Background: Iodine is necessary for the production of thyroid hormones and is acquired through the diet. Cow's milk is a primary source of iodine in the U.S. diet. The objective of this study was to measure the iodine content in a variety of milk alternatives to determine whether milk alternatives contain iodine levels comparable to that of cow's milk.
Methods: Iodine levels from 30 different brands of milk alternatives from 16 different companies were measured by the spectrophotometric method of the Sandell-Kolthoff reaction.
Results: The 30 brands of milk alternatives contained an average of 3.1 ± 2.5 μg/250 mL (∼8 oz. or one cup, serving size) of iodine or 12.3 ± 10.1 μg/L (∼24 oz. or four cups, daily recommended serving for adequate calcium intake) of iodine.
Conclusions: These results indicate that milk alternatives contain far less iodine than cow's milk. Individuals with restricted dairy product consumption are at risk for inadequate dietary iodine intake.