Within your digestive system are billions of microorganisms. These viruses, bacteria, and fungi collectively are known as the gut microbiome. According to MedlinePlus, the microbiome is all of the tiny organisms (bacteria, fungi, and others) that normally live on and in our bodies. Research on the microbiome and weight is still new. Scientists have found links between gut bacteria and body weight, but they have not shown that changing gut bacteria alone causes weight loss. Weight is affected by many things, including diet, physical activity, age, sleep, and genes.
What is a Gut Microbe?
Microorganisms are found on your skin as well as inside your body. There are many kinds of bacteria that reside in your digestive tract. While some could cause illness, the majority perform essential functions to help you stay healthy. These microbes help the body digest food, make some vitamins, and support the immune system.
What Science Says About the Gut Microbiome
According to MedlinePlus, the microbiome is all of the tiny organisms (bacteria, fungi, and others) that normally live on and in our bodies. The gut microbiome is the community of these microorganisms that live in the digestive tract. These microbes help digest food, make some vitamins, and support the immune system. Research on the microbiome and weight is still new. Scientists have found links between gut bacteria and body weight, but they have not shown that changing gut bacteria alone causes weight loss. Weight is affected by many things, including diet, physical activity, age, sleep, and genes.
Foods That Support a Healthy Gut
According to the NHS, a healthy gut needs a varied diet with plenty of fibre. Government guidelines say that dietary fibre intake should increase to 30 grams a day, as part of a healthy balanced diet. Most adults in the UK are only eating about 20 grams of fibre a day. Foods that help include fruits, vegetables, beans, lentils, oats, and whole grains.
Probiotics: What They Are and What They Cannot Do
Probiotics are live microbes found in some foods and supplements. According to the Mayo Clinic, probiotics may help the body digest food or help with symptoms of certain illnesses. Researchers continue to look for a link between gut microorganisms and health conditions. Research has shown promise, but it has not yet proved that probiotics help with a specific health condition. The U.S. Food and Drug Administration does not regulate probiotic supplements, so check with your healthcare professional before taking them. A supplement is not a replacement for a healthy diet.
Weight Management: The Basics That Work
According to the Centers for Disease Control and Prevention (CDC), adults should aim for at least 150 minutes of moderate physical activity each week, such as brisk walking. The CDC also advises a healthy eating pattern with plenty of vegetables, fruits, whole grains, and lean protein, and less added sugar, salt, and saturated fat. Small, steady changes work better than quick diets. A doctor or a dietitian can help a person set a safe weight goal.
Frequently Asked Questions
What is the gut microbiome?
According to MedlinePlus, the microbiome is all of the tiny organisms (bacteria, fungi, and others) that normally live on and in our bodies. The gut microbiome is the community of these microorganisms that live in the digestive tract. These microbes help digest food, make some vitamins, and support the immune system.
Can gut bacteria affect my weight?
Research has found links between gut bacteria and body weight, but scientists have not shown that changing gut bacteria alone causes weight loss. Diet, activity, sleep, age, and genes also affect weight.
Which foods help gut health?
According to the NHS, a varied diet with plenty of fibre helps the gut. Adults are advised to eat about 30 grams of fibre a day from fruits, vegetables, beans, lentils, oats, and whole grains.
Do probiotics help with weight loss?
No. According to the Mayo Clinic, researchers continue to look for a link between gut microorganisms and health conditions, and research has shown promise but has not yet proved that probiotics help with a specific health condition. Check with your healthcare professional before taking probiotic supplements.
How much physical activity do adults need?
According to the CDC, adults should aim for at least 150 minutes of moderate physical activity each week, plus muscle-strengthening activities on two or more days a week.
Disclaimer: This guide is for general information only. It is not medical advice and it does not replace care from a doctor. This guide gives no medical advice for readers. Talk to a doctor or a dietitian before you change your diet or start a supplement.
Last Updated: 6 November 2026