What Is It, Foods to Avoid, and More
Author:Nikol Natalia Armata, MD
Editors:Alyssa Haag,Emily Miao, PharmD,Kelsey LaFayette, DNP, ARNP, FNP-C
Illustrator:Jessica Reynolds, MS
Copyeditor:Stacy Johnson, LMSW
What is breastfeeding?
Breastfeeding or lactation refers to the process during which infants attach to the breast to obtain breast milk. All newborns from birth to at least six 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 are oxytocin and prolactin. While prolactin aids in milk production, oxytocin induces the breast to pump out the milk. Additionally, the let-down reflex also triggers the release of breast milk. This reflex occurs 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 low in lactose, making digestion easier. 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 the milk supply.
What is a breastfeeding diet?
Breastfeeding individuals generally need to increase their caloric intake to meet their dietary needs. An additional 330 to 400 kilocalories (kcal) per day is recommended for well-nourished, breastfeeding individuals, compared with the amount they consumed before pregnancy. For example, approximately 2,000 to 2,800 kcal per day is typically needed for breastfeeding individuals, whereas around 1,600 to 2,400 kcal per day is generally needed for non-pregnant individuals who are not breastfeeding. The number of additional calories required by an individual who is breastfeeding is also affected by their age, body mass index, activity levels, and extent of breastfeeding (i.e., exclusively breastfeeding versus breastfeeding and formula feeding).
Iodine and Choline
Iodine is a mineral responsible for thyroid hormone synthesis, which supports neurodevelopment in the infant. Similarly, choline is a mineral that promotes the development of the infant’s organs. A breastfeeding individual’s need for iodine and choline increases during lactation to provide sufficient amounts for the individual and infant. The Dietary Guidelines for Americans recommend that lactating individuals consume 290 mcg of iodine and 550mg of choline daily throughout the first year postpartum.
Pregnancy and lactation cause a temporary decrease in bone mass, as increased needs of calcium for the rapidly mineralizing fetal skeleton are primarily drawn from the mother’s reserve, causing a 3-5% loss in the mother. Although bone mass is usually regained after breastfeeding stops, mothers can prevent this loss by consuming additional calcium through food and beverages during pregnancy and lactation. All adult individuals capable of pregnancy are advised to consume a minimum of 1000 mg of calcium a day before pregnancy and during pregnancy and breastfeeding. These recommendations are the same for those who are not pregnant or breastfeeding.
Vitamin D is a vitamin necessary to absorb calcium and maintain healthy bones. Vitamin D-fortified milk is a good source of dietary vitamin D, providing approximately 100 international units (i.e., 2.5 micrograms) per cup. Both breastfeeding and non-breastfeeding individuals capable of pregnancy typically require an estimated 600 international units (i.e., 15 micrograms) of vitamin D per day.
Iron is a mineral needed to produce hemoglobin, a protein in red blood cells that carries oxygen. The recommended dietary allowance of iron for lactating individuals is 9 mg daily, compared with 18 mg for adult individuals assigned female at birth who are not breastfeeding. Because lactating individuals no longer have the increased blood volume related to pregnancy or typically are not menstruating during lactation, they require less iron.
Omega-3 fatty acids are healthy fats located in high amounts in the eyes and brain that are essential to cell structure and function. The recommended intake of omega-3 fatty acids during lactation is 200 to 300 mg daily, which can typically be met with one to two servings of fish per week.
How does a breastfeeding diet support breastfeeding?
Appropriate breastfeeding nutrition in the lactating individual will help the individual and provide the baby with nutrients to promote its growth and overall health. Breastfeeding individuals are generally advised to follow a healthy, well-balanced diet that includes dairy, meat, fish, and other vitamins- and mineral-rich foods. The breastfeeding individual’s nutrition affects the content of their milk, including the contents of vitamins and minerals (e.g., vitamin A, thiamin, riboflavin, vitamin B6, vitamin B12, selenium, and iodine). If the individual's diet alone does not cover the needs of the individual or baby, the mother may need supplements to ensure good milk quality and quantity. Restricted diets (i.e., vegetarian or vegan) may cause nutrient quantity concerns. Therefore individuals who follow restricted diets may be recommended to see healthcare providers regularly if they need any specific supplements. People who follow a vegan diet usually need to take a vitamin supplement containing vitamin B12.
