Skim milk still has a lot of protein.

I consume a lot of milk but whole milk can be unpalatable so I mostly drink low-fat, which still has some fat and a lot of protein:

    There are 102 calories in 1 cup of 1% Fat Milk.
    Calorie breakdown: 21% fat, 47% carbs, 32% protein.

It also naturally contains calcium and vitamins B and D.

http://www.fatsecret.com/calories-nutrition/generic/milk-cow...