A 2026 digestion model, checked against a feeding study, estimated about 116 fewer calories absorbed per day on a higher-fiber pattern

What the research found

Study (mathematical model checked against an earlier feeding trial). Taylor Davis, Rosa Krajmalnik-Brown, Bruce Rittmann, and colleagues at Arizona State University describe a digestion, absorption, and microbial metabolism model in PLOS One (2026; DOI 10.1371/journal.pone.0347668). They compared it with a controlled feeding study of healthy adults. One pattern was high in fiber and resistant starch, with larger particle size. The other resembled a usual Western pattern, lower in fiber. People on the Western pattern absorbed about 116 more calories per day. The higher-fiber group did not report more hunger. The model estimated that short-chain fatty acids from the colon supplied about 140 calories a day, about 7.4 percent of usable energy, and that about 85 percent of usable energy came from the upper gut and about 15 percent from the lower gut. Standard label math underestimated absorbed calories. This is a research framework, not a personal meal plan. Not medical advice.

Evidence level: Human study. A study in people, but an association isn't proof of cause.

Read the original at Arizona State University / PLOS One