A huge public outcry about the ‘hidden’ permeate in milk has recently led many companies to declare their product ‘permeate-free’.

But according to many nutritionists, this really has been much ado about nothing. Permeate is simply a watery by-product of milk processing,  which some manufacturers add back to milk to enhance consistency.

“As the composition of milk can change in hot and cold months and due to where cows are in their lactation cycle, milk companies aim to keep their products consistent in the level of fat and protein by separating the streams and recombine them,” Catherine Saxelby explains.

“But there are no actual proven health problems due to permeate in milk.”

Catherine Saxelby is a nutritionist and author of Complete Food and Nutrition Companion (Random House, $45) and founder of the website Foodwatch.

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