The trillions of microbes inside of our gut play many very important roles in our body. Not only does this “microbiome” regulate our metabolism and help us absorb nutrients from food into the body, it can also influence whether we are lean or obese.
Recent research even suggests that our gut microbiome can influence our ability to lose weight. Researchers from the University of Washington in the US found that the presence of specific “good” microbes in the gut of people dieting to lose weight affected how many pounds they were able to lose.
To understand what effect a person’s gut microbes have on weight loss, the researchers looked at 105 overweight people, all of whom were enrolled in a year-long weight loss programme. To track their weight loss, the researchers recorded participants’ starting body mass index (BMI).
The scientists also recorded the levels of certain blood markers of metabolism – such as cholesterol levels – to understand how easily each participant could burn fat. And stool samples were collected at the beginning and end of the study to determine which microbes were present in each participant’s gut – and at which levels.
The researchers then compared people who had lost weight (at least 1% of their bodyweight on average each month) to those whose weight had remained the same. They discovered that various blood markers related to metabolism were only minimally different between those who did and didn’t lose weight.
But really different were the types of gut microbes that the two groups had. In people who lost more weight, they had more beneficial bacterial enzymes in the gut. These enzymes helped to break down complex carbohydrates (like those found in whole grains) into simple sugars, which makes them easier to digest and potentially less likely to store them as fat.