It has been indicated that optimal maternal nutrition, or lack thereof, affects the composition of breast milk. However, most research has reported an association between breast milk quality and nutrition without directly assessing dietary habits of the mother. Therefore, the following will consider the research concerning said connection between milk composition, supplementation, contraindications, and maternal dietary habits.
Breast milk provided from well-nourished and healthy mothers is considered the best food choice for infants, and is exclusively recommended for the first 6 months of life (Bravi et al., 2016). Interestingly, human milk is a nutritionally dynamic food and its composition is affected by feeding frequency, duration of feeding, time of day, and over lactation (Bravi et al., 2016). Other factors affecting breast milk include infant sex, maternal lifestyle, and infective status. In essence, breast milk is in an almost constant flux due to the aforementioned factors.
Bravi et al. (2016) performed a systematic review including 36 publications that met their inclusion criteria. Within the 36 reviewed articles, 3 articles held the highest evidence for the influence of fish consumption upon the levels of docosahexaenoic acid (DHA) in breast milk. Finally, another 2 studies supported strong correlations between dietary vitamin C and associated concentrations in breast milk (Bravi et al., 2016). Such research helps support the influence of diet upon breast milk composition. Having established the influence maternal nutrition, it is then necessary to indicate general guidelines during lactation.
Brown (2014) indicated that mothers within normal weight parameters usually spend approximately 500 cal/day upon milk production within the first 6 months of breastfeeding, and 400 cal/day thereafter. Thus, the daily recommended intake (DRI) to help balance additional energy costs of the mother include at least 330-450 cal/day (Brown, 2014).
Although most macronutrients and micronutrients are found within whole food consumption, Brown (2014) did indicate persisting deficiencies within breast milk. Such a deficiency included vitamin K, which has been associated with vitamin K deficiency bleeding (VKDB) among infants. As such, vitamin K supplementation has been recommended for newborns to attenuate said deficiency (Brown, 2014).
Vitamin D is a second vitamin deficiency found in breast milk and has also been associated with rickets in infants (Brown, 2014). Vitamin D is paramount because deficiencies have also been associated with type 1 diabetes, multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease, and overall cancer mortality (Gissel, Rejnmark, Mosekilde, & Vestergaard, 2008). Thus, Brown (2014) indicated that a minimum intake of 400 IU/day of vitamin D.
Although some supplementation has been suggested for breastfeeding mothers, other forms of supplementation have been contraindicated. Iron supplementation, for example, has not been advised since deficiencies are not normally observed in breast milk (Brown, 2014). Fortified human milk substitutes (HMS) have excess iron and is thought to bind to lactoferrin (involved in immune function) inhibiting its function (Brown, 2014).
In conclusion, healthy dietary habits have been shown to influence breast milk composition. Most mothers are not required to drastically alter their diets unless a deficiency has been found (i.e., vegans may need additional supplementations if they do not consume dairy and eggs) although trends indicate vitamin K and D deficiencies. If the mother ingests adequate amounts of proteins (seafood, poultry, lean meats, nuts, seeds), and carbohydrates (vegetables and fruits), and essential fats (i.e., EPA, DHA) milk quality is likely to sustain the infant both short term and long term (Brown, 2014).
References
Bravi, F., Wiens, F., Decarli, A., Dal Pont, A., Agostoni, C., & Ferraroni, M. (2016). Impact of maternal nutrition on breast-milk composition: A systematic review. The American Journal of Clinical Nutrition, 104(3), 646-662.
Brown, J. E. (2014). Nutrition through the life cycle (5th ed.). Stamford, CT: Cengage Learning.
Gissel, T., Rejnmark, L., Mosekilde, L., & Vestergaard, P. (2008). Intake of vitamin D and risk of breast cancer- A meta-analysis. The Journal of Steroid Biochemistry and Molecular Biology, 111(3-5), 195-199.
-Michael McIsaac