What is Casein Protein? – Ultimate Casein Protein Guide

In the highly competitive world of sports supplementation, there’s one supplement that reigns supreme. That supplement is whey protein. Whilst whey grabs all of the headlines and gets all of the attention, there’s another equally as beneficial protein hiding in the shadows. That protein is casein. Casein is like the Batman of the supplement world. It’s there to help and do good, not to gain credit or recognition.

Casein simply does what it is designed to do. But what is casein protein and what exactly is it designed to do? If you are into your training and are looking to build muscle, if your supplement stack doesn’t contain casein protein, you may wish to rectify this ASAP. Here is the ultimate guide to casein.

What is casein protein?

Casein protein is a highly-beneficial yet vastly underrated protein supplement. Just like whey, it too is derived from cow’s milk. In fact, of the total protein content found in milk, casein makes up roughly 80%. The final 20% comes from whey. It provides the exact same amino acid profile as whey protein, yet it behaves very differently in the body.

When enzymes are added to milk to cause it to split, it separates into solid curds, and liquid whey. The solid curds are where the casein protein is found. It has a thicker, more gelatinous structure, which means that, once processed and filtered into a protein powder, it is absorbed differently to whey. Whey is a fast-absorbing protein whereas casein is absorbed much slower.

Why use casein when you already have whey?

A lot of people tend to favour whey protein over casein, and as they are already using one protein supplement, surely, they don’t need to use another as well? Well, actually they do. You see, casein behaves very differently in the body when compared with whey.

Whey is a rapid-absorbing protein that quickly enters the cells in your muscles after being consumed. While beneficial at certain times, it does mean that the protein is used up very quickly. Casein on the other hand, is a slow-digesting protein, so it is absorbed at a much more lethargic pace. This is very beneficial at certain times of the day, and the night. You see, without proteins and the amino acids making up the proteins, your body goes from being in an anabolic (muscle building) environment to a catabolic environment. When your body is catabolic, your body actually breaks down its own muscle tissues for fuel when no other energy is available.

This is why people drink a casein protein before bed. This slow-release protein provides a slow and gradual release of proteins and amino acids as you sleep, helping to stave off muscle catabolism and ensuring you remain in an anabolic environment. To cut a long story short, casein provides a trickle of proteins and amino acids for your muscles when you sleep, or simply during long durations where you don’t have access to whole foods and proteins. A whey protein shake before bed would be used by the body at a much quicker rate, which is why casein is preferred in these instances.