Proteins are an essential component of all life. They are present in the material of plant and animal origin.Maximum protein concentration present in the muscle (red and white meats and fish). Leguminous plants, such as (beans) have the ability to bind free nitrogen from the air, which contain high levels of protein.
Nuts are also a good source of protein. Other good sources of protein are eggs, milk and cheese. To also include are milk protein casein, lactalbumin and whey protein, which often are part of nutritional supplements for use in supporting food. The whole grains and vegetables also provide the protein, but in smaller quantities.
Proteins serve many functions:
It is assumed that an adult in a healthy, normal weight should consume 0.8 – 1g protein per 1kg of body weight. to increase muscle mass it is recommended to intake 1.8 – 2.4g protein per 1 kg of body weight.