Cows are ruminants, and continuous grazers. Ruminants are mammals that are able to get nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion. Cows have a four compartment stomach and scientist define them by saying they have a miraculous gut.
On average, high quality milk is 27 percent protein, 37 percent lactose (milk sugar), and 30 percent fat. The remaining 6 percent is calcium, and other minerals.
The high percentage of lactose has given some people digestive issues for a long time. Up to 30 percent of adults have varying degrees of allergic responses to lactose. This is because lactase, its digesting enzyme in the gut, declines during childhood.
There at least 14 different proteins in milk split into two groups called casein proteins and whey proteins.
Casein represents about 80 percent of milk protein. Casein has poor results in producing lean mass in athletes, and in hospital studies of muscle loss. But it definitely has its use in some cases.
Whey represents about 20 percent of milk protein. Whey has superior results to any other protein, including eggs, meats, fish, soy, nut, pea, rice, and other plant proteins, in producing lean mass in athletes, and muscle in hospital studies. That is not to say that you should only consume whey protein if you want to gain lean muscle.
To legally call a product whey protein concentrate there has to be a lot of things at play. I won't bore you with the statistics but you will see a lot of cheap whey for sale in bulk stores and discount markets. If the individual selling the product does not say that the content of their product is between 30-90% whey protein then leave it on the shelf. The protein content should be on the label. Just because it says ‘Whey Protein Concentrate’ doesn’t mean it is something you should be consuming. They could be using low grade protein and that could be giving you the digestive issues. Near the top end of the whey scale (70 to 89 percent protein), only 10 to 25 percent of the mix is fat and lactose. That’s where you want your whey to be.
Whey protein concentrate can be further extracted to become whey protein isolate. The higher price of whey isolate can be money wasted in some cases as well. High end concentrates and isolates are fast proteins. This means they absorb fast when compared to meat or other sources of protein. Isolates can contain less lactose but the variance is pretty small. Isolates and hydrolysates go through a heavier refining process which can benefit those who need more protein in their regimen but have a hard time digesting it.
Half the dry weight of your body is protein. The quality of your proteins determines both the quality and the quantity your individual DNA. Quality of the proteins in milk depends on the nutrition of the cows and the method of protein extraction.
So make sure you are not going cheap when it comes to protein supplementation. If you are going to put it into your body then make sure you are doing the research and asking the right questions prior to consumption.