Researchers at Arizona State University have developed a new mathematical model to track exactly how food energy moves through the human body. The Digestion, Absorption, and Microbial Metabolism framework, known as DAMM, calculates energy intake by looking at both human digestion and the work performed by gut bacteria.
The research team found that digestion is a collaborative process between our bodies and our microbiome. While the small intestine absorbs the bulk of energy, the colon ferments remaining residues. This microbial process is critical for understanding the true caloric value of food.
In a clinical trial, subjects on a low-fiber Western diet absorbed 116 more calories daily than those on a fiber-rich diet, despite reporting the same levels of satiety. Fiber-rich diets encourage the production of short-chain fatty acids through fermentation, which changes the total energy balance without increasing net absorption.
This new framework outperforms traditional calorie counting methods by accounting for the high variability in human microflora. Because every person has a unique set of gut bacteria, a one-size-fits-all approach to nutrition often misses the mark.
Scientists expect this tool to influence the treatment of metabolic conditions such as obesity and diabetes. By predicting how specific individuals process different foods, clinicians will eventually create personalized nutrition plans that align with the metabolic reality of the gut microbiome.