Vitamin D in Children's Health

The impact of vitamin D deficiency on caries, periodontitis, and oral cancer: A systematic review

Background

The relationship between vitamin D deficiency with dental caries, periodontitis and oral cancer is controversial.

Objectives

This review aimed to systematically evaluate the published literature and summarise the available evidence about the impact of vitamin D deficiency (VDD) on the oral diseases mentioned above.

Methods

PubMed, Web of Science, Scopus and ScienceDirect databases were used. The search terms included were vitamin D, caries, periodontitis, and oral cancer. All papers published between January 2017 and November 2022 were included. The PRISMA process was used for the screening and selection studies.

Results

Initially, 3001 studies were identified. However, after evaluating 46 full-text articles that explored the link between VDD and caries, periodontitis, and oral cancer, only 32 studies met the inclusion criteria for this systematic review. Among these, 15 studies focused on caries, 16 on periodontitis, and only one on oral cancer. Regarding study quality and risk of bias, 25 out of the 32 studies were deemed to have low risk. A total of 12 studies on periodontitis showed the impact of VDD.

Conclusion

The review highlights that most evidence suggests an association between VDD and periodontitis. However, findings concerning the association between VDD and dental caries were controversial. Thus, further research is required to clarify the impacts of VDD on caries and oral cancer.

The Effect of Vitamin D Deficiency as a Risk Factor of Early Fragmentation in Legg-Calve-Perthes Disease: A Prospective Study

INTRODUCTION

Legg-Calve-Perthes disease (LCPD) is a disorder involving the hips in young children of preschool and school-going age groups, more common in 4-8 years. The insufficient blood supply to the femoral head is the main reason behind various etiologic theories. Multiple factors affect the natural progression of the disease. The natural progression of the disease involves early avascular necrosis, fragmentation, reconstitution, and healed stages. In the fragmentation stage, the bony epiphysis begins to fragment, and the subchondral radiolucent zone (crescent sign) is the result of a subchondral stress fracture, which later on determines the extent of a necrotic fragment of the femoral head. These changes later contribute to changes in the shape of the femur head and the extent of deformity. As vitamin D plays a vital role in the onset of the fragmentation stage, we conducted a study to assess the effect of vitamin D deficiency as a risk factor for early fragmentation in Legg-Calve-Perthes disease.

METHODS

In our study, 50 patients aged 4-12 years were examined over three years and classified according to Catterall and Herring's lateral pillar classification; the length of the fragmentation stage and the vitamin D level were considered. A vitamin D level of less than 20 ng/mL was labeled as the deficient group, 20-30 ng/mL as the insufficient group, and more than 30 ng/mL as the sufficient (normal) group.

RESULTS

The critical fragmentation stage was significantly longer (more than 12 months) in vitamin D deficiency (34%), leading to a higher risk of deformity and extrusion of the femoral head, which led to higher rates of surgical intervention and containment procedures.

CONCLUSION

The fragmentation stage is critical in the course of LCPD. Vitamin D levels play a vital role in predicting the prognostic of LCPD, and it should be measured in all patients of LCPD. Patients with normal vitamin D levels have a comparatively shorter fragmentation stage duration than patients with insufficient or deficient levels, leading to a lesser duration of femoral head damage.

Vitamin D Deficiency as a Risk Factor of Preeclampsia during Pregnancy

A balanced diet is achieved not only via the consumption of a variety of food products but also by ensuring that we take in sufficient quantities the micronutrients necessary for the adequate functioning of the human body, such as vitamins, an important one of which is vitamin D. Vitamin D has been closely linked to bone health. Vitamin D deficiency has often been associated with negative effects concerning several pregnancy adverse outcomes, the most important of which are the birth of SGA newborns, premature birth, and, finally, preeclampsia, which are discussed in this work. The aim of this review is to critically summarize and scrutinize whether the concentration of vitamin D in the blood serum of pregnant women in all its forms may be correlated with the risk of preeclampsia during pregnancy and whether vitamin D levels could act both as a protective agent or as a risk factor or even a prognostic measure of the disease. The association of vitamin D levels with the onset of preeclampsia was examined by searching the PubMed and Google Scholar databases. A total of 31 clinical trials were identified and included in this review, with the aim of summarizing the recent data concerning vitamin D levels and the risk of preeclampsia. Among them, 16 were published in the last five years, and 13 were published within the last a decade. Most studies showed a significant association between vitamin D deficiency and preeclampsia risk. It was also found that the higher the dose, the lower the risk of disease. Of the 31 articles, only 7 of them did not show a significant difference between vitamin D levels and preeclampsia regardless of comorbidity. The results of this review suggest that there is indeed an association between the concentration of vitamin D during pregnancy and the risk of preeclampsia; however, further studies are strongly recommended to derive conclusive evidence.

