Vitamin D and Breastfeeding

Vitamin D is making headlines as more and more information is emerging about its effects on the human body. Mothers often ask how they can get enough vitamin D or if supplemental vitamin D is really necessary.  It is not possible to offer comprehensive information on every issue surrounding vitamin D and motherhood in a short article, but we have provided answers to some common questions below. Please read the “more info” links for further details.

Please note that the information provided below is solely for general education purposes and is not intended to be medical advice, nor is it a substitute for medical advice. Talk to your health care provider or traditional healer about personal health questions or concerns.

What is vitamin D?

Vitamin D is a pre-hormone made by the body when the skin is exposed to ultraviolet light (sunshine). It can also be obtained from some foods as well as vitamin D3 supplements. Vitamin D is fat-soluble, which means it is stored in the liver and fatty tissues.

More info–Read on to find out how the body makes vitamin D from sunlight:
National Institutes of Health: Vitamin D Supplement Fact Sheet

Oregon State University Micronutrient Information Center: Vitamin D

Why all the buzz about vitamin D?

You may have heard about the recent controversies over how much vitamin D people need in order to maintain good health and whether or not supplemental vitamin D is necessary. Some health experts report that for most healthy people, vitamin D from sunlight and food is enough.  Others report that because vitamin D intake is critical, and many people are deficient without knowing it, supplementing is more or less an issue of public health. One thing is for certain: vitamin D is vital to life processes within the human body. For example, vitamin D is necessary for your body to absorb calcium and phosphate from the intestines. Because Vitamin D determines how well calcium and phosphorus are absorbed, it must be present in large enough amounts to allow the body to build strong bones and to recalcify (restore lost calcium salts to) adult bones.  Recent research shows that a low level of vitamin D may also be a factor in high blood pressure, diabetes, depression, cancer, neuromuscular disease, chronic inflammation, and myriad health issues.  Researchers have even found that vitamin D promotes normal cell growth and differentiation (process by which cells become specialized) and is an important factor in maintaining hormonal balance and a strong immune system. Researchers believe that vitamin D actually becomes a building block of cells and assists in the buildup and breakdown of tissue. In short, vitamin D plays a key role in regulating the processes that keep us well. No wonder there is so much interest in this topic!

More info:
Harvard School of Public Health: Vitamin D and Health

What are some sources of vitamin D?

  • exposure of the skin to sunlight
  • fatty fish such as salmon, lake trout, cod, and mackerel
  • cod liver oil
  • certain animal fats, such as seal blubber
  • egg yolks
  • organ meats, such as liver
  • artificially fortified foods such as dairy milk, margarine, and cereals
  • vitamin D3 supplements

More info:
National Institutes of Health: Vitamin D Supplement Fact Sheet

Oregon State University Micronutrient Information Center: Vitamin D

Is breastmilk vitamin D deficient?

Breastmilk is species-specific nutrition and contains all the necessary nutrients in the right amounts for proper growth and development. Mothers sometimes ask: if breastmilk is “perfect,” why is there concern about the low level of vitamin D in breastmilk? The issue is more complex than it may seem. Some experts infer that because the normal levels of vitamin D in breastmilk are not “high,” even when the mother’s own vitamin D levels are normal, that the vitamin D in breastmilk is not meant to be the sole source of the nutrient. Rather,  it is enough to supplement vitamin D made by the skin of infants who are routinely exposed to sunlight.

It is possible that breastmilk, which contains about 25-78 IU of bioavailable vitamin D per liter, combined with adequate sunlight exposure could provide sufficient vitamin D. Breastmilk contains sufficient levels of vitamin D as long as the mother has adequate vitamin D stores. The problem is that, due to modern lifestyles (insufficient sunlight exposure, diets deficient in vitamin D), many mothers do not have adequate vitamin D stores, and the amount of vitamin D in breastmilk is influenced by the mother’s own vitamin D stores.

Because individual mothers may have low vitamin D stores, they may have less vitamin D in their breastmilk. Additionally, in modern society, mothers and babies are less likely to get the amount of sunlight needed to help fill their vitamin D requirements and build adequate stores. The reason for the broad recommendation for prophylactic (preventive) vitamin D supplementation of breastfed infants is not that breastmilk is deficient but that modern lifestyles have put mothers and babies at greater risk to have insufficient vitamin D. Less sun exposure, recommended use of sunscreen, and less consumption of foods naturally rich in vitamin D are all factors in vitamin D insufficiency.

What does a diet of indigenous foods have to do with the vitamin D levels of pregnant and lactating women?

A study by Weiler et al. showed that indigenous Canadian women who ate the same foods as their non-native counterparts had lower vitamin D levels. In this study, it was clearly shown that a traditional Inuit diet provides a nutritional harmony that is unfortunately not possible with store-bought foods such as hot dogs, potato chips, snack cakes, boxed dinner kits, and other processed foods. In extreme northern climates, Native people have very wisely harnessed vitamin D from traditional foods such as seal, whale, lake trout, and animal fats or fish fats. These are all foods that are naturally high in vitamin D and critical to health in areas that receive little sunlight. When women work to bring more native foods into their diets, they effect positive change in the health of their families and themselves.

