A simple method to estimate neutral detergent fiber content of typical daily menus.

The purpose of this research was to develop a simple method to estimate daily intakes of the insoluble fraction of dietary fiber, that portion most effective in increasing stool weight and defecation frequency and decreasing gastrointestinal transit time. Neutral detergent fiber (NDF) contents of 53 foods were determined by analysis and used to calculate the NDF content of typical institutional menus; mean NDF content (n = 14 days) was 10.8 +/- 1.4 g/day. Average NDF content of one serving of fruits and vegetables was approximately 1 g, of the refined grain products, approximately 0.5 g. Estimating daily NDF content of the menus was simplified without a loss of accuracy by substituting the mean NDF content of one serving of refined grains, vegetables, and fruits for the actual values, and by eliminating foods present at less than 1/4 of a serving. Crude fiber was a poor predictor of the NDF in a menu.