Vitamin D and the Breastfed Infant

Association between Vitamin D Levels, Puberty Timing, and Age at Menarche

Pubertal development represents the process of physical maturation where an adolescent reaches sexual maturity and attains reproductive function. The effects of vitamin D are mainly mediated by the vitamin D receptor (VDR), which is expressed in almost all body cells, including the ovary and human pituitary gland and animal hypothalamus. Thus, vitamin D has gained great interest as pathogenic factor of pubertal disorders and fertility. This narrative review aimed to provide a broad overview of the available literature regarding the association between vitamin D levels, puberty timing, and age at menarche. A review of the data on the involvement of micronutrient deficiency, as a modifiable cause of pubertal disorders, is important for the prediction and prevention of deficiencies as well as for fertility protection and should be considered a public health priority. Reported data support that vitamin D is a regulator of neuroendocrine and ovarian physiology and, more in detail, a deficiency of vitamin D is involved in altered pubertal timing. Considering the long-term consequences of early pubertal development and early menarche, the detection of modifiable causes is crucial in preventive strategies. Future studies in humans and with an increased scale are needed to elucidate the vitamin D role in sexual maturation and puberty development.

Influences on Skeletal Health and Bone Mineralization in Children

Bone is in its most active formation phase of mineralization in the pediatric and adolescent population. Peak bone mass is achieved around the late teens to early 20s. Deficient bone mineralization and decreased peak bone mass acquisition predispose an individual to childhood fractures or lifelong fracture risk. Adolescent fragility or stress fractures should prompt a secondary evaluation for the causes of a low bone mineral content, the root of a fracture. The purpose of this article is to review published literature that discusses the risk factors associated with a decreased bone mineral content in children from birth to the age of peak bone mass. The article also includes a public health planning model for pediatric osteoporosis.

Vitamin D and health - The missing vitamin in humans

Severe vitamin D deficiency may cause rickets in infants or children and osteomalacia in adults, though it is now uncommon in developed countries. However, subclinical vitamin D deficiency is more prevalent, and it is associated with osteoporosis and higher incidence of falls or fractures. It was reported that 96% children with rickets were breastfed, since breast milk contains inadequate vitamin D. The American Academy of Pediatrics 2008 recommended infants who were exclusively or partially breastfed required 400 international units vitamin D daily from the first few days of life. Furthermore, since vitamin D receptors are present all over the body, insufficient vitamin D status may correlate with several extra-skeletal effects, such as pregnancy-related complications and immune dysfunction. This paper discusses the researches regarding system-based vitamin D effects, the possible risk factors leading to vitamin D deficiency, and the recommendations of vitamin D requirements. It is well-known that vitamin D can be obtained by sun exposure or limited natural dietary sources. The American Academy of Dermatology declared ultraviolet radiation to be a known skin carcinogen, so it may not be safe or efficient to obtain vitamin D via sun exposure or other artificial sources. Therefore, many pediatricians and physicians recommend appropriate vitamin D supplementation to achieve optimal plasma concentration. Trials assessing the effects of vitamin D repletion and establishing its optimum serum level are ongoing. Medical advice for vitamin D supplementation should be individualized accordingly.

Maternal and Cord Blood Vitamin D Status and Anthropometric Measurements in Term Newborns at Birth

INTRODUCTION

Vitamin D deficiency in pregnant women may result in reduced neonatal development due to the fact that systemic vitamin D status during fetal life depends on maternal concentrations. Some authors reported significant differences in neonatal anthropometric measurements depending on maternal vitamin D concentrations.

OBJECTIVE

The aim of this study is to evaluate the relationship between maternal and cord blood concentrations of vitamin D and neonatal anthropometric measurements at birth.

MATERIALS AND METHODS

This study included 94 pregnant women, at term, who delivered at the Department of Obstetrics, Women's Diseases and Gynecological Oncology, Medical University of Warsaw. Total serum 25(OH)D concentration was measured in mother-child pairs, and newborn anthropometric data were collected. A multiple regression analysis was used for statistical analysis.

RESULTS

No relationship between maternal and neonatal cord blood vitamin D concentrations vs. neonatal weight, length, head, and chest circumference at birth was found (p > 0.05). Severe vitamin D deficiency (<10 ng/ml) was detected in 10.6%, deficiency (10-20 ng/ml) in 39.4%, insufficiency (20-30 ng/ml) in 39.4%, and optimal vitamin D concentration (>30 ng/ml) only in 10.6% of the pregnant women. Cord blood vitamin D deficiency (<20 ng/ml) was found in 28.7% of the neonates.

