Why Carbohydrates Tend to Trigger IBS Symptoms, and how to minimise them

While the exact cause of IBS remains unclear, certain foods—particularly carbohydrates, sugars and very healthy foods such as vegetables—are well-known triggers for many individuals. To understand why carbohydrates can exacerbate IBS symptoms, we need to explore two key factors:  gut bacterial balance and the role of brush border of the small intestine.

The Role of Gut Bacterial Balance in IBS Symptoms

The gut microbiome, which consists of trillions of microorganisms living in the digestive tract, plays a critical role in digestion and overall gut health. In individuals with IBS, there is often an imbalance in gut bacteria, a condition known as dysbiosis. This imbalance may lead to the improper fermentation of certain carbohydrates, particularly those classified as fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs).

How Carbohydrates Interact with Gut Bacteria

When undigested carbohydrates reach the large intestine, gut bacteria ferment them, producing gas as a byproduct. In people with IBS, this fermentation process can lead to excessive gas production, causing bloating, cramping, and discomfort.

Inflammation and Gut Barrier Dysfunction

Dysbiosis can also increase gut inflammation and weaken the intestinal barrier, making the gut more sensitive to certain foods, including carbohydrates. This heightened sensitivity exacerbates IBS symptoms.

Digestive Enzymes and the Brush Border

The brush border of the small intestine refers to the microvilli-covered surface of intestinal epithelial cells. This is where digestive enzymes for carbohydrates are secreted. These enzymes convert carbohydrates such as bread, pasta, fruits and vegetables into simple sugars that can be absorbed into the bloodstream. When the function of these enzymes is impaired, carbohydrates remain partially digested, and the digestive system pulls in water to flush it leading to experiences such as cramps and diarrhoea.

Deficiency of Brush Border Enzymes

Individuals with IBS often have reduced levels or activity of brush border enzymes, such as lactase, which is responsible for breaking down lactose (a sugar found in milk), DPP-IV which is for gluten, plus a host of other enzymes that facilitate carbohydrate digestion.

It also leads to malabsorption of FODMAP foods

Many FODMAPs (e.g., fructose, lactose, and polyols) are poorly absorbed in the small intestine due to limitations in enzyme activity or enzyme production. This malabsorption allows them to pass into the colon, where they are fermented by gut bacteria, leading to gas, bloating, and diarrhoea.

When we have low enzyme activity (which can be triggered by a single episode of food poisoning, a virus, or a stressful event such as changing jobs or homes), carbohydrates, especially those high in FODMAPs, can become uniquely problematic.

The combined loss of enzymes and disruption to gut bacterial balance lead to rapid fermentation, producing excessive winds that can overstretch the intestinal walls and cause pain. This is because there are wind-producing microbes and not enough wind-consuming ones. A well-balanced microbiome will both produce and consume wind generated by carbohydrate fermentation

Osmotic Effects

Water is the body’s natural method for digesting carbohydrates – when there is an issue with properly breaking them down, that water becomes excessive, and the result is diarrhoea.

Hypersensitivity:

As the digestive system struggles to break down food, the resulting micro-inflammation injures more microvilli, leading to a gradual cumulative loss of enzyme activity. This results in increasing food sensitivities and a growing list of foods that trigger symptoms. Replacing the enzyme function, along with microbiome support can significantly reduce the irritation and give the gut a chance to recover on its own.

Managing Carbohydrate-Triggered IBS Symptoms

Thankfully, there are strategies to minimise the impact of carbohydrates on IBS symptoms:

1.      Low-FODMAP Diet:

Avoiding foods for a period gives the enzyme producing brush border of the small intestine a chance to recover. This dietary approach involves reducing high-FODMAP foods, such as onions, garlic, wheat, and certain fruits, to identify and eliminate triggers. The trick to reintroducing them is to take a well-rounded supplement that will minimise the workload for the small intestine and get you off a low FODMAP diet within the recommended 6-week limit.

2.      Probiotics

The intensity of IBS will disrupt the balance of microbes in the gut, and beneficial microbes produce enzymes required for digesting some carbohydrates, fibres, fruits and vegetables. Other beneficial microbes will consume the air that the others are producing.  This is why rebalancing the microbiome with a well-targeted probiotic like Cura Sporebiotics, can significantly improve IBS symptoms within a 30-day period.

3Digestive Enzyme Supplements

Digestive enzymes come in all manner of formulas, however for IBS, you need a catch-all enzyme blend that will do the job of the brush border, and also the enzyme-producing microbes that should inhabit it. CuraZyme Tolerance is a catch-all blend, with extra enzymes for lactose and gluten.

4Gradual Dietary Adjustments.

A common mistake for IBS sufferers is that they rush back to normal immediately after their FODMAP period is over. However, the chances of success are greater if you supplement with probiotics throughout and introduce foods gradually with enzymes.

Conclusion

If you suspect that carbohydrates are triggering your IBS symptoms, consider adding Cura Sporebiotics and CuraZyme Tolerance to your routine.

You may be pleasantly surprised by how quickly they work.