Gut and Digestion

Digestive symptoms are not random

Researchers have found a strong, well-tested link between gut bacteria and digestion. More than 4 in 10 people worldwide have a digestive disorder like irritable bowel syndrome, ongoing constipation, or bloating, based on a study of 73,076 adults across 33 countries. These symptoms often get blamed on bad luck or a sensitive stomach, but something this common usually has one cause behind it: the community of bacteria living in your gut, called the gut microbiome.

Source: Rome Foundation, Worldwide Prevalence and Burden of Functional Gastrointestinal Disorders

Your gut bacteria are the real cause

The gut microbiome breaks down fibre and food compounds the body cannot fully digest on its own. In doing so, it produces short-chain fatty acids, compounds that protect the gut lining, calm the immune system, and help control energy use. One of these short-chain fatty acids is called butyrate, and researchers have tested it directly. In a clinical trial, 51 children with IBS were split into two groups: half took butyrate, half took a placebo. The results were clear: 73% of the children on butyrate got better, compared with only 3.8% on placebo.

Source: The BMJ, Role of the gut microbiota in nutrition and health

Source: Journal of Pediatric Gastroenterology and Nutrition, Calcium butyrate efficacy in pediatric irritable bowel syndrome

Diet controls this, and it works fast

That trial used butyrate on its own, as a supplement. Most people get it through food instead, so the real question is whether ordinary eating habits can change how much of it your gut makes. The American Gut Project analysed samples from more than 10,000 people and found that plant diversity, not diet labels like "vegan" or "omnivore", was what tracked with gut bacteria. People eating more than 30 different plant types per week carried noticeably more of the bacteria that make short-chain fatty acids than those eating 10 or fewer.

The last thing worth knowing is how fast this can happen. In a Stanford clinical trial, 36 healthy adults followed either a 10-week fermented-food diet or a high-fibre diet. The fermented-food group ended up with more diverse gut bacteria and lower levels of 19 inflammatory proteins in their blood, including interleukin-6. The high-fibre group did not see the same drop. Two diets that both sound healthy produced different, measurable results within ten weeks. Put simply: your gut bacteria make the compounds that ease digestive symptoms, food decides which bacteria you have, and that can shift within weeks, not years.

Source: American Gut Project, American Gut: an Open Platform for Citizen Science Microbiome Research

Source: Stanford Medicine, Fermented-food diet increases microbiome diversity, decreases inflammatory proteins

What this means for you

If you notice bleeding, unexplained weight loss, or ongoing pain, get it checked by a doctor. For everyday digestive discomfort, the research above gives you something concrete to act on: eat a wider variety of plant foods, and build up fibre and fermented foods gradually. That's the same idea behind GutLab, everyday gut health starts with regularly feeding the microbiome a broad range of plant-rich ingredients.

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