Postpartum and Breastfeeding The Science of Nutrition

Does Vitamin D Help With Postpartum?

Dr. Phabillia Afflack

Does Vitamin D Help With Postpartum?

Table of contents

  • Intro
  • Why Vitamin D is Needed Postpartum
  • How Much Vitamin D is Needed Postpartum
  • Vitamin D and Breastfeeding
  • Risks of Deficiency
  • What Is Vitamin D?
  • What Are the Signs of Postpartum Vitamin D Deficiency?
  • Form and Cofactors Matter
  • The Bottom Line

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We know that Vitamin D is crucial in pregnancy for both mama and baby, but the truth is, Vitamin D is just as important (if not more) in postpartum. 

What is Vitamin D

Vitamin D is often referred to as a fat-soluble nutrient, but it is technically a prohormone (a precursor or building block of a hormone). It helps regulate hundreds of genes throughout the body and is critical to the maintenance of healthy bones, muscles, teeth, immune and cardiovascular health, mood, and cognitive function.

Vitamin D is not found abundantly in many foods (a few that do include salmon, sardines, beef liver, and some mushrooms). The body can synthesize Vitamin D from the sun, but a number of factors can limit how much you actually get, including time in the sun, skin cover or sunscreen use, location and season, and skin pigmentation.

Since sources of Vitamin D are limited and amount synthesized from the sun is difficult to measure, Vitamin D supplements are commonly recommended.

Why Vitamin D is Needed Postpartum

Vitamin D remains critical for both mama and baby’s health after baby is born, whether or not mama is breastfeeding.

For mama, Vitamin D continues to provide support for immunity, mood and brain health, bone health, thyroid health, and blood sugar metabolism. For baby, Vitamin D supports immunity and the development and health of bones and teeth.

How Much Vitamin D is Needed Postpartum

As in pregnancy, the amount of Vitamin D that a mama needs can depend on a number of factors, primarily current Vitamin D levels. However, we have some general guidelines assuming that current Vitamin D levels are sufficient. Of course, if you aren’t sure what your levels are, you can request a test from your healthcare provider or order your own to take at home

For baby

Existing research suggests that infants need 400 IU of Vitamin D per day. Infants can get this one of three ways:

  1. Direct supplementation: Infants can be supplemented directly with a Vitamin D3 drop in a bottle of expressed milk or formula, or on mama’s nipple prior to breastfeeding.
  2. Through mamas breast milk. Infants can obtain sufficient Vitamin D through breast milk only if mama is supplementing with at least 6,400 IU of Vitamin D daily herself. Note, this amount was determined through a study that compared maternal Vitamin D supplementation at several different doses to infant Vitamin D supplementation at 400 IU. The study tracked maternal and infant Vitamin D levels at baseline, 4 months and 7 months and concluded that 6,400 IU was sufficient for both mama and baby.
  3. Through infant formula: Infant formula is already fortified with Vitamin D, so infants taking in at least 32 oz. of formula per day do not need additional supplementation. Infants taking in less than this (e.g., consuming a combination of breast milk and formula) should receive supplementation.

For mama

As we discussed in our comprehensive article on Vitamin D deficiency, the RDA for Vitamin D is woefully understated. A growing body of research suggests that an optimal dose of Vitamin D for women who are currently within a healthy range of blood Vitamin D levels is 4,000 IU daily (as compared to the current RDA of 600 IU). 

This recommendation remains the same in the Fourth Trimester and beyond so long as mama is supplementing baby with 400 IU directly. If not, mama needs at least 6,400 IU to cover needs for both herself and baby.

Vitamin D and Breastfeeding

It’s important to know that the amount of Vitamin D in breastmilk is directly related to the amount of Vitamin D that mama obtains through food, sunlight, and supplements. If mama is not getting enough herself, both she and baby will be deficient. 

As mentioned previously, breastfeeding mamas have the option to supplement baby directly or increase their own intake to cover the needs of both herself and baby. Many women find it easier to only have to remember one supplement daily and also find it more reassuring to know that intake is somewhat more predictable through breast milk as it can be unclear how much Vitamin D baby actually gets if they tend to spit up after eating, or don’t always finish a bottle of expressed milk. 