What foods are best on a breastfeeding diet?
The most crucial goal of a breastfeeding diet is to be nutritionally balanced, which includes a variety of fruit and vegetables as vitamin and mineral sources, lean protein, healthy fats, and whole grains, an important energy source. Iodine, essential for the baby’s brain development, can be found in dairy products, eggs, seafood, or in iodized table salt. In contrast, choline can also be found in dairy and protein food groups, such as eggs, meats, seafood, beans, peas, and lentils. The primary sources of calcium in the diet are milk and other dairy products, such as cheese or yogurt, as well as calcium-fortified foods, such as orange juice or tofu. There are also smaller quantities of calcium in leafy green vegetables, such as spinach. The human body mainly produces vitamin D when exposed to sunlight; however, there are also nutritional sources of vitamin D. The flesh of fatty fish such as trout, salmon, cod, and haddock, as well as fish liver oils, are among the best sources.
Additionally, beef liver, egg yolks, and cheese also have small amounts of vitamin D. Lastly, mushrooms may provide variable amounts of vitamin D.
What foods should be avoided on a breastfeeding diet?
Individuals do not need to limit their diets while breastfeeding but are encouraged to eat a healthy and diverse diet. 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, two to three servings, or between eight and twelve ounces, of different kinds of fish are recommended to eat per week for those who are pregnant or breastfeeding. Most fish contain some amount of mercury, which accumulates in their flesh and can pass from mother to infant through breast milk. Fish with high levels of mercury, such as tuna, mackerel, shark, swordfish, or tilefish, are typically advised to avoid as increased mercury could have adverse effects on the brain and nervous system of the breastfed infant.
Caffeine passes from the mother to the infant in small amounts through breast milk. Usually, it does not adversely affect the infant when the mother consumes 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 mothers with very high intakes of caffeine, about ten cups of coffee or more per day. If an infant appears to be more fussy or irritable after consuming high amounts of caffeine, a decrease in caffeine intake could be considered. Preterm and younger newborn infants break down caffeine slowly, so mothers of these infants might consider limiting or avoiding their caffeine consumption.When consuming alcohol, a small percentage is transferred into breast milk; however, when the alcohol is cleared from the bloodstream, it is also cleared from the milk. 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, five 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.
What are the most important facts to know about a breastfeeding diet?
A breastfeeding diet is the recommended nutrition for a breastfeeding parent to cover all the nutritional needs of the developing baby. Healthy foods for breastfeeding individuals and babies typically include dairy, meat, fish, and another vitamin- and mineral-rich foods. Nutrition of the breastfeeding individual is essential as their diet affects the content of their milk, including vitamins and minerals, especially iodine, chlorine, calcium, and vitamin D. As such, caution may be taken in the amounts of fish, caffeine, and alcohol consumed.
Watch related videos:
Related linksAnatomy of the breast
Oxytocin and prolactin
Resources for research and reference
Ballard, O., & Morrow, A. L. (2013). Human milk composition: nutrients and bioactive factors. Pediatric clinics of North America, 60(1), 49–74. https://doi.org/10.1016/j.pcl.2012.10.002
Butte, N. F., & Stuebe, A. (n.d.). Patient education: Health and nutrition during breastfeeding (Beyond the Basics). UpToDate. Retrieved October 2, 2022, from https://www.uptodate.com/contents/health-and-nutrition-during-breastfeeding-beyond-the-basics#H17
Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Iodine. [Updated 2022 Sep 19]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501477/
Kalarikkal SM, Pfleghaar JL. Breastfeeding. [Updated 2021 Jul 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534767/
U.S. Department of Health and Human Services. (n.d.). Office of dietary supplements - vitamin D. NIH Office of Dietary Supplements. Retrieved October 11, 2022, from https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/