Effectiveness of fortified flour for enhancement of vitamin and mineral intakes and nutrition status in northwest Chinese villages.

摘要

Background. Fortification of flour is one of the approaches for the control and prevention of vitamin and mineral deficiencies. Objective. To assess the effect of fortification of flour with seven vitamins and minerals on a population of Chinese women. Methods. Farmers who offered their land for reforestation in 25 northwest provinces of China received compensation in the form of wheat flour; the amount of flour given depended on the amount of land that was given up for reforestation. This study observed the effects of providing families with fortified flour in the reforestation areas in Gansu Province. The study was conducted for 3 years. Families in the intervention village who offered land for reforestation received flour fortified with seven vitamins and minerals, and those in the control village received unfortified flour. Seven surveys, spaced at least 6 months apart, were carried out in each village from 2004 to 2007. At baseline and at each annual survey, measurements and blood samples were taken from 300 adult female subjects aged 20 to 60 years to assess dietary intake, height, weight, body fat, hemoglobin, serum retinol, serum iron, free erythrocyte protoporphyrin, serum zinc. Serum folic acid was measured at baseline and 36-month only. At each 6-month survey, data were collected on anthropometric features, hemoglobin, and dietary intake. Results. Consumption of fortified flour in the intervention village ranged from 158.7 to 232.7 g per person per day. Serum retinol status was significantly improved after 12-month intervention until the end of the trial compared with both the control group and the baseline level of the intervention group. Iron status expressed as FEP and SI levels showed higher than that of the control group and baseline levels only at 36-month. Hemoglobin levels of the intervention group were higher than that of the control group and baseline levels, but anemia prevalence of both the intervention and control groups remained unchanged in the intervention period. Levels of serum zinc showed increases compared with the control group and baseline data at 24-month and 36-month, and levels of serum folic acid of intervention group in 36-month was higher than that of both the control group and baseline level. Conclusions. The evidence from this study confirms the positive bioeffectiveness of fortified flour in the rural female population in China, but a higher dosage of electrolytic elementary iron in flour fortification was suggested for anemia prevention and control.