CONCLUSION

No differences between neonatal anthropometric measurements of infants born to mothers with normal and deficient vitamin D concentrations were found.

Micronutrient Deficiencies among Breastfeeding Infants in Tanzania

Infant mortality accounts for the majority of child deaths in Tanzania, and malnutrition is an important underlying cause. The objectives of this cross-sectional study were to describe the micronutrient status of infants in Tanzania and assess predictors of infant micronutrient deficiency. We analyzed serum vitamin D, vitamin B12, folate, and ferritin levels from 446 infants at two weeks of age, 408 infants at three months of age, and 427 mothers three months post-partum. We used log-Poisson regression to estimate relative risk of being deficient in vitamin D and vitamin B12 for infants in each age group. The prevalence of vitamin D and vitamin B12 deficiency decreased from 60% and 30% at two weeks to 9% and 13% at three months respectively. Yet, the prevalence of insufficiency at three months was 49% for vitamin D and 17% for vitamin B12. Predictors of infant vitamin D deficiency were low birthweight, urban residence, maternal education, and maternal vitamin D status. Maternal vitamin B12 status was the main predictor for infant vitamin B12 deficiency. The majority of infants had sufficient levels of folate or ferritin. Further research is necessary to examine the potential benefits of improving infants’ nutritional status through vitamin D and B12 supplements.

Safety and Efficacy of Stosstherapy in Nutritional Rickets

OBJECTIVE

Stosstherapy has been used since early 19^th century for treating nutritional rickets. However, there are no clear cut guidelines for the biochemical monitoring of this treatment. Repeated blood tests at short intervals increase the cost of therapy and noncompliance.

METHODS

A prospective study was conducted on 191 cases of nutritional rickets below 10 years of age to evaluate the effectivity of stosstherapy. All cases were treated with a single intramuscular injection of vitamin D (600.000 IU) along with oral calcium (50 mg/kg) and vitamin D (400 IU per day) until radiological resolution. Dietary modifications and adequate sunlight exposure were also recommended.

RESULTS

The mean age of presentation was 2 years 9 months. Mean sunlight exposure was 17 minutes/week with 90% having low sunlight exposure (<30 minutes/week). Prolonged breast feeding (>6 months) was found in 93.7% of the cases. With treatment, the clinical features started resolving by 1 month with complete resolution of most of the features over a period of 1 year. By 6 months, all the study subjects had complete radiological resolution. Serum levels of calcium and alkaline phosphatase (ALP) were restored by 6 months in most cases while phosphate and vitamin D levels normalized by 6 weeks.

CONCLUSION

Stosstherapy is a safe, cheap and effective method of treating nutritional rickets. Biochemical tests at initial presentation followed by vitamin D assay at 6 weeks and calcium, phosphate and ALP assays at 6 months is recommended in the monitoring of these patients. For regular monitoring, only ALP assay is recommended, provided one abstains from repeat injection of vitamin D based on high ALP levels.

Relationship between newborn craniotabes and vitamin D status

OBJECTIVE

In recent studies, vitamin D deficiency during pregnancy and early infancy has been reported to predispose children to many chronic diseases, except those of the skeletal system. The aim of this study was to investigate whether craniotabes in otherwise healthy newborns is physiological, its relationship to vitamin D deficiency and whether or not it requires treatment.

METHODS

A total of 150 healthy newborns with a weight of over 2000 g were included. Newborns were divided into two groups during postnatal discharge (1-3.'s day): those with and without craniotabes. The 25-hydroxy (OH) vitamin D levels of the newborns' mothers were measured, and all infants were re-evaluated for craniotabes, as well as tested to determine levels of serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), parathyroid hormone (PTH) and 25(OH) vitamin D, urine calcium and creatinine.

RESULTS

Craniotabes was present in 45 (30%) of newborns enrolled in the study. Craniotabes of the newborns born during the winter months was significantly higher. PTH level was significantly higher in 1-month-old newborns with craniotabes than those without craniotabes. No relationship was observed between diet and craniotabes, but in exclusively breastfed infants, vitamin D level was statistically significantly lower. No statistically significant difference was found in the occurrence of craniotabes in newborns with or without vitamin D support.

