Scientists are learning that feeding the trillions of microbes living in our gut may be more important than simply adding a probiotic pill.
A new study led by King’s College London and ZOE suggests that eating a much wider variety of plant foods every day can improve the balance of gut bacteria far more effectively than a common probiotic supplement. The research was published in the British Journal of Nutrition.
Inside the human digestive system live billions of bacteria, fungi, and other tiny organisms that together form the gut microbiome. These microbes help digest food, make vitamins, support the immune system, and may even influence mood and energy. When the microbiome becomes less healthy, digestive problems and other health issues may become more common.
For many years, probiotic supplements have been promoted as an easy way to improve gut health. However, scientists are increasingly finding that the bacteria already living in the gut also need the right food to grow. Different plants provide different types of fiber and natural compounds that nourish different kinds of beneficial microbes.
The researchers recruited 349 adults in the United Kingdom for a randomized controlled trial. One group consumed a 30-gram Daily30 plant blend each day containing more than 30 vegetables, fruits, nuts, seeds, herbs, spices and mushrooms.
Another group received bread croutons with similar calories, while a third group took a probiotic capsule containing Lactobacillus rhamnosus.
After six weeks, the differences were striking. People eating the plant blend showed increases in 57 beneficial bacterial species, while the probiotic group showed changes in only four species and the control group changed in 14 species.
The bacteria that increased in the plant group were generally linked with better health, while bacteria linked with poorer health became less common.
Participants also noticed practical benefits in daily life. Many reported having more energy, feeling happier, suffering less indigestion, constipation, heartburn and gas, and feeling less hungry. In a smaller meal study, people who ate a carbohydrate-rich meal together with the plant blend felt fuller, more satisfied and less interested in eating afterwards.
Professor Sarah Berry said the findings suggest that feeding existing gut microbes with many different plant foods may be much more powerful than relying on a single bacterial strain in a capsule. Professor Tim Spector added that strong scientific evidence should guide nutrition choices instead of marketing claims.
This study has several strengths because it was a randomized controlled trial involving hundreds of participants. However, the research lasted only six weeks, so scientists still need longer studies to learn whether the benefits continue over many months or years.
The supplement tested was also a specially designed product, so future research should examine whether similar results can be achieved using ordinary whole foods alone.
Overall, the findings support growing evidence that variety matters as much as quantity when eating plant foods. Instead of searching for one miracle supplement, people may benefit more from regularly eating many different fruits, vegetables, beans, whole grains, nuts, seeds, herbs and spices.
This study provides strong evidence that plant diversity can improve the gut microbiome more effectively than a single-strain probiotic over the short term. Although the results are encouraging, they do not mean probiotics have no value or that everyone needs the tested supplement.
Longer clinical studies are needed, but the research strengthens the idea that a diverse plant-rich diet is one of the best foundations for good gut health.
For more information about gut health, please see recent studies about the crucial link between diet, gut health, and the immune system and results showing that Low-gluten, high-fiber diets boost gut health and weight loss.
For more information about gut health, please see recent studies about Navigating inflammatory bowel disease (IBD) with diet and results showing that Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
Source: King’s College London.
