The biggest source of protein from colostrum comes in the form of antibodies or immunoglobulins. They make up 70-80% of the protein in colostrum. IgG makes up the biggest portion of about 75% of total antibodies in colostrum.
What are antibodies? Proteins our body makes that recognizes an antigen on the outside of a foreign invader like a virus or bacteria. An antibody binds to an antigen and invokes an immune response telling our body to get that bacteria/virus out of our body. Since colostrum is high in antibodies, it's been shown to increase protection from bacteria and viruses.
