Maternal nutrition during pregnancy and/or lactation is highly important in the case of fetal programming and epigenetic regulation. Moreover, it is related to the adequate development of the fetus, infant and future adult. Breast milk is the optimal form of infant nutrition for the first six to twelve months of life, providing both short-term and long-term advantages for infants and mothers. Among other benefits, breastfeeding provides the infant with protection from a variety of infections, including recurrent otitis media, gastroenteritis, and respiratory tract infections. Chapter One in this book evaluates the correlation between the nutritional status of breastfeeding women, and the cholesterol concentration in their milk. Chapter Two reviews maternal viral infections that can be transmitted to infants directly through breast milk or other mechanisms associated with breastfeeding. Chapter Three discusses the application of hydrostatic high pressure treatments for improving the quality of banked human milk. Chapter Four analyses scientific works published in periodicals indexed in electronic databases about the importance of a social support network to the donation of human milk through the partnership between Brazilian Human Milk Banks and the Military Firefighters Corps for receivers of human milk, counting from the network’s first registered existence in Brazil until the year of 2015, and considering its social effects in the country and perhaps abroad.