Low-phytate wholegrain bread instead of high-phytate wholegrain bread in a total diet context did not improve iron status of healthy Swedish females: a 12-week, randomized, parallel-design intervention study
Journal article, 2019

Purpose To investigate the effects of eating wholegrain rye bread with high or low amounts of phytate on iron status in

women under free-living conditions.

Methods In this 12-week, randomized, parallel-design intervention study, 102 females were allocated into two groups, a

high-phytate-bread group or a low-phytate-bread group. These two groups were administered: 200 g of blanched wholegrain

rye bread/day, or 200 g dephytinized wholegrain rye bread/day. The bread was administered in addition to their habitual daily

diet. Iron status biomarkers and plasma alkylresorcinols were analyzed at baseline and post-intervention.

Results Fifty-five females completed the study. In the high-phytate-bread group (n = 31) there was no change in any of the

iron status biomarkers after 12 weeks of intervention (p > 0.05). In the low-phytate bread group (n = 24) there were significant

decreases in both ferritin (mean = 12%; from 32 ± 7 to 27 ± 6 μg/L, geometric mean ± SEM, p < 0.018) and total body iron

(mean = 12%; from 6.9 ± 1.4 to 5.4 ± 1.1 mg/kg, p < 0.035). Plasma alkylresorcinols indicated that most subjects complied

with the intervention.

Conclusions In Swedish females of reproductive age, 12 weeks of high-phytate wholegrain bread consumption had no effect

on iron status. However, consumption of low-phytate wholegrain bread for 12 weeks resulted in a reduction of markers of

iron status. Although single-meal studies clearly show an increase in iron bioavailability from dephytinization of cereals,

medium-term consumption of reduced phytate bread under free-living conditions suggests that this strategy does not work

to improve iron status in healthy women of reproductive age.

Non-heme iron · Iron status · Phytate · Wholegrain · Dietary intervention · Women


Michael Hoppe

Sahlgrenska University Hospital

University of Gothenburg

Alastair Ross

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Cecilia Svelander

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Ann-Sofie Sandberg

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Lena Hulthén

University of Gothenburg

European Journal of Nutrition

1436-6207 (ISSN) 1436-6215 (eISSN)

Vol. 58 2 853-864

Subject Categories


Food Science

Nutrition and Dietetics

Areas of Advance

Life Science Engineering (2010-2018)



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