Here’s how one community is getting the message out:
Department of Health and Social Services Nunavut: We need vitamin D for strong bones and teeth

What are some risk factors for vitamin D deficiency?

Issues that affect levels of sun exposure:

  • dark skin pigmentation
  • living in north of 34 degrees latitude (roughly anywhere north of Atlanta, GA)
  • spending little time outdoors (limited sun exposure)
  • keeping skin mostly covered with clothing when outdoors
  • using sunscreen (for example, 30 SPF sunscreen blocks 97 percent of the UVB rays)
  • living in areas with heavy air pollution
  • living in latitudes that receive little or no sunlight for part of the year

Factors that affect the amount of vitamin D taken in from food:

  • strict vegan diet
  • diet of mostly processed foods

Factorss that affect the ability to absorb vitamin D from foods and/or produce vitamin D from exposure to sunlight:

  • liver or kidney problems
  • obesity
  • being an elder

More info:
Harvard School of Public Health: Low Vitamin D: What increases the risk?

How can vitamin D deficiency affect mothers?

Recent research has found that vitamin D is vital to many different body processes. Below are just a few examples of the many ways that vitamin D deficiency can affect mothers over time.

  • immune deficiency (sick more frequently, more prone to infection)
  • muscle pain
  • osteomalacia (softening of the bones)
  • osteopenia (low bone mineral density)
  • type 2 diabetes
  • certain types of cancer
  • chronic inflammation (a risk factor in a variety of disease processes)

More info:
Vitamin D Deficiency: Symptoms, Causes, and Health Risks

What can happen if babies do not get enough vitamin D?

Some affects of vitamin D deficiency are:

  • slow growth
  • lethargy
  • irritability
  • predisposition to respiratory infections
  • hypocalcemia (low blood calcium levels)
  • decreased bone mineralization
  • rickets (a softening of bone that causes deformities, found in extreme cases of vitamin D deficiency)
  • increased risk of future disease (such as type 1 diabetes, osteoporosis, certain types of cancer, psoriasis, multiple sclerosis, and rheumatoid arthritis)

Vitamin D plays a vital role in the growth, development, and long term health of your baby. Talk to your health-care provider about your baby’s vitamin D requirements.

More info:
AAP: Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents

How can I prevent vitamin D deficiency during pregnancy and lactation?

Because vitamin D intake during pregnancy affects the baby’s vitamin D stores as well as the mother’s, some experts recommend that the mother gets more than the 400IU of vitamin D3 that is in most prenatal prescriptions (emerging research suggests 4000IU may be necessary to ensure adequate levels of vitamin D), as well as expose themselves to sunlight and eat vitamin D-rich foods. Talk to your health-care provider about what is best for your individual needs.

During lactation, some experts recommend that both mother and baby receive adequate exposure to sunlight and that mother eat foods high in vitamin D. A vitamin D3 supplement is generally recommended for baby and mother, especially if they are at increased risk for vitamin D deficiency.

If you are concerned that you might be deficient or at risk for deficiency, you can ask your health-care provider to evaluate your risk, a process that might include a simple blood test to measure your vitamin D levels.  Your health-care provider can advise you on your vitamin D needs.

Please see the links below for more detailed information and current recommendations for supplementation and the rationale for doing so. You may wish to use this information as a guide when talking to your health-care provider about vitamin D for you and your family.

Vitamin D Recommendations During Pregnancy, Lactation, and Early Infancy

Vitamin D and breastmilk…what’s a babe to do? and My thoughts on the vitamin D controversy

Prevention of Rickets and Vitamin D deficiency in breastfed infants

In this video, researcher Dr. Carol Wagner is interviewed explaining the early findings of her group that studied 400IU of vitamin D vs 4000IU of vitamin D during pregnancy. Here is a recent report of the study: Vitamin D supplementation during pregnancy: double-blind, randomized clinical trial of safety and effectiveness.


What can a blood test tell my health-care provider about my vitamin D status?

A blood test can measure how much of the storage form of vitamin D, calcidiol (25 hydroxy vitamin D– 25-OH-D), is present in your blood.

One group of experts suggests that a reading of above 32 nanograms per milliliter is sufficient. (Hollis, Wagner 2005)  The same group has also reported that levels between 20-32 ng/mL are considered “insufficient,” and under 20 ng/mL is considered “deficient.” Other experts suggest that a reading above 20 ng/mL is sufficient.

More info about the test:
Medline Plus: 25-hydroxy vitamin D test

What are the current supplemental vitamin D recommendations for breastfed infants?

The American Academy of Pediatrics recommends the following:
“A supplement of 400 IU/day of vitamin D should begin within the first few days of life and continue throughout childhood. Any breastfeeding infant, regardless of whether he or she is being supplemented with formula, should be supplemented with 400 IU of vitamin D.”
AAP: Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents

The Canadian Paediatric Society recommends the following:
“Babies who are breastfed should get 400 IU (international units) per day.

