Diet, nutrition, and breastfeeding

Advise your lactating patients to focus on enjoyment of a wholesome and varied diet

Here are sensible dietary recommendations for breastfeeding women.

• Focus on enjoyment of a wide variety of culturally appropriate foods, with an emphasis on unrefined, plant-based foods (fruits, vegetables, grains, legumes).

• Limit foods and drinks containing saturated fat, added salt, and added sugars.

• Minimise juice intake to one glass of freshly squeezed or pulp-rich juice daily and otherwise drink plenty of water. Also, have water on hand when breastfeeding as commonly women feel thirsty with milk ejection.

• Enjoy modest (not excessive) coffee intake. There is also usually no need to cease coffee altogether, as coffee has not been shown to result in unsettled infant behaviour.

• Enjoy intermittent 'treats' (e.g. chocolate bar or sweets or dessert once or twice or a few times a week), rather than aiming for a 'perfect' diet without treats. This is because rigorous attempts to avoid treats commonly result in binges on sweets!

• Regularly expose the skin to daylight for both mother and infant, complying with principles of safe sunlight exposure. This will help protect vitamin D levels. This is consistent with the Possums programs daily focus on rich and changing sensory motor nourishment outside the home.

• The National Health and Medical Research Council Public Statement (2010) Iodine Supplementation for Pregnant and Breastfeeding Women continues to recommend 150 mcg iodine supplementation daily for lactating women. Women with known thyroid conditions should seek advice from their medical practitioner before taking an iodine supplement.

• There is no safe level of alcohol for developing and breastfeeding babies, so health authorities usually advise that pregnant and breastfeeding women don't drink alcohol. However, a risk minimisation (rather than risk elimination) approach may be more clinically appropriate. There is more on alcohol and breastfeeding here.

Do lactating women need to eat more?

The Australian National Health and Medical Research Council notes that a woman requires an additional 2.1 MJ and a slight increase in protein intake during lactation to maintain her body weight (NHMRC 2006). The Australian Breastfeeding Association notes that this is the equivalent "to an additional two Weet-Bix with a cup of milk, a banana, and a handful of nuts". (Bando)

Importantly, this is not clinically useful information for our patients, who do not benefit from advice to "eat more for the baby" whilst lactating. Instead, women can be encouraged to enjoy wholesome food and to listen to their own body.

Be mindful that there are risks associated with conducting detailed dietary analysis and giving prescriptive dietary advice during breastfeeding

There are risks associated with routine over-analysis of breastfeeding patients' dietary needs and eating patterns (unless she has specific risk factors). Analysing caloric intakes and micronutrient proportions in a breastfeeding woman's diet, accompanied by detailed dietary recommendations, may accidentally contribute to the hypervigilant, anxious, or distressed cognitions about food which are already prevalent amongst women due to sociocultural exhortations re ideal bodily appearance, body size, 'healthy lifestyle', and body shape.

For example, it is now widely accepted that a clinician's recommendations to restrict calories for weight management has typically resulted in the patient gaining weight long term.

Similarly, overtreatment with detailed dietary recommendations for breastfeeding women (except in those circumstances of the patient who is also dealing with a serious medical condition which requires the support of a dietician or nutritionist) risks unintended consequences.

Please see Dr Kate Rassi's work in the NDC Lactation Module on Synchronising milk production with infant caloric need for more on obesity and weight loss during lactation.

Background information for breastfeeding support professionals

The concentrations of maternal dietary nutrients found in breastmilk is highly variable

There is increased maternal nutritional demand during lactation relative to the nutritional demands of pregnancy.

1. This is particularly true for vitamins A, B group, C, D, E, and zinc.

2. The concentration of some nutrients, such as B vitamins, vitamin A, iodine, and selenium are highly variable in breastmilk and dependent on maternal intake.

3. Maternal diet does not impact upon breastmilk concentrations of folic acid, vitamin D, calcium, iron, copper, and zinc.

4. An adaptive mechanism protects the infant from deficiencies, though the mother is at risk of deficiencies herself if her dietary intake is insufficient.

5. Although total concentration of fat in breastmilk is not related to maternal dietary intake, the relative proportion of omega-3, omega-6, and trans fats depends on dietary intake.

6. Iron, calcium, copper, and zinc breastmilk concentrations reduce during lactation from 11 to 17 months and likely beyond (Perrin et al 2017).

7. Other nutrients, such as total protein and lactoferrin, increase into the second year of lactation (Perrin 2017).

Useful extracts from Perichart-Perera 2025 on optimal nutrition in lactation

The most common maternal nutritional imbalances which affect human milk composition are

• Anaemia

• Iron deficiency

• Low serum Vitamin D, A

• Iodine deficiency.

