Colostrum Colostrum is the “first food of life” because it is excreted from the mammalian breast during the first 72 hours after birth. It is rich in nutrients and substances called immunoglobulins and lactoferrin. Immunoglobulins and lactoferrin support the maturation of the immune system, a process that is not completed until the second year of life in humans. Visit - https://www.nationalnutrition.ca/articles/supplements/colostrum/