Not generally. There has been concern that
- some dietary fiber contains phytate (inositol hexaphosphate) that may form insoluble compounds with vital minerals
- oxalates may interfere with the absorption of iron
But it is unlikely that a nutrient deficiency would occur from a high-fiber diet if an adequate, balanced diet is consumed. The human body adapts to the continued intake of relatively high amounts of dietary fiber. There is a period of compensated lasting 8-10 weeks after starting a high-fiber diet. The body also compensates for the decreased availability of phytate-bound minerals by increasing absorption.