The Epidemic of Vitamin D Deficiency

Deborah Goldstein, Journal of Pediatric Nursing, Volume 24, Issue 4, August 2009, Pages 345-346.

Vitamin D deficiency is of epidemic proportions and is being identified across the lifespan and worldwide¹.There are reports of vitamin D deficiency in 36% of healthy young adults, 80% of healthy White infants, and 52% of adolescent African American and Hispanic children^2-3. The emergence of vitamin D deficiency can be attributed to multiple factors. The modern-day practice of avoiding the sun because of fear of skin cancer and the use of sun block contribute to the rise of vitamin D deficiency¹. In many countries where sunshine is ample, cultural practices requiring women to be covered with clothing contribute to lack of vitamin D^1-3. A biologic factor that decreases bioavailability is body fat content, since vitamin D is stored in body fat and unavailable for use. Studies show that body mass index and body fat content have an inverse relation to serum levels of 25 hydroxyvitamin D^2-3. The concurrent epidemic of obesity adds to the epidemic proportions of vitamin D deficiency. Another factor contributing to the increase in prevalence of vitamin D deficiency is the lack of knowledge that human breast milk is deficient in vitamin D¹. Breast milk is touted as providing all necessary nutrients, and often, mothers are not counseled about their infants' need for sunshine and/or vitamin D supplementation. A recent study showed that at 280 days of age, 10% of breast-fed infants were vitamin D-deficient (25 hydroxyvitamin D <11 ng/ml). Deficiency was significantly more prevalent among dark-skinned infants and during winter and occurred exclusively in unsupplemented infants. During winter, 78% of unsupplemented infants were vitamin D-deficient⁴. Human breast milk has insufficient vitamin D at approximately 20 IU/L, and many mothers themselves are vitamin D-deficient, impacting fetal growth and development as well as neonatal health¹.

References

1. M.F. Holick, Vitamin D deficiency, New England Journal of Medicine 357 (2007), pp. 266-281.
2. M.F. Holick, High prevalence of vitamin D inadequacy and implications for health, Mayo Clinic Proceedings 81 (2006), pp. 353-373.
3. M.F. Holick, Resurrection of vitamin D deficiency and rickets, Journal of Clinical Investigations 116 (2006), pp. 2062-2072.
4. Ziegler et al., 2006 E.E. Ziegler, B.W. Hollis, S.E. Nelson and J.M. Jeter, Vitamin D deficiency in breastfed infants in Iowa, Pediatrics 118 (2006), pp. 603-610.