Human milk provides all essential nutrients and bioactive molecules needed for optimal infant health and development. Adequate maternal nutrition prevents alterations in maternal nutritional status and avoids nutrition and metabolic imbalances. Breastfeeding is a highly demanding physiological stage, characterised by high energy and nutrient requirements. However, in many countries, unhealthy diets providing excessive intakes of energy, fat, saturated fat, added sugars, and with low nutrient density and fiber, are frequently consumed and have been considered risk factors for multiple chronic diseases.

The leading cause of multiple micronutrient deficiencies is a poor-quality maternal diet. Inadequate intake of animal protein in developing countries or high prevalence of vegetarian/vegan diets in high-income countries are associated with lower micronutrient intakes in pregnancy and lactation. A high intake of phytates or polyphenols is also typical in vegetarian/vegan diets (legumes and unrefined grains), affecting the absorption of some nutrients.

The micronutrients that are more frequently consumed below the recommended intakes are vitamin A, vitamin D, folate, vitamin B1, vitamin B6, calcium, zinc, potassium, and selenium, which may result in developing nutrient deficiencies. Breast milk content of some B-complex vitamins (thiamin, riboflavin, vitamin B6, and vitamin B12), vitamin A, vitamin D, vitamin E, iodine, and selenium represent the primary source for the infant and appear to be dependent on the maternal diet or status of these vitamins. Maternal dietary intake or nutrition status of folate, calcium, iron, copper, and zinc do not appear to influence breast milk concentration of these nutrients.

A 2024 systematic review (27 observational studies, 7 intervention studies) corroborated the positive association between maternal fish and long-chain polyunsaturated fatty acids (LCPUFAs) intake with breast milk concentration of these fatty acids and particularly DHA and EPA. The evidence regarding other nutrients was highly variable and the observed methodological limitations in the studies (time of postpartum, sampling techniques, low quality) did not allow us to draw strong conclusions.

Anemia is still a significant health problem, and women of reproductive age are particularly vulnerable. Higher levels of food insecurity, low iron intake, gynecological disorders, and maternal hemorrhage are the main determinants of anemia in these women. Studies from high-income countries have reported 10–30% prevalence of postpartum anemia; higher numbers are expected in low and middle income countries (LMICs).

Iron, iodine, vitamin A, and vitamin D deficiencies are still highly prevalent worldwide and primarily affect women and individuals from LMICs.

Selected references

Abe SK, Balogun OO, Ota E, Takahashi K, Mori R. Supplementation with multiple micronutrients for breastfeeding women for improving outcomes for the mother and baby. Cochrane Database Syst Rev. 2016;2(2):CD010647. https:/doi.org/10.1002/14651858.CD010647.pub2

Bando, Nicole. "Breastfeeding: when vitamin and mineral supplementation is required", Australian Breastfeeding Association Factshee for Health Professionals. Date unknown.

Favara G, Maugeri A, Barchitta M. Maternal lifestyle factors affecting breast milk composition and infant health: a systematic review. Nutrients. 2025;17(62):https://doi.org/10.3390/nu17010062.

Jimenez MPH, De la Calle S, Vives CC, Saez DE. Nutritional supplementation in pregnant, lactating women and young children following a plant-based diet: a narrative review of the evidence. Nutrition 2025;136:112778.

Kankaew S, Briere C-E. Maternal nutrition and human milk nutrients: a scoping review. American Journal of Maternal and Child Health Nursing. 2025;50(1):doi: 10.1097/NMC.0000000000001059.

National Health and Medical Research Council. (n.d.). Healthy eating when you’re pregnant or breastfeeding. Eat for Health. https://www.eatforhealth.gov.au/eating-well/healthy-eating-throughout-all-life/healthy-eating-when-you’re-pregnant-or-breastfeeding

National Health and Medical Research Council. (2012). Infant Feeding Guidelines. Information for health workers. https://www.nhmrc.gov.au/about-us/publications/infant-feeding-guidelines-information-health-workers#block-views-block-file-attachments-content-block-1

National Health and Medical Research Council. (2010). Public statement: Iodine supplementation for pregnant and breastfeeding women. https://patientinfo.org.au/patientinfo/NHMRC%20Iodine%20Supplementation%20Fact%20Sheet.pdf

Perichart-Perera O. Nutrition for optimal lactation. Annals of Nutrition and Metabolism. 2025:DOI: 10.1159/000541757.

Perrin a, Fogleman A, Newburg D, Allen J. A longitudinal study of human milk composition in the second year postpartum: implications for human milk banking. Maternal and Child Nutrition. 2017;13(1):e12239. doi: 12210.11111/mcn.12239.