This article summarizes the new 2011 report on dietary requirements for calcium and vitamin D from the Institute of Medicine (IOM). An IOM Committee charged with determining the population needs for ...these nutrients in North America conducted a comprehensive review of the evidence for both skeletal and extraskeletal outcomes. The Committee concluded that available scientific evidence supports a key role of calcium and vitamin D in skeletal health, consistent with a cause-and-effect relationship and providing a sound basis for determination of intake requirements. For extraskeletal outcomes, including cancer, cardiovascular disease, diabetes, and autoimmune disorders, the evidence was inconsistent, inconclusive as to causality, and insufficient to inform nutritional requirements. Randomized clinical trial evidence for extraskeletal outcomes was limited and generally uninformative. Based on bone health, Recommended Dietary Allowances (RDAs; covering requirements of ≥97.5% of the population) for calcium range from 700 to 1300 mg/d for life-stage groups at least 1 yr of age. For vitamin D, RDAs of 600 IU/d for ages 1–70 yr and 800 IU/d for ages 71 yr and older, corresponding to a serum 25-hydroxyvitamin D level of at least 20 ng/ml (50 nmol/liter), meet the requirements of at least 97.5% of the population. RDAs for vitamin D were derived based on conditions of minimal sun exposure due to wide variability in vitamin D synthesis from ultraviolet light and the risks of skin cancer. Higher values were not consistently associated with greater benefit, and for some outcomes U-shaped associations were observed, with risks at both low and high levels. The Committee concluded that the prevalence of vitamin D inadequacy in North America has been overestimated. Urgent research and clinical priorities were identified, including reassessment of laboratory ranges for 25-hydroxyvitamin D, to avoid problems of both undertreatment and overtreatment.
There is an urgent clinical and public health need for consensus cut-points for serum 25OHD inadequacy to avoid problems of both under- and overtreatment.
Osteopenia and rickets remain a problem for high-risk infants, especially preterm infants <1500 g birthweight (very low birth weight, VLBW). The primary cause of osteopenia in VLBW infants is a low ...intake of calcium and phosphorus compared to requirements for the rapidly growing skeleton. Human milk is a relatively low mineral containing substance and cannot meet the bone mineral needs of very low birth weight infants. As such, most VLBW infants need additional bone minerals and in many neonatal care units these are provided as part of human milk fortificants or specialized infant formulas. In some nurseries, these are given to all infants < 1800–2000 g birthweight. Management of full-term infants who are small for gestational age at birth is less clear, but in general bone mineral content is associated more with body size than gestational age and supplementation is often provided to these infants. Although all infants, including preterm ones need a source of vitamin D, the benefits of providing high doses of vitamin D to healthy preterm neonates is unproven. Some evidence indicates that most calcium absorption is non-vitamin D dependent in the first weeks of life in both preterm and term infants. However, after achieving full feeds in the preterm infant, it is prudent to provide vitamin D at amounts comparable to that used in full-term infants. Higher doses increase serum 25-hydroxyvitamin D levels more rapidly, but evidence is inconclusive as to the relative benefits vs possible risks of higher doses. In healthy full-term infants, although vitamin D provision via supplement drops to the breastfed infant, high dose maternal supplementation to the lactating mother or infant formula is generally recommended, the current evidence only strongly supports its use in identified at-risk infants.
An acute shortage of infant formulas in the United States occurred in early 2022, exacerbating a longer-standing, less severe shortage that has occurred over the last several years. The shortage has ...been particularly problematic for specialized formulas such as those needed for infants and children with food allergies, intestinal failure, kidney disease, and metabolic disorders. Although undoubtedly the magnitude of the current shortage will abate over time, it has affected many children and caused tremendous distress for thousands of families. We propose a series of interventions to be undertaken as soon as feasible to help ensure that the conditions that led to this problem do not recur and families regain confidence in the safety and supply reliability of formulas for infants and young children regardless of their medical needs.
The pediatrician plays a major role in helping optimize bone health in children and adolescents. This clinical report reviews normal bone acquisition in infants, children, and adolescents and ...discusses factors affecting bone health in this age group. Previous recommended daily allowances for calcium and vitamin D are updated, and clinical guidance is provided regarding weight-bearing activities and recommendations for calcium and vitamin D intake and supplementation. Routine calcium supplementation is not recommended for healthy children and adolescents, but increased dietary intake to meet daily requirements is encouraged. The American Academy of Pediatrics endorses the higher recommended dietary allowances for vitamin D advised by the Institute of Medicine and supports testing for vitamin D deficiency in children and adolescents with conditions associated with increased bone fragility. Universal screening for vitamin D deficiency is not routinely recommended in healthy children or in children with dark skin or obesity because there is insufficient evidence of the cost-benefit of such a practice in reducing fracture risk. The preferred test to assess bone health is dual-energy x-ray absorptiometry, but caution is advised when interpreting results in children and adolescents who may not yet have achieved peak bone mass. For analyses, z scores should be used instead of T scores, and corrections should be made for size. Office-based strategies for the pediatrician to optimize bone health are provided. This clinical report has been endorsed by American Bone Health.
