New research has suggested that organic milk could be ‘less healthy’ than conventionally produced milk.

The research, from the University of Reading, showed that certified organic milk contains up to a third less iodine than conventional milk. UHT milk also had a reduced amount of iodine. There was no difference between full-fat, semi- and skimmed-milk.

Commenting on the findings this week, study author Prof Ian Givens acknowedged that there are numerous different health benefits from drinking all types of milk. However, he did add that, unless due attention is paid to iodine deficiency, we risk “Sleepwalking into a new health crisis in the 21st century.”

On Tuesday, organic farmers reacted angrily to the findings. Helen Browning, chief executive at the Soil Association, cdownplayed the response to the study as “Pure scaremongering.”

Iodine plays a part in brain development in babies, and is especially important during the early stages of pregnancy. Though the study’s authors said milk is the main source of iodine in most UK diets, Helen Browning called the researchers’ conclusions “irresponsible” and pointed out that the NHS does not cite milk in its list of good sources of iodine.

Even so, the findings could be a blow for the organic sector, which has recently returned to growth, with yoghurt and dairy products leading sales of organic produce.
 
The Soil Association Chief Executive said that organic milk is the most thoroughly researched organic food, and discussed other health benefits, claiming that organic milk has been shown to contain more beneficial omega-3 fatty acid, Vitamin E and beta-carotene.
  
Browning said, “There are variations of levels of iodine in milk which are unrelated to whether or not it is organic. According to The Dairy Council there are seasonal variations - winter milk, may contain slightly higher levels of iodine than summer milk.”

Even so, she added, “The Soil Association is aware of potentially lower levels of iodine in organic milk and we are working with farmers and scientists to find ways of addressing this issue whilst keeping all the other benefits consumers rightly expect.”