How Gut Bacteria May Affect the Calories Your Body Uses

Scientists are learning that the human gut does much more than simply digest food. Inside the digestive system live trillions of tiny microbes, mainly bacteria, that help break down food and support many body functions. A new research study looked at how these gut microbes may affect the way the body gets and uses energy from food.

The researchers created something called the Digestion, Absorption, and Microbial Metabolism (DAMM) model. This computer model was designed to better understand what happens to food after people eat it. Instead of only looking at calories from food labels, the model also studied how gut bacteria may change the amount of energy the body actually receives.

Normally, food labels estimate calories based on the nutrients in foods like carbohydrates, fats, and proteins. But the researchers explained that this may not tell the full story. Some food is broken down by gut microbes before the body absorbs it. During this process, gut bacteria create substances called short-chain fatty acids. These substances can also provide energy to the body.

The study found that gut microbes may play a bigger role in energy balance than many people realize. Different foods may feed gut bacteria in different ways. Foods rich in fiber, for example, can be used by certain microbes in the colon. While humans cannot fully digest fiber on their own, gut bacteria can break some of it down and create helpful compounds during fermentation.

The DAMM model also showed that not every person may get the exact same amount of energy from the same meal. Since people have different gut microbiomes, their bodies may process foods differently. This could help explain why nutrition and digestion can vary from person to person.

Researchers believe this type of model may help scientists better understand digestion, metabolism, and personalized nutrition in the future. It may also improve the way experts estimate how much energy foods truly provide to the body.

Even though more research is still needed, the study highlights how important gut health may be for overall wellness. Eating a balanced diet with fiber-rich foods like fruits, vegetables, beans, and whole grains may help support a healthy gut microbiome.

This research reminds us that digestion is not only about the stomach or intestines. Tiny microbes inside the gut may also play an important role in how the body uses food for energy every day.