Vitamin D is an essential nutrient for bone health and may influence the risks of respiratory illness, adverse pregnancy outcomes, and chronic diseases of adulthood. Because many countries have a ...relatively low supply of foods rich in vitamin D and inadequate exposure to natural ultraviolet B (UVB) radiation from sunlight, an important proportion of the global population is at risk of vitamin D deficiency. There is general agreement that the minimum serum/plasma 25‐hydroxyvitamin D concentration (25(OH)D) that protects against vitamin D deficiency–related bone disease is approximately 30 nmol/L; therefore, this threshold is suitable to define vitamin D deficiency in population surveys. However, efforts to assess the vitamin D status of populations in low‐ and middle‐income countries have been hampered by limited availability of population‐representative 25(OH)D data, particularly among population subgroups most vulnerable to the skeletal and potential extraskeletal consequences of low vitamin D status, namely exclusively breastfed infants, children, adolescents, pregnant and lactating women, and the elderly. In the absence of 25(OH)D data, identification of communities that would benefit from public health interventions to improve vitamin D status may require proxy indicators of the population risk of vitamin D deficiency, such as the prevalence of rickets or metrics of usual UVB exposure. If a high prevalence of vitamin D deficiency is identified (>20% prevalence of 25(OH)D < 30 nmol/L) or the risk for vitamin D deficiency is determined to be high based on proxy indicators (e.g., prevalence of rickets >1%), food fortification and/or targeted vitamin D supplementation policies can be implemented to reduce the burden of vitamin D deficiency–related conditions in vulnerable populations.
Here we report the outcome of a working group convened in January and March 2017 by the Sackler Institute for Nutrition Science at the New York Academy of Sciences and the Bill & Melinda Gates Foundation to assess the global prevalence and disease burden of vitamin D deficiency, and population‐based strategies to improve vitamin D status, particularly in low‐ and middle‐income countries. The working group aimed to examine definitions of vitamin D deficiency based on biomarkers and correlations with disease or health outcomes.
Background
Vitamin D deficiency is common worldwide, contributing to nutritional rickets and osteomalacia which have a major impact on health, growth, and development of infants, children and ...adolescents. Vitamin D levels are low in breast milk and exclusively breastfed infants are at risk of vitamin D insufficiency or deficiency.
Objectives
To determine the effect of vitamin D supplementation given to infants, or lactating mothers, on vitamin D deficiency, bone density and growth in healthy term breastfed infants.
Search methods
We used the standard search strategy of Cochrane Neonatal to 29 May 2020 supplemented by searches of clinical trials databases, conference proceedings, and citations.
Selection criteria
Randomised controlled trials (RCTs) and quasi‐RCTs in breastfeeding mother‐infant pairs comparing vitamin D supplementation given to infants or lactating mothers compared to placebo or no intervention, or sunlight, or that compare vitamin D supplementation of infants to supplementation of mothers.
Data collection and analysis
Two review authors assessed trial eligibility and risk of bias and independently extracted data. We used the GRADE approach to assess the certainty of evidence.
Main results
We included 19 studies with 2837 mother‐infant pairs assessing vitamin D given to infants (nine studies), to lactating mothers (eight studies), and to infants versus lactating mothers (six studies). No studies compared vitamin D given to infants versus periods of infant sun exposure.
Vitamin D supplementation given to infants: vitamin D at 400 IU/day may increase 25‐OH vitamin D levels (MD 22.63 nmol/L, 95% CI 17.05 to 28.21; participants = 334; studies = 6; low‐certainty) and may reduce the incidence of vitamin D insufficiency (25‐OH vitamin D < 50 nmol/L) (RR 0.57, 95% CI 0.41 to 0.80; participants = 274; studies = 4; low‐certainty). However, there was insufficient evidence to determine if vitamin D given to the infant reduces the risk of vitamin D deficiency (25‐OH vitamin D < 30 nmol/L) up till six months of age (RR 0.41, 95% CI 0.16 to 1.05; participants = 122; studies = 2), affects bone mineral content (BMC), or the incidence of biochemical or radiological rickets (all very‐low certainty). We are uncertain about adverse effects including hypercalcaemia. There were no studies of higher doses of infant vitamin D (> 400 IU/day) compared to placebo.
