It’s in the rice we eat, the noodles we slurp, and the buns we savour. Gluten, a protein found in wheat and barley, is a part of many foods around the world, including Asia. For some people, however, this seemingly harmless ingredient causes serious health issues. Known as gluten intolerance or non-celiac gluten sensitivity (NCGS), this condition affects millions in ways that are still being explored by researchers.

The science behind gluten intolerance¹

For most people, gluten is harmless. It gives structure to dough, helping bread to rise and become fluffy. But for a growing number of individuals, gluten isn’t just an ingredient—it’s a trigger for a range of uncomfortable and sometimes debilitating symptoms. Unlike celiac disease, a well-known autoimmune condition where gluten consumption causes damage to the small intestine, gluten intolerance doesn’t show up in the same way. There are no obvious markers, such as blood tests or gut damage, and symptoms can be varied and inconsistent. It’s a puzzle for both doctors and patients.

In the world of gluten intolerance, symptoms can range from bloating, fatigue, and headaches to joint pain, skin rashes, and even mood disturbances. Diagnosing the condition is a complex process, usually involving the elimination of other possible causes like celiac disease or irritable bowel syndrome. Many individuals only discover they have gluten intolerance after enduring months or even years of unexplained symptoms.

Intestinal permeability (leaky gut) and gluten intolerance

One theory that has gained attention in recent years is the role of intestinal permeability, often referred to as "leaky gut," in gluten intolerance. The concept of leaky gut suggests that the lining of the small intestine becomes damaged, allowing harmful substances like undigested food particles, toxins, and pathogens to "leak" into the bloodstream.

This disruption in the intestinal barrier may trigger an immune response, which could contribute to the symptoms associated with gluten intolerance. While leaky gut has not been definitively proven to be the cause of gluten intolerance, many believe that it may make the body more susceptible to gluten's effects by increasing systemic inflammation. In turn, this could lead to symptoms beyond the digestive system, such as joint pain, skin issues, and even mood disturbances. However, further research is needed to understand the exact relationship between gluten intolerance and intestinal permeability.

The debate: Is it all in our heads?

Despite the increasing number of people reporting gluten intolerance, the condition remains controversial in the medical community. Some researchers believe gluten intolerance is real, with many patients reporting improved symptoms after eliminating gluten. Others remain sceptical, suggesting that the symptoms could be linked to other factors, like stress or the brain-gut connection, rather than gluten itself.

One of the challenges in understanding gluten intolerance is that there are no clear medical tests, unlike celiac disease, which can be diagnosed with specific blood tests and biopsies. As a result, diagnosis is often made by process of elimination, leaving many patients frustrated and confused.

The role of the gut microbiome²

Emerging research has highlighted an interesting link between gluten intolerance and the gut microbiome—the community of bacteria and microbes that live in our digestive system. Studies suggest that people with gluten intolerance often have an imbalance in their gut bacteria. This imbalance may make the digestive system more sensitive to gluten, triggering symptoms like bloating, pain, and fatigue.

Although scientists are still exploring the exact relationship between the microbiome and gluten sensitivity, the evidence is growing. This research could one day offer more definitive answers about why some people react negatively to gluten and why others don’t.

The growing popularity of gluten-free diets

Over the last decade, gluten-free diets have gained popularity worldwide, including in Asia. While many people adopt gluten-free eating habits believing it will improve their health or aid weight loss, for those with gluten intolerance, it’s not a trend—it’s a necessity.

In many parts of Asia, wheat-based products are ubiquitous. From Chinese chow mein noodles to Indonesian mie goreng, gluten is often found in local dishes. This poses a particular challenge for people with gluten intolerance who live in regions where wheat is commonly used in everyday meals.

For Minh, finding alternatives was key. He learned how to enjoy his favourite meals by swapping traditional wheat-based noodles for rice noodles or choosing rice paper over wheat flour for making spring rolls. However, eating out or travelling still proves difficult. “I have to ask for special accommodations in restaurants, and not all places understand what gluten is,” he explains. “It’s definitely a challenge, but I’ve learned to plan ahead.”

Looking to the future

As research into gluten intolerance continues, there is hope that clearer diagnostic tools and better treatment options will emerge. Scientists are focusing on the genetic, environmental, and dietary factors that contribute to gluten sensitivity, as well as the potential role of the gut microbiome. While much remains to be discovered, the future looks promising for those living with the condition.

References

1. What's really behind ‘gluten sensitivity'? Science. Available at: https://www.science.org/content/article/what-s-really-behind-gluten-sensitivity.
2. Olivares M, Flor-Duro A, Sanz Y. Manipulation of the gut microbiome in gluten-intolerance. Curr Opin Clin Nutr Metab Care. 2021;24(6):536-542.