Iodinated oil (Ethiodol, 1 or 2 ml) was administered po or by im administration to adult women and older children in rural highland Ecuador who were either well nourished or malnourished to determine the effect of nutritional status on the disposal rate of iodine. These subjects resides in a region previously severely deficient in iodine, but this had been corrected in these subjects by prior administration of iodinated oil or by use of iodized salt or both. Malnutrition as determined by the conventional standards of height for age was associated with a significantly shortened retention time of the administered iodine, whether given po or im. The half life of retention was approximately half in the malourished of that in the well nourished. If these findings can be extrapolated to chronically iodine deficient subjects, then malnourished populations in need of iodine supplementation should either receive higher dosages than those conventionally employed or more frequent dosage.