The bacteria which populate our digestive systems may play a key role in weight management. There is evidence that the composition of your gut bacteria and your size are tied. A study on mice showed that obese mice had a significantly different set of bacteria in their gastrointestinal tract than lean mice. The study then swapped bacteria between obese mice and lean mice and saw that the lean mice started to put on weight, even though they were eating the same thing.
Further research shows that certain methane-producing bacteria slows down the transit of food through the gut. This led to the idea that as food moves slower through your gut, your body has more time to extract nutrients. This makes a lot of sense, because we know that sluggish bowel movements means that the colon extracts too much water (making stools hard and dry), so it stands to reason to say that the rest of the gut has more time to extract calories.
constipation can be a sign of an imbalance in gut flora and topping up your levels of friendly bacteria (probiotics) has a positive effect on the breakdown of food and absorption of nutrients. They also aid in the production of substances in the bowel which are required for healthy bowel function. Probiotics can also reduce feelings of bloating and heaviness in the digestive system as well, which can give you a lighter feeling and reduce the appearance of stomach bloating