Research finds lower iodine concentration in organic milk

A study by the University of Reading, published in the journal Food Chemistry, has found that winter organic milk UHT milk has an iodine concentration that is up to 35% lower than winter conventional milk. They also found that UHT milk was lower (around 30%) than conventional milk. This study supports the findings of the 2012 study by group members Dr Bath and Professor Rayman, who found organic milk had a 42% lower iodine concentration than conventional milk in summer samples.

The study received widespread media coverage, as the headlines linked the finding to risk of low IQ in offspring of pregnant women who consume organic milk, even though the study had no measures of iodine status, or cognitive function. Group members Professor Rayman and Dr Bath provided expert comments to the Science Media Centre. The comments by Dr Bath were picked up by the Daily Mail, Telegraph and the Guardian newspapers.