In addition, when baby gets Vitamin D through breast milk, he or she will also get Vitamin K2 through breast milk (assuming mama supplements with a high quality Vitamin D3/K2). Most infant supplements include only Vitamin D, but K2 helps support the effectiveness of Vitamin D’s role in bone health, and one study found that even babies who receive a Vitamin K shot at birth had no detectable levels of Vitamin K at 4 weeks of age.

Risks of Deficiency

Unfortunately, the message to parents about infants’ need for Vitamin D is often missed, late, or misunderstood by either the pediatrician or the parent. Given the importance of Vitamin D, this recommendation should be a priority for physicians to communicate, and for parents to follow through consistently. Sadly, research shows that only 19% of infants end up supplemented with Vitamin D. The result is both mamas and babies finding themselves deficient in Vitamin D, which can have a number of downstream effects:

For mama 

Critical to the postpartum period, insufficient Vitamin D levels have been linked to higher incidence of Perinatal Mood and Anxiety Disorders (PMAD). In addition, adequate Vitamin D status is essential to the maintenance of so many other aspects of health, including immune function, bone health, cardiovascular health, brain health, and insulin regulation. A disruption in any of these systems can have a significant impact on mama’s health in both the short term and long term.

For baby

Insufficient Vitamin D levels in infancy can lead to major and irreversible problems, like rickets, a condition of extremely weak and brittle bones, as well as dental enamel defects, increased rates of cavities, lower bone density, and higher rates of fractures.

What are the signs of postpartum vitamin d deficiency?

So how do you know if you aren’t getting enough Vitamin D? Unfortunately, many women experience few symptoms, or the symptoms they experience can be easily explained by other life circumstances (like having a newborn). Fortunately, Vitamin D testing is relatively easy and affordable. We suggest requesting a test from your practitioner during and after pregnancy. If testing isn’t available through your practitioner, you can order an at home test.

Postpartum Vitamin D deficiency symptoms can include:

  • Fatigue
  • Bone loss
  • Muscle weakness or aches
  • Mood changes
  • Poor wound healing
  • Getting sick often
  • Hair loss

Form and Cofactors Matter

We’ve discussed the benefits of Vitamin D3 over D2 previously and include Vitamin D3 in our Prenatal Multi formulas for optimal absorption. In addition, we pair Vitamin D3 with Vitamin K2 (the more absorbable form of Vitamin K). We do this to support optimal bone and heart health, because the interaction between Vitamin D, Vitamin K, and Calcium matters.

While Vitamin D helps your intestines efficiently absorb calcium, Vitamin K2 helps direct Calcium into your bones. This ensures that the Calcium you consume is used to strengthen bones (boosting bone health) and does not end up lining the walls of your arteries (damaging cardiovascular health). Yes, this means that even if you consume plenty of Calcium, it will not be properly absorbed without the help of Vitamins D3 and K2.

The Bottom Line

The importance of Vitamin D to mama and baby is significantly understated. But just because Vitamin D doesn’t get much attention during the Fourth Trimester and beyond doesn’t mean it isn’t absolutely essential to mama and baby’s health. Don’t let the lack of attention mislead you to skip out on proper supplementation, because you and your baby deserve the best start together!

Our Prenatal Multi can help you and baby maintain optimal Vitamin D levels with a supportive dose of 4,000 IU, and our Prenatal Vitamin D contains 2,000 IU of additional Vitamin D to layer on top for times of additional need like while breastfeeding.

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Dr. Phabillia Afflack, MD

Dr. Phabby has over 20 years of experience in obstetrics, gynecology, and family planning. She’s a Fellow of the American College of Obstetrics and Gynecology and a board-certified OBGYN. Dr. Phabby has a passion for Holistic Medicine and Holistic Obstetrics and Gynecology. She advocates for a collaborative approach to care, a true patient-centered model, that takes into account one’s mind, body, and spirit.