Daily Fiber Targets and Exercise Calorie Burn, Explained
How recommended fiber intake and MET-based calorie burn estimates are calculated, with real examples.
Fiber targets and exercise calorie burn are both estimated using simple scaling formulas — one scales with your calorie intake, the other scales with your body weight and exercise intensity.
Fiber: scaled to calorie intake
A commonly cited guideline recommends about 14 grams of fiber per 1,000 calories consumed. At a 2,000 kcal daily intake: (2,000/1,000) × 14 = 28 grams of recommended daily fiber. This scaling approach (rather than a single fixed number for everyone) accounts for the fact that people eating more food overall generally need proportionally more fiber to maintain the same digestive benefit.
Exercise calorie burn: the MET formula
Calories = MET × 3.5 × weight(kg) / 200 × minutes. Running (MET value around 9.8) for 30 minutes at a 75kg body weight: 9.8 × 3.5 × 75 / 200 × 30 = 2,572.5/200 × 30 = 12.8625 × 30 ≈ 386 calories burned.
What a MET value actually represents
MET stands for Metabolic Equivalent of Task — 1 MET is defined as the energy cost of sitting quietly at rest. An activity with a MET of 9.8 (running) burns roughly 9.8 times the energy of resting quietly, for the same duration. Walking (MET ≈ 3.5) burns much less per minute than running, but far more than sitting still (MET = 1), which is exactly what the formula's linear MET scaling captures.
Why heavier individuals burn more calories for the same activity
Because weight appears directly in the calorie-burn formula, a heavier person burns more calories performing the identical activity at the identical duration and intensity than a lighter person — moving more mass requires proportionally more energy, all else being equal.
Common mistakes to avoid
- Using a single generic MET value for an activity that actually varies widely in intensity (like "running," which spans a huge pace range with correspondingly different true MET values)
- Assuming fiber and calorie needs scale identically for everyone — the fiber guideline is a population average, and individual digestive tolerance varies
- Treating calculated calorie burn as precise rather than a reasonable estimate — actual energy expenditure varies with fitness level, terrain, and individual efficiency
Calculate your own targets with the fiber intake calculator and calories burned calculator.