Vitamin D Supplementation for Breastfed Infants

Breastmilk is touted as "nature's perfect food."  It should contain everything that a growing infant should need for at least the first six months of life.  Major organizations from the American Academy of Pediatrics to the World Health Organization recommend exclusive breastfeeding for the first six months of life.  Exclusive breastfeeding means feeding the infant only breastmilk and no other solids or liquids.  If breastmilk is "perfect," why then do we need to give breastfed infants vitamin D supplementation?

According to the Centers of Disease Control and Prevention (CDC), "Breast milk alone does not provide infants with an adequate intake of vitamin D. Most breastfed infants are able to synthesize additional vitamin D through routine sunlight exposure. However, published reports of cases of vitamin D deficiency rickets among breastfed infants in the United States caused researchers to take another look at whether all breastfed infants were getting adequate vitamin D."  "Vitamin D deficiency rickets among breastfed infants is rare, but it can occur if an infant does not receive additional vitamin D from a vitamin supplement or from adequate exposure to sunlight. A number of factors decrease the amount of vitamin D a person will synthesize from sunlight. These factors include:
- Living at high latitudes (closer to the polar regions), particularly during winter months
- Air quality conditions: high levels of air pollution
- Weather conditions: dense cloud covering
- The degree to which clothing covers the skin
- Use of sunscreen
- Skin pigmentation: darker skin types
- Furthermore, there exists a major public health effort to decrease the risk of skin cancer by encouraging people to limit their sunlight exposure"

The American Academy of Pediatrics (AAP), recommends "that all infants and children, including adolescents, have a minimum daily intake of 400 IU of vitamin D beginning soon after birth."  The "guidelines for vitamin D intake for healthy infants, children, and adolescents are based on evidence from new clinical trials and the historical precedence of safely giving 400 IU of vitamin D per day in the pediatric and adolescent population. New evidence supports a potential role for vitamin D in maintaining innate immunity and preventing diseases such as diabetes and cancer. The new data may eventually refine what constitutes vitamin D sufficiency or deficiency."

"There are 2 forms of vitamin D: D2 (ergocalciferol, synthesized by plants) and D3 (cholecalciferol, synthesized by mammals). The main source of vitamin D for humans is vitamin D3 through its synthesis in the skin" when exposed to ultraviolet light.  "Historically, the main source of vitamin D has been via synthesis in the skin from cholesterol after exposure to UV-B light. Full-body exposure during summer months for 10 to 15 minutes in an adult with lighter pigmentation will generate between 10000 and 20000 IU of vitamin D3 within 24 hours; individuals with darker pigmentation require 5 to 10 times more exposure to generate similar amounts of vitamin D3."  Vitamin D3 which is derived from fish "has greater efficacy in raising" vitamin D levels.  It is the supplement of choice over vitamin D2.

"In a lactating mother supplemented with 400 IU/day of vitamin D, the vitamin D content of her milk ranges from <25 to 78 IU/L."  Even if a mother takes a vitamin D supplement and her infant drinks a liter of breastmilk a day, this is far less than the 400IU recommended daily for infants.   For a woman to produce the recommended amount of vitamin D in her breastmilk, she will have to consume 6400 IU/day of vitamin D supplements.  "Although vitamin D concentrations can be increased in milk of lactating women by using large vitamin D supplements, such high-dose supplementation studies in lactating women must be validated and demonstrated to be safe in larger, more representative populations of women across the United States. Recommendations to universally supplement breastfeeding mothers with high-dose vitamin D cannot be made at this time. Therefore, supplements given to the infant are necessary."

Vitamin D supplementation is recommended because "in adults, new evidence suggests that vitamin D plays a vital role in maintaining innate immunity and has been implicated in the prevention of certain disease states including infection, autoimmune diseases (multiple sclerosis, rheumatoid arthritis), some forms of cancer (breast, ovarian, colorectal, prostate), and type 2 diabetes mellitus.  Results from prospective observational studies also suggest that vitamin D supplements in infancy and early childhood may decrease the incidence of type 1 diabetes mellitus."

Despite the recommendations by the AAP, a study published in the journal Pediatrics, titled, "Adherence to Vitamin D Recommendations Among US Infants," found that "most US infants are not consuming adequate amounts of vitamin D according to the 2008 AAP recommendation. Pediatricians and health care providers should encourage parents of infants who are either breastfed or consuming <1 L/day of infant formula to give their infants an oral vitamin D supplement."  I don't find this particularly surprising since many message boards that I have been reading have threads full of mothers saying that their Pediatricians have told them that it "wasn't necessary."

I plan on supplementing my baby with vitamin D especially since I will not be exposing him to much sunlight during his first six months of life.  I remember that with my first baby, it was difficult in the beginning to get him to take his vitamin drop and I wasn't always that consistent with it.  After researching this topic, I am going to have to make sure that I am more diligent with the vitamins and also be more diligent with myself getting enough calcium and vitamin D.

Are You Getting Enough Calcium and Vitamin D?

Calcium and Vitamin D are vitamins that we have been told will prevent osteoporosis when we are older.  However, an "interesting draft recommendation statement" recently made headlines when the U.S. Preventative Task Force (USPSTF) recommended that "evidence is lacking regarding the benefit of daily supplementation with >400 IU of vitamin D3 and 1,000 mg of calcium for the primary prevention of osteoporotic fractures, and the balance of benefits and harms cannot be determined.  The USPSTF concludes with moderate certainty that daily supplementation with ≤400 IU of vitamin D3 and 1,000 mg of calcium carbonate has no net benefit for the primary prevention of osteoporotic fractures."  They based this recommendation due to the lack of studies showing the benefits of calcium supplementation in healthy post-menopausal women in preventing osteoporotic fractures.  There were, however, "adequate evidence that supplementation with ≤400 IU of vitamin D3 and 1,000 mg of calcium carbonate increases the incidence of renal stones. The USPSTF assessed the magnitude of this harm as small."

With this "draft recommendation statement," the USPSTF could not recommend 1,000mg calcium and ≤400 IU of vitamin D supplementation in healthy post-menopausal women due to the lack of evidence showing a benefit in preventing fractures in comparison to the "adequate evidence" that supplementation can increase the incidence of renal (kidney) stones.  This is a "draft recommendation statement" and not a final recommendation and is available for public comment until July 10, 2012.

I think many people are applying this recommendation to groups other than post-menopausal women.  As a pregnant and soon-to-be lactating woman, it is still recommended that I take 1,000mg of calcium and 600 IU of vitamin D daily.  All 1,000mg of calcium should not be taken at one time.  "The percentage of calcium absorbed depends on the total amount of elemental calcium consumed at one time; as the amount increases, the percentage absorption decreases. Absorption is highest in doses ≤500 mg [1]. So, for example, one who takes 1,000 mg/day of calcium from supplements might split the dose and take 500 mg at two separate times during the day."  Vitamin D supplementation is needed along with calcium because "Vitamin D promotes calcium absorption in the gut and maintains adequate serum calcium and phosphate concentrations to enable normal mineralization of bone and to prevent hypocalcemic tetany. It is also needed for bone growth and bone remodeling by osteoblasts and osteoclasts.  Together with calcium, vitamin D also helps protect older adults from osteoporosis."

Unless new information becomes available regarding pregnant and lactating women, I will continue to take my calcium supplements and/or eat my calcium rich foods (like broccoli).  I think maintaining an adequate intake of calcium and vitamin D now will prevent the development of osteoporosis in the future.