Vitamin D supplementation given to lactating mothers: vitamin D supplementation given to lactating mothers may increase infant 25‐OH vitamin D levels (MD 24.60 nmol/L, 95% CI 21.59 to 27.60; participants = 597; studies = 7; low‐certainty), may reduce the incidences of vitamin D insufficiency (RR 0.47, 95% CI 0.39 to 0.57; participants = 512; studies = 5; low‐certainty), vitamin D deficiency (RR 0.15, 95% CI 0.09 to 0.24; participants = 512; studies = 5; low‐certainty) and biochemical rickets (RR 0.06, 95% CI 0.01 to 0.44; participants = 229; studies = 2; low‐certainty). The two studies that reported biochemical rickets used maternal dosages of oral D3 60,000 IU/day for 10 days and oral D3 60,000 IU postpartum and at 6, 10, and 14 weeks. However, infant BMC was not reported and there was insufficient evidence to determine if maternal supplementation has an effect on radiological rickets (RR 0.76, 95% CI 0.18 to 3.31; participants = 536; studies = 3; very low‐certainty). All studies of maternal supplementation enrolled populations at high risk of vitamin D deficiency. We are uncertain of the effects of maternal supplementation on infant growth and adverse effects including hypercalcaemia.
Vitamin D supplementation given to infants compared with supplementation given to lactating mothers: infant vitamin D supplementation compared to lactating mother supplementation may increase infant 25‐OH vitamin D levels (MD 14.35 nmol/L, 95% CI 9.64 to 19.06; participants = 269; studies = 4; low‐certainty). Infant vitamin D supplementation may reduce the incidence of vitamin D insufficiency (RR 0.61, 95% CI 0.40 to 0.94; participants = 334; studies = 4) and may reduce vitamin D deficiency (RR 0.35, 95% CI 0.17 to 0.72; participants = 334; studies = 4) but the evidence is very uncertain. Infant BMC and radiological rickets were not reported and there was insufficient evidence to determine if maternal supplementation has an effect on infant biochemical rickets. All studies enrolled patient populations at high risk of vitamin D deficiency. Studies compared an infant dose of vitamin D 400 IU/day with varying maternal vitamin D doses from 400 IU/day to > 4000 IU/day. We are uncertain about adverse effects including hypercalcaemia.
Authors' conclusions
For breastfed infants, vitamin D supplementation 400 IU/day for up to six months increases 25‐OH vitamin D levels and reduces vitamin D insufficiency, but there was insufficient evidence to assess its effect on vitamin D deficiency and bone health. For higher‐risk infants who are breastfeeding, maternal vitamin D supplementation reduces vitamin D insufficiency and vitamin D deficiency, but there was insufficient evidence to determine an effect on bone health. In populations at higher risk of vitamin D deficiency, vitamin D supplementation of infants led to greater increases in infant 25‐OH vitamin D levels, reductions in vitamin D insufficiency and vitamin D deficiency compared to supplementation of lactating mothers. However, the evidence is very uncertain for markers of bone health. Maternal higher dose supplementation (≥ 4000 IU/day) produced similar infant 25‐OH vitamin D levels as infant supplementation of 400 IU/day. The certainty of evidence was graded as low to very low for all outcomes.
Historically, fruit juice was recommended by pediatricians as a source of vitamin C and as an extra source of water for healthy infants and young children as their diets expanded to include solid ...foods with higher renal solute load. It was also sometimes recommended for children with constipation. Fruit juice is marketed as a healthy, natural source of vitamins and, in some instances, calcium. Because juice tastes good, children readily accept it. Although juice consumption has some benefits, it also has potential detrimental effects. High sugar content in juice contributes to increased calorie consumption and the risk of dental caries. In addition, the lack of protein and fiber in juice can predispose to inappropriate weight gain (too much or too little). Pediatricians need to be knowledgeable about juice to inform parents and patients on its appropriate uses.
We summarize here lessons learned from studies on skeletal and extra-skeletal functions of vitamin D in hereditary 1,25-dihydroxyvitamin D–resistant rickets (HVDRR) patients with a mutant, ...nonfunctioning vitamin D receptor (VDR). During childhood, HVDRR patients are dependent on intestinal VDR, demonstrate low intestinal fraction calcium absorption, and have a bone calcium accretion rate that leads to hypocalcemia and rickets. After puberty, there is recovery in intestinal calcium absorption and in bone calcium accretion and structure. HVDRR monocytes and lymphocytes show impairment in the expression of antimicrobial proteins and demonstrate a proinflammatory cytokine profile. However, HVDRR patients do not exhibit increased rates of infections or inflammatory diseases. Vitamin D deficiency is associated with asthmatic exacerbations. Surprisingly, HVDRR patients do not usually develop asthma. They have normal allergic tests and lung functions and are protected against provoked bronchial hyperactivity. HVDRR patients have decreased IL-5 levels in their exhaled breath condensate. Given that IL-5 is a key cytokine in the development of airway inflammation and hyperactivity and that VDR is important for IL-5 generation, it is plausible that low lung IL-5 protects HVDRR patients from asthma. Vitamin D metabolites have suppressive effects on the renin angiotensin system. However, no HVDRR patient showed hypertension or echocardiographic pathology, and their renin angiotensin metabolites were normal. The VDR is expressed throughout the reproductive system, suggesting a role in reproduction. However, the reproductive history of HVDRR patients is normal despite the lack of a normal VDR. HVDRR patients provide a unique opportunity to study the role of the VDR and the role of vitamin D in various human systems.