Studies on the consumption of 'fibre-filler' for twelve weeks in humans: effects on iron status and plasma zinc

Forty adult subjects (14 male, 14 female omnivores; five male, seven female vegetarians) were given a daily fibre supplement of cereals, fruits and nuts ('fibre-filler', F-plan diet, Eyton, 1982) incorporated into their normal diet for twelve weeks. Various haematological parameters were monitored from fasting blood samples taken at regular intervals throughout the study.
Two-way analysis of variance of the data from the initial blood samples showed that habitual diet had no effect on any of the measured variables, but that there was a significant difference between men and women for all but % transferrin saturation. Mean Hb levels gradually increased during the course of the study, and there were fluctuations in plasma zinc. No other parameters changed with time.
It was concluded that the fibre supplement under investigation, which contributed an additional 12 mg iron and 2.6 mg zinc to the daily intake, had no adverse effect on iron or zinc status when consumed by subjects as part of their normal diet.