I have read online that cow's milk is a good source of Magnesium.
Example: http://abcnews.go.com/Health/13-foods-high-magnesium/story?id=30567212
However, the nutrition labels for various brands that I buy seem to never list Magnesium on the nutrition facts label.
Example: http://www.prairiefarmsdairy.com/index.php?p=453&i=693
Is the magnesium somehow lost in processing, or is the nutrition label simply incomplete, or what other reasons could explain the difference?