to be due to several mechanisms, with a complex interplay of physiological, psychological, and dietary factors.
There are a number of therapies available: drugs, dietary approaches, and psychological therapies. Combining different tactics may optimize symptom resolution. Indeed, in recent years, there has been a major shift toward a more holistic approach with a focus on dietary therapies.
Why the Low FODMAP Diet?
1. The Low FODMAP diet was developed by researchers at Monash University in Australia as they gathered evidence from numerous studies that IBS symptoms improved after the restrictions of certain carbohydrates. In order to describe them, they created the term “FODMAP”:
- Fermentable
- Oligosaccharides
- Disaccharides
- Monosaccharides
- Polyols
2. FODMAPs are present in many healthy foods:
- Sugars such as fructose (the main sugar in fruit) or lactose (the main sugar in milk)
- Fibers (oligosaccharides) found in wheat, onions, beans, and other foods
- Sugar Alcohols (or Polyols) such as sorbitol and mannitol, found in some fruits, vegetables, and sugar-free foods (gums, candy)
3. In people with IBS, these carbohydrates are poorly absorbed or not absorbed at all. As such, they draw water and travel to the large intestine, where our friendly bacteria ferment them, leading to excessive gas production, bloating, abdominal pain, and other symptoms.
4. The Low FODMAP Diet is not a life-long diet. On the contrary, the strict low FODMAP phase, or elimination, only needs to be followed until symptoms are resolved. Although the length varies with individuals, it typically lasts 2-4 weeks. As it eliminates many nutritious foods, if followed long-term, this diet may lead to nutritional deficiencies and other problems.
5. The good news is that not all people are sensitive to all these foods. Indeed, through a systematic re-introduction under the guidance of an expert dietitian, each person can find out which foods are triggers for them.
Ultimately, the goal is for IBS patients to liberalize their diet and create a personalized diet that includes as many foods as possible while remaining mostly symptom-free.
Want to learn more?
Check out more Low FODMAP Diet Basics
Antonella Dewell, MS, RDN | IBS Resolution Expert
Antonella Dewell is a registered dietitian and IBS specialist based in California. She has over 2 decades of experience working in clinical research at Stanford. Since 2018, she has been running a private practice. She helps people with IBS gain real, lasting relief from IBS symptoms in just 2-4 weeks without giving up all the foods they love, so they can stop feeling anxious around food and get back to fully enjoying food and life again.