Clinical Toxicology of Vitamin D in Pediatrics: A Review and Case Reports

Intoxication of vitamin D is not a common case in pediatrics. Vitamin D supplements are sold as OTC drugs; however, there is a lack of public education about the permissible limits of vitamin D intake which may lead to vitamin D toxicity (VDT). This review aims to give insights to readers or practitioners about the clinical toxicology of vitamin D in pediatrics, which includes the mechanism of VDT, case reports, and the management of vitamin D poisoning. VDT refers to serum 25(OH)D levels, particularly when the level exceeds 100 ng/mL (250 nmol/L) or is defined as hypervitaminosis D. Hypercalcemia is a common condition of vitamin D toxicity. Vitamin D and its metabolites in moderate levels can induce hypercalcemia, as indicated by the elevation of osteoclastic bone resorption, the presence of calcium in renal tubules, intestinal calcium intake (through increased production of calcium-binding protein in enterocytes), and the decrease of parathyroid hormone synthesis. VDT in pediatrics can be managed by discontinuing vitamin D intake; using activated charcoal, furosemide, prednisone, and calcitonin; rehydration using intravenous sodium chloride 0.9%; and dextrose fluid therapy. It is important for parents to be more careful when providing vitamin D to their children.

Vitamin D-A Risk Factor for Bone Fractures in Children: A Population-Based Prospective Case-Control Randomized Cross-Sectional Study

BACKGROUND

Vitamin D is an essential component in calcium metabolism. Seasonality, advanced age, sex, dark skin pigmentation, and limited exposure to sunlight were reported as causes of vitamin D deficiency. This study aims to determine whether children with lower levels of vitamin D suffer more fractures than those with sufficient levels.

MATERIALS AND METHODS

Our institution underwent a prospective case-control randomized cross-sectional single-blinded study that included 688 children. They were split into two groups: the study group and the control group. The study group received supplements of vitamin D and calcium for 6 months. Another reference cohort was observed, which comprised 889 patients in the pediatric ward for different respiratory or gastroenterological conditions without a history of fractures. This group was used for age-sex matching tests.

RESULTS

Logistic regression showed that with every one unit increase of vitamin D level, the chance of having a middle third fracture in both bones of the forearm decreased by 7% (OR 1.07); distal third fracture incidence decreased by 1.03 times; middle third radius fracture incidence decreased by 1.03 times; distal third radius fracture incidence decreased by 1.06 times. The risk of having a distal third both-bone forearm fracture increased by 1.06 times with every year of age. Comparing the healing process, we noticed an improvement in bony callus formation for patients in the study group.

CONCLUSIONS

Dosing the serum level of 25-OH-vitamin D should be taken into consideration for pediatric low-energy trauma fractures. Supplementing with vitamin D and calcium throughout childhood can be a solution for healthy bones. Our preliminary results show that the normal level of vitamin D in children should start at 40 ng/mL.

Evaluation of vitamin D supplementation intake among children; cross-sectional observational study

