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 8 g in a 1 cup serving of raspberries is 32% of the first and 21% of the second. US food labels use a single Daily Value of 28 g instead, which puts this serving at 29%.
Calorie for calorie, the figure is 12.5 g of fiber per 100 kcal (this serving is 64 kcal). Among the 121 fruits with USDA energy data here that is 2nd, and 11th 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 raspberries alone would take 4 servings, and 38 g would take 5. Most days reach the target through several different sources.
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