What is the difference between protein milk and protein supplements?

Generally, ‘protein milk’ contains additional milk protein (composed of approximately 80 % casein and 20 % whey) and this increases the protein content from approximately 3.5 % in regular milk to 5 % in protein milk. Apart from this, ‘protein milk’ reflects a similar nutrient profile to regular milk, unless other additional ingredients are added such as flavours (these will be stated in the ingredients list).

Protein supplements, which usually are in powdered form, can be varied with many varieties on the market. Those providing milk protein may be either casein or whey isolate which provide only the specified protein constituent; alternatively casein or whey concentrate may include additional ingredients.