Casein is a protein which is found in large amounts in the cow's milk, and is digested slowly by the body. In fact, about 80% of the proteins that we get from cow's milk is casein. It is extracted from cow's milk through a process known as ultra filtration. The good thing about this extraction is that the process is entirely chemical free. This protein helps in the proper muscle development of the body, and also helps in releasing the amino acids steadily from the body. There are two types of protein present in the milk: whey protein and casein protein. While the former is digested quickly by the body, the latter takes time. The reason why this protein is digested slowly by the body is because it forms a gel in the intestine. This gel slowly releases the various amino acids in our blood, which enables it to curb the breakdown of protein in the body. It also ensures that our body gets its required supply of the proteins, even after the whey protein is digested by the body within 45 minutes after consumption. When we sleep at night, our body does not get fed for about 8 hours. Consumption of this protein just before sleeping enables the body to receive nutrients for the next 7 hours and hence, does no create any hunger pangs in the night. And as aforementioned, the milk contains a lot of casein. However, experts suggest that for the correct effect of this protein in the body, it is necessary to take this protein along with whey protein. Other than milk, cheese, farmer's cheese, or cottage cheese are also good sources of this kind of protein. Yogurt is another source of this protein. Any dairy product will have this protein in some amount. Hence, eating a cheese cube or having a glass of milk, makes you feel full for quite a few hours. Other than these, the protein powder is another good source of this protein. A scoop of this protein powder in a glass of milk makes a powerful snack. This is the reason why such kinds of protein powders are used in muscle-building. Many protein snack bars which are high in nutritional value, also contain this protein. Side Effects Too much of this protein may lead to various side effects. Consumption of this protein through protein shakes increases the nitrogen level in the body. Hence, it is recommended to drink plenty of water to avoid any side effect. In some studies, it has been found that women lose calcium when they consume this protein. Since calcium is important for the body, it is not a desirable situation. Other than these, there are no other well-known side effects. However, if one is affected by a casein allergy, it is recommended that he/she should refrain from consuming any foods that contain this protein. Another point to remember is that one should not consume it in high doses. Use only a small amount daily to avoid any side effects. As aforementioned, it is a good protein and as it is digested slowly by the body, it is ideal to be consumed during the night to enable the body to feel full. However, take care not to consume this protein in excess. Disclaimer: This Buzzle article is for informative purposes only, and should not be used as a replacement for expert medical advice.