IBS is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. Common IBS symptoms include alternating diarrhea & constipation, indigestion, bloating, flatulence, abdominal cramping, and/or anxiety/depression. The pathogenesis of IBS is not completely clear, but it is known to be multifactorial and complex. Endogenous and exogenous factors such as abnormal GI motility, low-grade inflammation, increased epithelial permeability and visceral hypersensitivity may play a role. Diet and psychosocial aspects are also recognized as important actors. IBS is diagnosed twice as often in women compared to men, and although the condition can be diagnosed at any age, it is most commonly diagnosed in women before the age of 50. IBS commonly develops after intestinal infections and acute or chronic stress.

Furthermore, the interaction between diet and gut microbiota has gained interest as a potential contributor to the pathophysiology of IBS. IBS patients have lower diversity in microbes and microbial shifts that disturb the mucosal lining. This change in gut microbes can influence brain function and increase anxiety & depression in those with IBS.

There are three primary types of IBS:

IBS-D – diarrhea predominant IBS
IBS-C – constipation predominant IBS
IBS-M – mixed IBS

Dietary Recommendations for IBS

Avoid allergenic or intolerant foods; for foods to which there is a mild intolerance rotate every fourth day; avoid gluten and dairy
Avoid coffee, alcohol, diet drinks, artificial sweeteners and spicy foods
Avoid fermentable foodstuffs by following a low FODMAPs diet; it’s not the most intuitive eating plan, but it has been shown to be quite helpful for many with IBS-D
Avoid salads and raw vegetables that may be difficult to tolerate
Limit fruit to 3 servings or fewer daily; 1 serving of fruit = 1 medium piece of fruit or ½ cup chopped fruit
Monitor fiber intake and tolerance
Consume regular meals and moderate portion sizes
Aim to drink 1/2 your body weight in pounds daily, preferably water or caffeine-free drinks; limit carbonated beverages
Drink less than 3 cups of coffee or tea daily
Limit or avoid alcohol
Avoid sugar alcohols

Supplemental Strategies for IBS

Fiber
- Partially hydrolyzed guar gum (PHGG) relieves IBS symptoms in patients at 5–11 gm daily; PHGG can be effective for diarrhea, constipation, bloating, while also help with glycemic regulation, lipid levels, and satiety. PHGG increases the protective butyrate producing bifidobacteria. Two options include Thorne FiberMend and Tomorrow’s Nutrition SunFiber 5-10 gm daily.
- Psyllium fiber has been shown to be immensely beneficial in all types of IBS as it has a bowel-regulatory effect. While I typically recommend 5-10 gm daily, some research suggests 20-25 gm daily. Be sure to drink plenty of fluids. You could use an organic psyllium powder from health food store or if seeking a product, consider Metabolic Maintenance Organic Psyllium Husk Powder or Organic India Organic Whole Husk Psyllium powder.

Probiotics – As noted earlier, probiotics are beneficial bacteria that help to facilitate proper digestion and absorption. Currently, probiotics most commonly studied for IBS include:
- Lactobacillus plantarum 299v
- Bacillus coagulans LBSC (DSM17654)
- Bifidobacterium species - Bifidobacterium lactis & Bifidobacterium infantis
- Saccharomyces boulardii
- Lactobacillus rhamnosus GG

Some reputable comprehensive multi-strain products include SFI Health Ther-biotic Pro IBS Relief, Protren Trenev Trio, Visbiome, and VSL #3. If seeking a solo S. Boulardii product, consider SFI Saccharomyces Boulardii powder, Metabolic Maintenance Saccharomyces Boulardii 10 billion, Seeking Health Saccharomyces Boulardii, or Pure Encapsulations Saccharomyces Boulardii. A great solo Lactobacillus rhamnosus GG product is Pure Encapsulations Pure GG. Pure Encapsulations PureBiOme Intensive is a mix of lactobacillus strains, bifidobacterium strains, and saccharomyces boulardii. Some overall solid broad based probiotic products include Protren Trenev Trio or Natren Healthy Trinity, Biocidin Botanicals Proflora 4R, Designs for Health ProbioMed50, Integrative Therapeutics Pro-Biome, and Metagenics UltraFlora BiomePro.

Vitamin D serum levels play a crucial role in maintaining proper intestinal barrier function and influence the development of IBS. An appropriate increase in vitamin D serum levels has led to an improvement in intestinal barrier function and a reduction in pro-inflammatory factors, such as IL-6 and IL-8. Aim for your serum 25-OH vitamin D levels to be between 40-80 ng/ml. Many benefit from taking 2000-5000 IU D3 daily with a meal.

Glutamine is the primary fuel for the intestinal lining, lymphocytes and macrophages. It is crucial in the healing and repair of damage to the GI tract. This randomized, double-blind, placebo-controlled trial has shown the superiority of adding 15 gm daily glutamine supplementation for 6 weeks to a low FODMAPs diet in amelioration of IBS symptom. There are many clean, l-glutamine powder options on the market. Some options are SFI Health, Thorne, Designs for Health, Vital Nutrients, and Designs for Health.

Peppermint oil promotes antispasmodic activity that is highly effective for reducing abdominal pain. The key here is that it’s enterically coated, so it withstands the stomach acid and release the peppermint oil directly into the small intestine. A common OTC option that you may find effective is IBGard. A cleaner option, though not perfectly clean, is Protocol for Life Balance Peppermint Oil GI.

SBIs (serum bovine immunoglobulins) – SBIs provide support to the intestinal barrier and gut immune health. They have been shown in clinical studies to reduce loose stools and improve stool consistency as well as help with abdominal pain, bloating, and urgency in patients with irritable bowel syndrome with diarrhea (IBS-D); for IBS-C, the results are inconclusive. Additionally, SBIs have been shown to alleviate refractory gastrointestinal symptoms in patients with inflammatory bowel disease (IBD), including nausea and diarrhea. Dosage is 3.5 gm daily. Three options include Designs for Health IgGI Shield, Ortho Molecular SBI Protect Powder, and Micobiome Labs MegaMucosa.

Rifixamin is an oral antibiotic that has shown potential benefits for some IBS-D patients, and has been shown to reduce abdominal pain in patients with IBS. Rifaxamin is a broad-spectrum antibiotic that is not systemically absorbed and has a minimal effect on the gut microbiome. While not my first ‘go-to’ for IBS, it can be included as an option for those with continued IBS struggles

Here’s to a calm, happy, well-nourished GI tract!

In Health,
Natalie