Infant mortality and morbidity research is vitally concerned with breastfeeding since childhood under nutrition is one of the biggest public health issues. Globally, early, exclusive, and continuous breastfeeding for 23 months dramatically lowers newborn and child mortality, according to consistent and considerable data. There is a vast amount of scientific knowledge and information available regarding the biochemistry of human milk. The newborn receives both nutritional and non-nutritive signals from human milk. Human milk is a fluctuating mammary gland secretion rather than a constant bodily fluid. Hind milk and foremilk are distinct. Compared to transitional and mature milks, colostrum is different. Milk varies depending on the time of day and over time. Physical qualities including osmolarity and pH alter as protein, fat, carbohydrate, mineral, and cell contents vary. Many constituents play multiple roles, including those related to immunity, nutrition, and infection protection. They can also have a variety of additional impacts.