Babies in northern communities (north of 55° latitude, which is about the level of Edmonton) or who have other risk factors (such as dark skin) should get 800 IU per day between October and April, when there is less sunlight.”
CPS: Vitamin D

Here is some additional recent research:
Circulating 25-Hydroxyvitamin D Levels in Fully Breastfed Infants on Oral Vitamin D Supplementation

If your health-care provider recommends using a supplement, you may wish to ask about using a preparation that is ONLY vitamin D.  Some experts suggest that mothers avoid “poly” preparations that contain extra vitamins. If your health-care provider recommends a poly version, consider asking why. Sometimes health-care providers recommend them because they are easy to find, or even because they are not aware that other preparations exist, not necessarily because they are best in a particular situation. Single D preparations are now widely available over the counter.

Please ask your health-care provider to show you how to give the correct amount of vitamin supplement to your baby.  When it comes to vitamin D, too much of a good thing may be dangerous, so it makes sense to ensure that you are giving the proper dosage. Never give your baby more vitamin D supplement than your health-care provider recommends.  Note: You can’t overdose on vitamin D from sunlight, but you can get too much vitamin D through supplements.

My baby spits out vitamin D drops my health-care provider recommended. Is there another way to get him to take them?

Some babies spit out vitamin drops, probably due to the taste. If your baby consistently refuses the drops, you could try a different brand or type (check with your health-care provider for recommended brands in your area).  Oil emulsions (“one drop” preparations) often are accepted more readily. You can try putting a single drop of vitamin D onto your nipple just before breastfeeding, or put a drop on your finger and then encourage your baby to suck on it. If your baby continues to refuse the supplement after changing, talk to your health-care provider about other options.

I don’t want to give my baby vitamin drops. Are there alternatives?

One option is to have your 25-OH-D levels tested. If your levels are not adequate, your health-care provider may recommend that you supplement at a dosage that would increase your vitamin D stores and the amount of vitamin D in your milk. Your health-care provider may also recommend adequate sunlight exposure for you and your baby  as well as regular checks of both your and your baby’s 25-OH-D levels. If your levels are adequate, you do not have risk factors for vitamin D deficiency, and you are aware of the risks and benefits of supplementing, a conservative approach to maintain sufficiency might include ensuring adequate sunlight exposure for both mom and baby and including more foods that are high in vitamin D in the mother’s diet. Talk to your health-care provider about your options.

In summary, supplementing with vitamin D is an easy and inexpensive solution for a simple problem (low vitamin D) that can become a complex series of problems if left untreated. Before making a decision about whether or not to supplement, talk to your health-care provider about the risks and benefits, as well as options for ensuring adequate vitamin D for yourself and your family. You and your baby are worth it!

More info that you can read and share with your health-care provider:
Vitamin D Supplementation during Lactation to Support Infant and Mother



Hollis, B. & Wagner C (2005) Normal Serum Vitamin D Levels. New England Journal of Medicine 352:515-516

Wagner, C. (2011) Vitamin D Recommendations During Pregnancy, Lactation and Early Infancy Clinical Lactation 2(1):27-31

First Nations, Inuit and Métis Health Committee, Canadian Paediatric Society (2007) Vitamin D supplementation: Recommendations for Canadian mothers and infants Paediatric Child Health 12(7):583-9

Mora, J.R. et al. (2008) Vitamin effects on the immune system: vitamins A and D take centre stage. Nature Reviews. Immunology. Sep;8(9):685-98.

Changes In Artic Diet Put Inuit At Risk For Rickets. Sara Minogue. The Globe and Mail, June 8th, 2007.

Dietary Supplement Fact Sheet:Vitamin D. ODS National Institutes of Health. 2011

Wagner, C., Howard, C. et al. (2010) Circulating 25-Hydroxyvitamin D Levels in Fully Breastfed Infants on Oral Vitamin D Supplementation International Journal of Endocrinology doi:10.1155/2010/235035

Wagner, C. & Greer, F. (2008) Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents Pediatrics 122(5):1142-1152

Weiler, H., Leslie, W. et al. (2007) Canadian Aboriginal Women Have a Higher Prevalence of Vitamin D Deficiency than Non-Aboriginal Women Despite Similar Dietary Vitamin D Intakes Journal of Nutrition. 137:461-465

Taylor, S. et al. (2008) Vitamin D Supplementation During Lactation to Support Infant and Mother. Journal of American College Nutrition 27(6):690-701

Benson, J., Wilson, A. et al. (2006) Muscle Pain as an Indicator of Vitamin D deficiency in an Urban Australian Aboriginal Population. Medical Journal of Australia 185(2):76-77

(c) Serena Meyer, IBCLC and Jolie Black Bear, IBCLC–All Rights Reserved

updated 7/13/12

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One Response to Vitamin D and Breastfeeding

  1. I love your well researched revamping!!! It is complete and comprehensive.


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