CONCLUSION

The relationship between newborn craniotabes and maternal vitamin D deficiency is not clear. However, the present study illustrates that maternal vitamin D deficiency is still a major problem. Therefore, measures to prevent maternal vitamin D deficiency should be strengthened.

Iron and vitamin D status in breastfed infants and their mothers

Purpose

We assessed the relationships between iron and vitamin D statuses in breastfed infants and their mothers and evaluated the determinants of iron and vitamin D deficiencies in breastfed infants.

Methods

Seventy breastfed infants aged 4-24 months and their mothers participated in this study from February 2012 to May 2013. Complete blood counts, total iron binding capacity, and levels of C-reactive protein, iron, ferritin, calcium, phosphate, alkaline phosphatase, and 25-hydroxyvitamin D (25(OH)D) in infants and their mothers were measured.

Results

A history of maternal prepregnancy anemia was associated with lower ferritin and 25(OH)D levels in both infants and their mothers. The 25(OH)D level of infants correlated with maternal 25(OH) D levels. The independent risk factors for iron deficiency in breastfed infants were the duration of breastfeeding (odds ratio [OR], 6.54; 95% confidence interval [CI], 1.09-39.2; P=0.04) and infant body weight (OR, 2.65; 95% CI, 1.07-6.56; P=0.04). The determinants for vitamin D deficiency were the infant's age (OR, 0.15; 95% CI, 0.02-0.97; P=0.046) and maternal 25(OH)D level (OR, 0.74; 95% CI, 0.59-0.92; P=0.01).

Conclusion

A maternal history of prepregnancy anemia requiring iron therapy was associated with lower current ferritin and 25(OH)D levels in both infants and their mothers. Therefore, physicians should monitor not only iron but also vitamin D levels in infants who are breastfed by mothers who had prepregnancy anemia.

Determinants of 25-Hydroxyvitamin D Concentrations in Infants and Toddlers

BACKGROUND

Resurgence of rickets and recognition of excessive prevalence of hypovitaminosis D among all age groups in the western hemisphere have refocused attention on vitamin D nutrition.

OBJECTIVE

To examine the prevalence of hypovitaminosis D [25-hydroxyvitamin D [25(OH)D] <30ng/mL] and characterize the determinants of 25(OH)D concentrations in 8- to 24-month-old healthy infants and toddlers living in Pittsburgh, Pennsylvania.

METHODS

Serum 25(OH)D concentrations were measured and dietary intake of vitamin D, mode of feeding, summertime sun exposure characteristics, and skin color (sun-reactive skin type and melanin index) were assessed.

RESULTS

A total of 111 healthy 8- to 24-month-old children (mean age [±SD] 14.4 [±3.5] months; male, 51%; black, 67%) were studied. Serum 25(OH)D concentration was <30 ng/mL in 16% (n=18) of the children. Median (interquartile) 25(OH)D concentration was lower in children who were ≥ 13 months vs. <13 months of age [35 (31, 40.5) vs. 40 (35.8, 44.3) ng/mL, p=0.013]; with sun-reactive skin type IV and V vs. I, II, and III [36 (31, 41) vs. 44 (36.5, 48.5) ng/mL, p=0.001]; and examined during fall/winter vs. spring/summer [35.5 (32.5, 38.5) vs. 39 (32.5, 44) ng/mL, p=0.05]. Age and skin type were significant independent predictors of 25(OH)D.

CONCLUSIONS

Concentrations of 25(OH)D tend to be lower in infants and toddlers during fall/winter, and in children who are older (≥13 months vs. <13 months of age) and have darker skin tone. Benefits of enhancement of 25(OH)D concentrations during fall/winter and in children with higher sun-reactive skin type need further exploration.

Prevalence and risk factors for vitamin D deficiency among Tanzanian HIV-exposed uninfected infants

Vitamin D is essential for bone development and may also play an integral role in control of intracellular pathogens. Serum 25-hydroxyvitamin D levels were assessed at 6 months of age for 191 HIV-exposed uninfected infants enrolled in a trial of multivitamins (not including vitamin D) in Tanzania. A total of 66 infants (34.6%) were classified as vitamin D deficient (<20 ng/ml), 93 (48.7%) as vitamin D insufficient (20-30 ng/ml) and 32 (16.8%) as vitamin D sufficient (≥30 ng/ml). Independent risk factors for vitamin D deficiency were sampling during the rainy season and infant wasting. Infant breastfeeding, maternal CD4 T-cell count, maternal wasting status and maternal receipt of antiretroviral therapy were not associated with vitamin D deficiency. Low levels of vitamin D were highly prevalent among HIV-exposed uninfected infants in Tanzania, and longitudinal studies and clinical trials of supplementation are needed to assess the impact on child health.