BACKGROUND

The purpose of this study was to review the vitamin D supplementation intake status among children in the general public, determine the vitamin D supplements practices, and the barriers that parents and children face with supplementation.   Methods: A cross-sectional observational questionnaire-based survey study design was used. A convenience sampling technique was used to collect the data. An online Rao soft sample size calculator was applied to determine the sample size of 319. The response rate of participants was expected to be 63%, the margin of error was 5% and the level of confidence was 95%.   Results: A total of 248 parents (89.1% mothers (n =203)) and 15.7% fathers (n=39) with a mean ± SD age of 35.4 ± 7.04 years, completed the study (77.7% response rate). Parents reported that the supplements used the most by children were vitamin D supplements (21.85%) and multivitamins (21.8%) followed by calcium supplements (5.6%). However, 27.8% of children in this study did not take any supplements. Of all the parents, 65% (162) of them reported sending their child outside to play while 34.67% (86) of parents had reported no outdoor activity. Approximately 184 (74.2%) parents reported the child's diet to contain multiple natural sources of vitamin D. However, 69 (27.8%) parents reported giving none of the natural sources of vitamin D to their children through the diet. Parents with higher education about 62.9% (n=156) had a higher frequency of providing vitamin D supplements to their children. Children in high-income families (43.63%) were more likely to take vitamin D supplements than those in middle- or low-income families.     Conclusion: The study concluded that challenges like the educational and financial background of parents, family-income level, and health insurance status could help aid in addressing the overall burden of vitamin D deficiency among young children.

Evaluation of vitamin D supplementation intake among children; cross-sectional observational study

Background: The purpose of this study was to assess  the vitamin D supplementation intake status among children from different nationalities in the UAE,  to determine vitamin D intake practices through diet and lifestyle, and the barriers that parents in the UAE  face with providing vitamin D supplementation to their children.   Methods: A cross-sectional observational questionnaire-based survey study design was used.. The study was conducted in the U.A.E and the study participants were parents of children from ages 4-15 years. The questionnaire used in this study was both self-administered and interviewer-administered while inquiring the questions from the parents. A convenience sampling technique was used to collect the data. The response rate of participants was expected to be 63%, the margin of error was 5% and the level of confidence was 95%.   Results: A total of 248 participants (203 mothers, 39 fathers and 6 caregivers) completed the study. Participants reported that the supplements used the most by children were vitamin D supplements (21.85%), followed by multivitamins (21.8%) and calcium supplements (5.6%) and 27.8% of participants in this study reported  to  no  supplementation at all. The rate of vitamin D supplementation among children was higher in those families with higher income levels, parents/caregivers who were more educated, those families who attained health insurance. However, there was no statistical significance between these correlations. Conclusion: The study concluded that challenges like the educational and financial background of parents, family-income level, and health insurance status could help aid in addressing the overall burden of vitamin D deficiency among young children in the UAE. Pediatricians and health care professionals could use our study and use it as an aid to provide screening on lifestyle, sun light exposure, and dietary modifications and also educate parents why and how vitamin D is crucial for their children.

Association Between Season of Birth and Cognitive Aging in Older Adults: Pan-European Population-Based Study on 70,000 Individuals

BACKGROUND

Several early-life factors have been associated with higher risk of developing dementia. It is unclear whether season of birth (SOB) can affect cognitive aging in older adults or not.

OBJECTIVE

We aimed to study the association of SOB with the level of cognitive performance as well as with the rate of cognitive decline.

METHODS

We studied 70,203 individuals who participated in the Survey of Health, Aging and Retirement in Europe. Cognition was measured with tests on verbal fluency and immediate and delayed recall. We assessed the association of SOB with the level of cognitive performance using multiple linear regression and with the rate of cognitive decline using linear mixed-effects models.

RESULTS

When compared to individuals born in winter and adjusted for sociodemographic and health-related characteristics, being born in summer was associated with a higher level of delayed recall (B 0.05; 95%CI 0.01 to 0.09) and verbal fluency (B 0.15; 95%CI 0.00 to 0.29) and being born in fall with a higher level of immediate recall (B 0.04; 95%CI 0.01 to 0.08) and verbal fluency (B 0.15; 95%CI 0.01 to 0.29). Individuals born in summer had a higher yearly decline in delayed recall (B -0.005; 95%CI -0.009 to 0.000), while the scores in delayed recall in participants born in spring showed an inverse trend (B 0.005; 95%CI 0.000 to 0.010).

CONCLUSION

Individuals born in winter seem to carry a life-long disadvantage in a lower level of cognitive performance; however, being born in winter does not seem to affect the rate of cognitive decline.

