BACKGROUND High phytate (HP) consumption is a concern in developing countries because of the high prevalence of iron deficiency in these countries. OBJECTIVE We investigated whether habitual consumption of an HP diet reduces the inhibitory effect of phytate on nonheme-iron absorption. METHODS Thirty-two nonanemic females, 18-35 y of age, with normal body mass index but with suboptimal iron stores (serum ferritin, ≤30 μg/L), were matched for serum ferritin concentration and randomly assigned to HP and low-phytate (LP) groups, in a parallel design study. Each subject consumed HP or LP foods with at least 2 of their daily meals for 8 wk, resulting in a change in phytate intake (from 718 to 1190 mg/d in the HP group and 623 to 385 mg/d in the LP group). The serum iron response over 4 h after a test meal containing 350 mg of phytate was measured at baseline and postintervention. Ferritin, transferrin receptor, and hepcidin concentrations were measured at baseline and 8 wk. RESULTS Twenty-eight subjects completed the study (n = 14 per group). The serum iron response to the test meal increased in the HP group at postintervention, resulting in a 41% increase in the area under the curve (AUC; P < 0.0001). However, no effect was observed in the LP group (21% decrease in AUC; P = 0.76). The postintervention serum iron response was lower (P < 0.0001) in the LP group than in the HP group after controlling for the baseline serum iron response and hepcidin concentration, reflecting in a 64% lower AUC. CONCLUSIONS We found that habitual consumption of an HP diet can reduce the negative effect of phytate on nonheme-iron absorption among young women with suboptimal iron stores. Future studies are needed to explore possible mechanisms. This trial was registered at clinicaltrials.gov as NCT02370940.

BACKGROUND Maternal smoking has been known to have a negative impact on the well being of the developing fetus. Prenatal smoking has been associated with premature births, low birth weight and with certain birth defects. Small research studies have also found a negative correlation between maternal smoking and neonatal body iron. OBJECTIVES To study and compare the relationship between maternal and infants' body iron in smokers and non-smokers in a large matched-pair cohort. METHODS This was a prospective cohort study involving 144 mothers - 72 smokers and 72 non-smokers and their respective infants. Samples were obtained from maternal and infants' cord blood at delivery for Serum transferrin receptor (sTfR) and ferritin levels. Serum TfR and ferritin were measured by RAMCO ELISA and RIA assays. Total Body Iron (TBI) was calculated using the sTfR/ferritin ratio in a previously described formula by Cook et al. RESULTS Women who smoked had lower sTfR, higher ferritin and higher body iron compared to nonsmoking women. In contrast to their respective mothers, we found a small, but statistically significant negative correlation between smoking and infants' total body iron. The number of packs per day smoked was also negatively correlated with infants' ferritin and total body iron. Lower birth weight was noted in babies of smokers compared to nonsmokers (mean /- SD =3270 +/-475 vs. 3393 g +/- 475 g, p=0.03). CONCLUSION Women who smoked during pregnancy had higher iron stores but their newborn infants had lower iron stores than those of non-smoking mothers. The more packs per day (PPD) and more days smoked during pregnancy led to lower total body iron of the babies. There may be a negative dose-dependent response between fetal smoke exposure and infant iron stores.

To explore relationships between iron status and lymphocyte SHMT activity (ACT) and abundance (ABN), 118 postmenopausal women (54.3 y) enrolled in SIRBL (Soy Isoflavones for Reducing Bone Loss) study and 105 young women (21.2 y) were studied. Serum ferritin, folate, and vitamin B‐12, plasma total homocysteine (tHcy) and pyridoxal phosphate (PLP), lymphocyte SHMT ACT and ABN were determined. Subjects in the first (4.8 ng/mL; 93% premenopausal) and fifth (92.6 ng/mL; 98% postmenopausal) quintiles of serum ferritin were compared. The fifth quintile had higher median BMI (25 vs 22 kg/m 2 ; p <0.02), plasma PLP ( p <0.0001), total homocysteine ( p <0.05), and SHMT ABN ( p <0.0001), but significantly lower SHMT ACT ( p <0.02) than first quintile. Ferritin quintile Folate ng/mL B‐12 pg/mL PLP nmol/L tHcy nmol/L SHMT ACT cpm/ug protein SHMT ABN relative density First ( n ) 14.2 (45) 597 (45) 61.7 (45) 6.4 (45) 43.6 (27) 1.1 (21) Fifth ( n ) 13.1 (45) 521 (45) 93.9 (45) 6.6 (45) 13.0 (14) 12.3 (31) Increased iron status may enhance SHMT expression, favoring thymidine synthesis over Hcy remethylation, thus warranting further investigation. Funded by USDA Special Grant, NWRC, Iowa State University.