Breastfeeding Diet · What Is It, Foods to Avoid, and More

Breastfeeding or lactation refers to the process by which infants attach to the breast to obtain breast milk. All newborns from birth to at least 6 months of age are encouraged to receive their nutrition exclusively from breast milk, if possible.   

Milk production is regulated by maternal hormones derived from the hypothalamus and pituitary gland. The two main hormones involved in milk production and ejection are prolactin and oxytocin. While prolactin aids in milk synthesis, oxytocin induces the breast to pump out the milk. Additionally, the let-down reflex also triggers the release of breast milk. This reflex is triggered when tiny nerves are activated as the infant breastfeeds, releasing prolactin and oxytocin into the bloodstream. 

Colostrum is the first milk produced after delivery, and it is high in protein, sodium, and immunoglobulins, while being low in lactose, which facilitates digestion for the infant. After 30 to 40 hours postpartum, the milk composition changes by increasing lactose concentration and diluting other constituents, such as macronutrients (e.g., proteins, fatty acids) and micronutrients (e.g., vitamins A, B1, B2, B6, B12, D, and iodine). 

Subsequently, the maintenance of lactation follows an autonomous pattern whereby the sucking motions of the baby and emptying of the breast are the main factors regulating milk supply. 

Individuals do not need to limit their diets while breastfeeding, but are encouraged to eat healthy and diverse meals. Nonetheless, certain foods and drinks, like fish, caffeine, and alcohol, should be consumed in limited amounts. 

Although fish remains an excellent source of protein and contains essential vitamins and minerals for breastfeeding individuals, care may be taken in deciding the quantity and type of seafood to consume. In general, pregnant or breastfeeding individuals are recommended to eat two to three servings, corresponding to eight to twelve ounces, of different kinds of fish per week. Most fish contain some amount of mercury, which accumulates in their flesh and can pass from lactating person to infant through breast milk. Fish high in mercury such as tuna, mackerel, shark, swordfish, or tilefish, are typically advised to be avoided, as increased mercury could have adverse effects on the brain and nervous system of the breastfed infant.  

Caffeine passes from the lactating individual to the infant in small amounts through breast milk. Usually, it does not adversely affect the infant when consumed in low to moderate amounts (i.e., about 300 milligrams or two to three cups of coffee). Irritability, poor sleeping patterns, and fussiness have been reported in infants of lactating individuals with very high intakes of caffeine (i.e., about 10 cups of coffee or more per day). If an infant appears to be more fussy or irritable after high caffeine consumption, a decrease in caffeine intake may be considered. Preterm and younger newborn infants break down caffeine slowly, so individuals who are breastfeeding these infants might consider limiting or avoiding their caffeine consumption. 

When consuming alcohol, a small percentage is transferred into breast milk; however, as the alcohol is cleared from the bloodstream, its concentration in the milk also diminishes. The amount of alcohol considered to be safe while breastfeeding is controversial. Several factors affect how much alcohol is transferred to breast milk and how much the baby absorbs. One serving of alcohol is about 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of 80-proof liquor. To completely avoid any alcohol being transferred to the baby, it is recommended to wait approximately two hours per serving, after drinking alcohol, before breastfeeding. Once the threshold of two hours has passed, breastfeeding may be allowed, and it is likely unnecessary to pump and discard the milk.