Vitamin D deficiency in infants aged 1 to 6 months

Purpose

The aim of this study was to recognize the state of vitamin D among healthy infants aged 1 to 6 months in South Korea, and also to identify the risk factors affecting the level of vitamin D.

Methods

A total of 117 infants were enrolled in this study for 12 months, from March 1, 2011 to February 29, 2012. Serum levels of 25-hydroxyvitamin D (25[OH]D), calcium, phosphorus, and alkaline phosphatase were measured and data including birth weight, body weight, sex, feeding pattern, delivery mode, siblings and maternal age and occupation were collected. Data was mainly analyzed with independent t-test model.

Results

We determined that the prevalence of vitamin D deficiency (serum 25[OH]D<20 ng/mL [50 mmol/L]) was 48.7% in the population investigated. Particularly in breastfed infants, the prevalence of vitamin D deficiency was strikingly high (90.4%). The mean serum level of 25(OH)D in breastfed infants was lower than that of formula fed infants (9.35 ng/mL vs. 28.79 ng/mL). Also female infants showed lower mean serum level of 25(OH)D than male. Mean serum values of calcium and phosphorus had positive correlation with vitamin D state (P<0.001).

Conclusion

Vitamin D deficiency was found to be very common in infants aged 1 to 6 months in South Korea, and breast feeding was the most critical risk factor of vitamin D deficiency. Therefore we suggest to start vitamin D supplementation in South Korea, as soon as possible, to all infants, including breastfed and female infants.

Vitamin D status of exclusively breastfed 4-month-old infants supplemented during different seasons

OBJECTIVE

To examine the vitamin D status of 4-month-old exclusively breastfed infants supplemented with 400 IU daily of vitamin D and to determine whether there was any seasonal variation in serum 25-hydroxyvitamin D (25(OH)D) levels of infants.

METHODS

In this cross-sectional study, serum calcium, phosphorus, alkaline phosphatase, parathyroid hormone, and 25(OH)D levels of 143 exclusively breastfed 4-month-old infants supplemented daily with 400 IU of vitamin D were measured in a temperate latitude, Izmir, Turkey, between May 2008 and April 2009. A questionnaire on demographic characteristics of infants and mothers, vitamin D supplementation of infants after birth, mothers' multivitamin supplementation, dressing habits, and consumption of dairy products during pregnancy was used.

RESULTS

Vitamin D deficiency (≤ 50 nmol/L) and insufficiency (51-74 nmol/L) were determined in 40 (28%) and 55 (38.5%) infants, respectively. During winter days, serum 25(OH)D levels were <20 ng/mL in 45.4% of infants and <10 ng/mL in 10.6% of infants. Season of blood sampling, compliance of vitamin D supplementation, maternal education level, and consumption of dairy products were highly predictive of serum 25(OH)D levels in multiple linear regression analysis (P < .05). The use of the Pearson correlation test found a statistically significant negative correlation between 25(OH)D and parathyroid hormone levels (r = -0.419, P < .001).

CONCLUSIONS

Despite supplementation with 400 IU of vitamin D daily, the rate of vitamin D deficiency was worryingly high in 4-month-old exclusively breastfed infants living in Izmir, Turkey. So, additional studies are needed to clarify optimal amount of vitamin D supplementation to the infants, especially during winter days.

Vitamin D deficiency in pregnant women and their neonates in spring time in western Turkey

