yes, skim milk has protein in it, but not to the degree that an isolated protein shake
would. therefore, you would need to drink A LOT of skim milk to equal the protein
and/or calories in a regular portion of a calorie-dense protein shake. for specific weight gain, you don't want to be drinking skim milk either, as it's much lower in fat (and therefore calories) than a higher fat milk like 2% or whole.