Zinc deficiency is affecting millions of people in South East Asia. This analysis quantified the impact of rice zinc biofortification on the prevalence of inadequate zinc intakes among adult women in Bangladesh, the Philippines, and Indonesia.
We used nationally representative dietary intake data from the Philippines (n=4242) and Indonesia (n=65678) and from two districts in Bangladesh (n=237). We simulated levels of rice zinc content starting from 24 ppm (2.4 mg/100g) to 100 ppm (10mg/100g) and substitution levels of conventional rice with biofortified rice varying from 10% to 70%. Losses of zinc during processing and cooking were taken into account. Usual intakes were computed using PC-Side and prevalence of inadequacy was determined using the EAR cut point methodology.
Mean usual rice intake (grams of raw grains) was the highest in Bangladesh at 419g/day (SD 8.4) and lowest in Indonesia at 163g/day (SD 0.4). In all 3 countries, baseline zinc inadequacy was higher than 90%. At 28 ppm and 40% substitution, prevalence of zinc inadequacy decreased by 15 percentage points (pp) in the Philippines (from 93% to 78%), 16 pp in Bangladesh (96% to 80%), whereas no significant change was observed in Indonesia. At 45 ppm and 40% substitution, there was a reduction of 10 percentage points in Indonesia with 28pp and 40pp reduction in the Philippines and Bangladesh respectively.
Biofortification of rice with zinc at 28 ppm and higher is effective in reducing the prevalence of zinc inadequacy among adult women eating rice as their main staple.