The quantity of zinc absorbed from wheat in adult women is enhanced by biofortification.
Biofortification of crops that provide major food staples to large, poor rural populations offers an appealing strategy for diminishing public health problems attributable to micronutrient deficiencies. The objective of this first-stage human study was to determine the increase in quantity of zinc (Zn) absorbed achieved by biofortifying wheat with Zn. Secondary objectives included evaluating the magnitude of the measured increases in Zn absorption as a function of dietary Zn and phytate. The biofortified and control wheats were extracted at high (95%) and moderate (80%) levels and Zn and phytate concentrations measured. Adult women with habitual diets high in phytate consumed 300 g of 95 or 80% extracted wheat as tortillas for 2 consecutive days using either biofortified (41 mg Zn/g) or control (24 mg Zn/g) wheat. All meals for the 2-d experiment were extrinsically labeled with Zn stable isotopes and fractional absorption of Zn determined by a dual isotope tracer ratio technique. Zn intake from the biofortified wheat diet was 5.7 mg/d (72%) higher at 95% extraction (P < 0.001) and 2.7 mg/d (68%) higher at 80% extraction compared with the corresponding control wheat (P = 0.007). Zn absorption from biofortified wheat meals was (mean +/- SD) 2.1 +/- 0.7 and 2.0 +/- 0.4 mg/d for 95 and 80% extraction, respectively, both of which were 0.5 mg/d higher than for the corresponding control wheat (P < 0.05). Results were consistent with those predicted by a trivariate model of Zn absorption as a function of dietary Zn and phytate. Potentially valuable increases in Zn absorption can be achieved from biofortification of wheat with Zn.
Rosado
Jorge L
JL
Universidad Autónoma de Querétaro, School of Natural Sciences, Querétaro, Mexico 76000.
Hambidge
K Michael
KM
Miller
Leland V
LV
Garcia
Olga P
OP
Westcott
Jamie
J
Gonzalez
Karla
K
Conde
Jennifer
J
Hotz
Christine
C
Pfeiffer
Wolfgang
W
Ortiz-Monasterio
Ivan
I
Krebs
Nancy F
NF
D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D005433:Flour / Q000032:analysis*; D005527:Food, Fortified / Q000032:analysis*; D006801:Humans; D008800:Mexico; D014908:Triticum / Q000737:chemistry*; D055815:Young Adult; D015032:Zinc / Q000737:chemistry* / Q000378:metabolism* / Q000652:urine; D015033:Zinc Isotopes
D015033:Zinc Isotopes; D015032:Zinc