As scientific techniques progress, technology allows us gain a deeper insight into the world around us. We have space missions searching for life on other planets, archeologists trying to piece together the remains of monstrous creatures from the distant past, and then we have scientists who work on milk.
It might not sound glamorous to an outsider, spending a good deal of your life thinking about the back end of a cow, but incredibly, after humans have used milk for hundreds, even thousands of years, researchers working on casein which is the major protein in milk, recently made an incredible discovery which has the potential to impact a lot of people.
A small protein fragment (or peptide) found in casein has been found, in initial experiments, to have an anti-hypertensive effect, which means it can lower the blood pressure. The effect was noted when the compound was delivered intraveneously. There are a lot of compounds, particularly protein based compounds, that lose their effectiveness when they pass through the digestive system, which is the reason that some vaccines and medications are given by injection instead of orally.
Obviously intravenous milk is a long way from catching on, so the next step was to see if this antihypertensive peptide was destroyed by the digestive process. A group of scientists decided to try this out using rats. The rats were fed the protein fragment, and the scientists monitored its appearance in the bloodstream. The researchers found that the protein fragment was able to pass through the digestive system and into the bloodstream intact at a low but significant rate. This is great news, because it means that there is potential to develop this technology into a functional food, or an oral supplement or medication.
There is still a massive amount of research needed before anything like that will happen, including trials in humans. We will not know if the casein found in milk or in casein supplements has any effect on hypertension in humans until these experiments have been done. Nonetheless, this research in mice is an important first step.
Many people use casein as a night time protein, because of its special structural properties, which cause it to agglutinate in the stomach and digest very slowly, keeping the body in positive nitrogen balance while the muscles repair and recover overnight. Because it is so filling, it is a good choice for dieters. High in BCAAs, rich in calcium, with one of the best biological values out of all protein types, casein has a long list of attributes. It's early days yet, but we may be able to add another attribute to this list in the future.
Sanchez-Rivera L, Ares I, Miralles B, Gomez-Ruiz JA, Recio I, Martinez-Larranaga MR, Anadon A, Martínez MA. Bioavailability and Kinetics of the Antihypertensive Casein-Derived Peptide HLPLP in Rats. J Agric Food Chem. 2014 Nov 11.