Objective To determine if a single monthly supplement was as effective as a daily maternal supplement in increasing breast milk vitamin D to achieve vitamin D sufficiency in their infants. Patients and Methods Forty mothers with exclusively breastfed infants were randomized to receive oral cholecalciferol (vitamin D3) 5000 IU/d for 28 days or 150,000 IU once. Maternal serum, breast milk, and urine were collected on days 0, 1, 3, 7, 14 and 28; infant serum was obtained on days 0 and 28. Enrollment occurred between January 7 and July 29, 2011. Results In mothers given daily cholecalciferol, concentrations of serum and breast milk cholecalciferol attained steady levels of 18 and 8 ng/mL, respectively, from day 3 through 28. In mothers given the single dose, serum and breast milk cholecalciferol peaked at 160 and 40 ng/mL, respectively at day 1, before rapidly declining. Maternal milk and serum cholecalciferol concentrations were related (r=0.87). Infant mean serum 25(OH)D (±SD) increased from 17±13 to 39±6 ng/mL in the single dose group and from 16±12 to 39±12 ng/mL in the daily dose group (P=.88). All infants achieved serum 25(OH)D concentrations >20 ng/mL). Conclusion Either single dose or daily cholecalciferol supplementation of mothers provided breast milk concentrations that result in vitamin D sufficiency in breastfeeding infants.

Objective To determine the incidence trend of 25-hydroxyvitamin D [25(OH)D] values >50 ng/mL and associated toxicity. Patients and Methods We conducted a retrospective, population-based study in Olmsted County, MN, from January 1, 2002 through December 31, 2011 (10 years) using the Rochester Epidemiology Project. Individuals were eligible if they resided in Olmsted County, MN, during the study period and had a measured 25(OH)D value >50 ng/mL (>125 nmol/L). The date of the first 25(OH)D value >50 ng/mL was considered the index date for incidence determination. Hypercalcemia, the primary vitamin D toxicity, was considered potentially associated with the 25(OH)D concentration if measured within 3 months of the 25(OH)D measurement, and such cases had medical record review. Results Of 20,308 total 25(OH)D measurements, 1714 (8.4%), 123 (0.6%), and 37 (0.2%) unique persons had 25(OH)D values >50, ≥80, and ≥100 ng/mL, respectively. The age- and sex-adjusted incidence of 25(OH)D values >50 ng/mL increased from 9 to 233 per 100,000 person-years from 2002 to 2011 (P<.001), respectively, and was greatest in persons of age ≥65 years (P<.001) and in females (P<.001). Serum 25(OH)D values were not significantly related with serum calcium values or with the risk of hypercalcemia. Medical record review identified four cases (0.2%) where 25(OH)D values >50 ng/mL were associated temporally with hypercalcemia, but only one had clinical toxicity associated with the highest observed 25(OH)D value of 364 ng/mL. Conclusion The incidence of 25(OH)D values >50 ng/mL increased significantly between 2002 and 2011, without a corresponding increase in acute clinical toxicity.

After a 14-day lag, a single high dose of vitamin D led to greater production of 24,25(OH)D, presumably via induction of the 24-hydroxylase enzyme (CYP24A1), relative to the 25(OH)D value than did daily vitamin D supplementation, and this effect persisted for at least 28days after vitamin D administration. A daily dose of vitamin D may have more lasting effectiveness in increasing 25(OH)D with lesser diversion of 25(OH)D to 24,25(OH)D than does larger bolus dosing.

This study compared serum cholecalciferol and 25-hydroxyvitamin D [25(OH)D] concentrations over four weeks in healthy, non-pregnant, non-lactating females aged 18-40 years, who were randomized to oral cholecalciferol 5,000 international units (IU) daily for 28 days or a single dose of 150,000 IU. The study was conducted in Rochester, MN in March and April of 2010. We found no difference in mean 25(OH)D between treatment groups on study day 0 or day 28 (p = 0.14 and 0.28, respectively). The daily group had 11 more days of detectable serum cholecalciferol than the single-dose group (p < 0.001). There was no difference observed in cholecalciferol area under the curve (AUC28) between groups (p = 0.49). However, The single dose group had a significantly greater mean 25(OH)D AUC28 compared with the daily group (p < 0.001).

Daily vitamin D supplementation is recommended for breastfed infants, but alternative methods include enriching breast milk with vitamin D through maternal supplementation or intermittent high-dose vitamin D. We determined maternal preferences for vitamin D supplementation in 140 mothers with exclusively breastfed infants, and 44 who used both breast and formula milk. Only 101 (55%) supplemented their infants with vitamin D. One hundred sixty (88%) preferred supplementing themselves rather than their infants, and 102 (57%) preferred daily to monthly supplementation. Safety was most important in choosing a method of supplementation. Taking maternal preferences into consideration may improve adequate intakes of vitamin D in breastfed infants. INTRODUCTIONV itamin D deficiency has become a global public health concern. Nutritional rickets is the most established consequence, and an increasing incidence of rickets has been observed in developed countries.1,2 In one study up to 18% of US children were vitamin D deficient, and 1% had severe deficiency. 4 Adherence to this recommendation, however, is poor. 5Several studies have explored alternative methods of supplementation. Breast milk can be enriched with vitamin D through daily or intermittent high-dose maternal supplementation to meet infants' vitamin D requirements. 6,7 Alternatively, oral vitamin D, 50,000 IU every 2 months, can be given to healthy infants with routine vaccinations to prevent vitamin D deficiency. 8Little is known about maternal preferences for different methods of vitamin D supplementation. Our aim was to assess maternal practices and preferences for vitamin D supplementation of their infants in primary care. METHODSMothers seeking care with infants for either 2-month or 4-month wellchild visits were surveyed regarding vitamin D supplementation. Eligible mothers were aged 18 years and older, spoke English, and had an infant aged between 6 weeks and 5 months that was receiving primary care at Mayo Clinic in Rochester, Minnesota. Practices included 1 urban site, 2 suburban sites, and 1 rural site.We collected data regarding infant feeding practices, vitamin D supplementation, and maternal preferences for the mode of vitamin D supplementation. Response options included either supplementation of the baby or mother with vitamin D and either daily or monthly high-dose The survey questionnaires were distributed to the mothers in the urban site in October 2013. Questionnaires were mailed to mothers at all 4 sites in November and December 2013. A second mailing was sent to nonrespondents 30 days later. The questionnaires had no patient-identifying information and included instructions not to complete it twice.The Mayo Clinic Institution Review Board approved the study. RESULTSA total of 601 questionnaires were mailed, 438 nonrespondents were sent a second mailing, and 31 completed the survey during well-child visits. In all, 236 mothers completed the survey. We report results for the 140 mothers with exclusively breastfed infants and 44 who use...