Inside the body, food is not processed solely by our own organs. It also interacts with microorganisms in the gut, which can influence how much energy the body ultimately absorbs.
Researchers have therefore developed a model called DAMM.
It tracks food through the digestive system and calculates what the body absorbs, what reaches the colon, and what gut bacteria do with the remainder.
Two types of diet
The study, published in PLOS ONE and reported by SciTechDaily, was based on a controlled trial involving healthy adults.
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Participants were given either a high-fiber diet with less processed food or a more Western-style diet containing a greater proportion of processed foods.
The model showed that gut bacteria can produce short-chain fatty acids, which the body can also use as a source of energy.
According to the researchers, these compounds contributed an average of about 140 calories per day.
Fewer calories
Participants following the Western-style diet absorbed approximately 116 more calories per day than those on the high-fiber diet.
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This occurred even though the high-fiber diet led to greater activity among gut bacteria.
The findings suggest that the gut may play an important role in determining how many calories the body actually obtains from food.
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