Trial of Thiamine Supplementation in Cambodia

Beriberi is a potentially fatal disease caused by vitamin B1 (thiamine) deficiency that still occurs in Southeast Asia despite near eradication elsewhere. Mothers with a diet low in thiamine produce thiamine-poor milk, putting their infants at a high risk of developing thiamine deficiency and beriberi. There is also a growing body of evidence suggesting thiamine deficiency not severe enough to cause clinical symptoms may negatively effect cognitive development and functioning of the infant. Since human milk should be the sole source of nutrition for babies during the first six months, maternal thiamine intake must be improved to combat this disease. The investigators' recent study of thiamine-fortified fish sauce in Cambodia showed that fortification could increase maternal and infant thiamine status'. However, centrally produced fish sauce may not reach the poorest communities who make their own fish sauce, and fish sauce is not consumed in all regions where we find thiamine deficiency. Salt, by contrast, is a common condiment in most regions of the world and has proven to be a successful global fortification vehicle for iodine. Suboptimal maternal thiamine intake puts exclusively breastfed infants at risk of low thiamine status, impaired cognitive development, and infantile beriberi, which can be fatal. Thiamine fortification of salt is a potentially low-cost and sustainable means of combating suboptimal thiamine status; however knowledge gaps must be filled before thiamine fortification can proceed. In this study, mothers will consume thiamine supplements in order to model the thiamine dose required to optimize human milk thiamine concentrations for the prevention of beriberi. Other thiamine biomarkers will be assessed, and usual salt intake will be measured. Finally, the investigators will assess the effects of early-life thiamine exposure on infant neuro-cognitive development.