There was a very useful information from one of the members of Facebooks Tokyo Mother Group so I'd like to share. I've been writing about how to read labels on milk cartons in my Tokyo Grocery Shopping Guide Page, but there seems to be a simpler solution to this.
It is the indentation you see on top of the milk carton. This is made so the visually impaired person can tell whether they are getting whole milk instead of other dairy drinks. Although this is not compulsory, it seems that most manufacturers have implemented this rule (I've check out my local supermarket). I find it quite useful not only for blind people but also for foreigners that cannot read kanji characters. So next time you are shopping for whole milk, look for the indentation!
Details of this can be found in my Tokyo Grocery Guide Milk page.
I'm Miyuki and I teach Japanese Home cooking at my home in Tokyo.