One serving against a day's fiber
The Dietary Reference Intakes set an Adequate Intake for total fiber of 25 g a day for women aged 19 to 50 and 38 g for men of the same ages. Measured against those, the 25.7 g in a 1 cup serving of wheat bran is 103% of the first and 68% of the second. US food labels use a single Daily Value of 28 g instead, which puts this serving at 92%.
Calorie for calorie, the figure is 19.8 g of fiber per 100 kcal (this serving is 130 kcal). Among the 186 grains with USDA energy data here that is 1st, and 1st across all 957. The intakes above were derived from 14 g of fiber per 1,000 kcal, or 1.4 g per 100 kcal, so this food sits above the ratio a whole day of eating is meant to reach.
Getting all 25 g from wheat bran alone would take 1 servings, and 38 g would take 2. Most days reach the target through several different sources.
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