Although Turkey is located in a sunny region, vitamin D deficiency is still a serious health problem in pregnant women and their infants, especially among the low socio-economic status Turkish population. This study was carried out in order to measure serum 25-hydroxyvitamin D3 [25(OH)D] concentrations of the pregnant women in the last trimester and in their neonates at delivery and to determine the factors associated with maternal serum 25(OH)D concentrations. Among the patients visiting the Ege Obstetrics and Gynecology Hospital in the period March to May 2008, 258 healthy pregnant women ≥37 weeks of gestation were included in this study. The information on different characteristics such as the number of pregnancies and births, nutritional status, vitamin and mineral support during gestation, educational status, clothing style and the economic level of the family was collected from women. Blood samples from the mothers and umbilical cord of the newborns were taken to measure 25(OH)D. The mean 25(OH)D concentrations of the mothers and their infants were 11.5 ± 5.4 ng/mL and 11.5 ± 6.8 ng/mL, respectively. We found a strong positive correlation between maternal serum and umbilical cord blood 25(OH)D concentrations (r = 0.651, P < 0.001). The concentration of 25(OH)D was ≤20 ng/mL in 233 mothers (90.3%) and ≤10 ng/mL in 130 mothers (50.4%). Maternal serum 25(OH)D concentrations related strongly to factors such as uncovered dressing style, sufficient consumption of dairy products and multivitamin use during gestation (P < 0.05). About half (52.7%) of these women had a covered dressing style. 25(OH)D concentrations of these covered dressing mothers and their infants were 9.7 ± 5.1 ng/mL and 9.7 ± 5.6 ng/mL, respectively, which were significantly lower compared with those of uncovered mothers and their babies (P < 0.001). This study showed that, despite a sunny environment, vitamin D deficiency and insufficiency are highly prevalent among the mothers and their neonates. This is generally due to the life style and nutritional status of the mothers. These findings suggest that much more effective vitamin D prophylaxis programmes should be implemented for pregnant women as well as for their babies.

Maternal supplementation for prevention and treatment of vitamin D deficiency in exclusively breastfed infants

Current research links newborn and infant vitamin D deficiency with various clinical outcomes, including rickets, failure to thrive, type 1 diabetes, and other immune-related diseases. Breastfed infants are often at a greater risk of developing deficiency due to their mothers' low vitamin D status. Human milk reflects the vitamin D status of the mother and often contains inadequate levels of 25-hydroxyvitamin D for infant nutrition. In 2008 the American Academy of Pediatrics (AAP) recommended 400 IU of vitamin D supplementation of all infants. However, research has indicated low levels of compliance of vitamin D supplementation of breastfed infants and a high incidence of vitamin D deficiency in the United States. Many breastfeeding advocates believe that the AAP's recommendations undermine breastfeeding, implying that human milk is inadequate for infant nutrition. Lactating mothers are also reluctant to add any supplements to their breastmilk. The literature review will examine the effectiveness and safety of maternal vitamin D supplementation for prevention and/or treatment of vitamin D deficiency in breastfed infants and lactating mothers. This method of prevention and intervention provides pediatric providers and certified lactation consultants with an alternative approach for education, counseling, promotion of breastfeeding, and treatment to improve maternal and infant health.

A treatment trial of vitamin D supplementation in breast-fed infants: universal supplementation is not necessary for rickets prevention in Southern Louisiana

This study was conducted to determine if vitamin D supplementation is required to prevent rickets in breast-fed infants. Breast-feeding rates are increasing, and there are concerns about whether the vitamin D content of breast milk is sufficient. There are a few treatment trials of vitamin D supplementation in breast-fed infants; these were conducted in northern climates. The authors therefore performed a prospective clinical trial comparing vitamin D supplementation with placebo as control in southern Louisiana. Blood samples and questionnaires were collected at birth, 2, 4, and 6 months of age. There were no cases of rickets observed, and no differences in alkaline phosphatase levels between groups. Thus, there was no evidence that vitamin D supplementation reduced rickets risk in the authors' study population. This suggests that the current recommendations for universal vitamin D supplementation of breast-fed infants throughout the United States may need to be revised.

Vitamin D deficiency in children and its management: review of current knowledge and recommendations

Given the recent spate of reports of vitamin D deficiency, there is a need to reexamine our understanding of natural and other sources of vitamin D, as well as mechanisms whereby vitamin D synthesis and intake can be optimized. This state-of-the-art report from the Drug and Therapeutics Committee of the Lawson Wilkins Pediatric Endocrine Society was aimed to perform this task and also reviews recommendations for sun exposure and vitamin D intake and possible caveats associated with these recommendations.

Shedding light on hypovitaminosis D and rickets

The recent resurgence of the ancient disease of vitamin D deficiency rickets and the widespread presence of hypovitaminosis D across the age spectrum pose significant challenges for today's clinicians. Furthermore, new research into previously unsuspected actions of vitamin D in multiple cell systems offer the possibility that vitamin D will play an increasingly important role in our understanding of a wide variety of disease states.