This double blind, randomized control trial in India demonstrated that double-fortified salt is an efficacious approach to improving iron status and should be further evaluated for effectiveness in the general population.
Jere D. Haas, J.D., Rahn, M., Venkatramanan, S. et al. The Journal of Nutrition. (April 2014) Vol. 144 No. 6, pp. 957-964.