Prevalence and predictors of vitamin D deficiency in young African children

BACKGROUND

Children living in sub-Saharan Africa have a high burden of rickets and infectious diseases, conditions that are linked to vitamin D deficiency. However, data on the vitamin D status of young African children and its environmental and genetic predictors are limited. We aimed to examine the prevalence and predictors of vitamin D deficiency in young African children.

METHODS

We measured 25-hydroxyvitamin D (25(OH)D) and typed the single nucleotide polymorphisms, rs4588 and rs7041, in the GC gene encoding the vitamin D binding protein (DBP) in 4509 children aged 0-8 years living in Kenya, Uganda, Burkina Faso, The Gambia and South Africa. We evaluated associations between vitamin D status and country, age, sex, season, anthropometric indices, inflammation, malaria and DBP haplotypes in regression analyses.

RESULTS

Median age was 23.9 months (interquartile range [IQR] 12.3, 35.9). Prevalence of vitamin D deficiency using 25(OH)D cut-offs of < 30 nmol/L and < 50 nmol/L was 0.6% (95% CI 0.4, 0.9) and 7.8% (95% CI 7.0, 8.5), respectively. Overall median 25(OH)D level was 77.6 nmol/L (IQR 63.6, 94.2). 25(OH)D levels were lower in South Africa, in older children, during winter or the long rains, and in those with afebrile malaria, and higher in children with inflammation. 25(OH)D levels did not vary by stunting, wasting or underweight in adjusted regression models. The distribution of Gc variants was Gc1f 83.3%, Gc1s 8.5% and Gc2 8.2% overall and varied by country. Individuals carrying the Gc2 variant had lower median 25(OH)D levels (72.4 nmol/L (IQR 59.4, 86.5) than those carrying the Gc1f (77.3 nmol/L (IQR 63.5, 92.8)) or Gc1s (78.9 nmol/L (IQR 63.8, 95.5)) variants.

CONCLUSIONS

Approximately 0.6% and 7.8% of young African children were vitamin D deficient as defined by 25(OH)D levels < 30 nmol/L and < 50 nmol/L, respectively. Latitude, age, season, and prevalence of inflammation and malaria should be considered in strategies to assess and manage vitamin D deficiency in young children living in Africa.

Evaluation of nutritional status in pediatric patients diagnosed with Covid-19 infection

Aim

The aim of this study was to evaluate the nutritional status, the nutritional effect on the risk of infection and the severity of the disease, and the contribution of nutrition to the course of the infection in pediatric patients diagnosed with coronavirus disease who required additional nutritional support after hospitalization.

Methods

The body weight, height, body mass index, upper arm circumference, and triceps skinfold thickness of 49 patients aged 1 month to 18 years and diagnosed with Covid-19 and then hospitalized at the Ankara City Hospital, Pediatric Health and Diseases Hospital, Pediatric Infection ward between 15 May and 15 June 2020 were measured. Total protein, albumin, prealbumin, selenium, zinc, ferritin, folate, and selenium, C, D, E, and B12 levels were studied from blood drawn simultaneously from the patients.

Results

A total of 49 patients aged 8–18 years were evaluated. The median age was 13 years (age range 8–18). The females made up 53% and the males 47% of the group. No patient needed intensive care admission. Only 3 patients received antibiotic treatment and the others were followed up without treatment. The weight was normal in 75% and the height was normal in 90%. Mid-arm circumference and triceps thickness were normal in 72% of the patients. Vitamin D deficiency was present in 82%, vitamin B12 deficiency in 18%, vitamin C deficiency in 17%, ferritin deficiency in 16%, folate deficiency in 15%, vitamin A deficiency in 13%, and vitamin E deficiency in 7%.

Conclusion

No patient required intensive care admission. Only 3 patients received antibiotic treatment and the others were followed up without treatment. Malnourishment was present in 3% of the patients while 9% were obese. Vitamin D deficiency was the most common vitamin deficiency while vitamin B12, vitamin C, Ferritin, vitamin A, vitamin E, and Folate deficiency were less common. Selenium and zinc levels were normal in all patients. There was no correlation between anthropometric values and susceptibility to childhood COVID-19 infection or the clinical course. It is possible that vitamin D deficiency increases susceptibility to the infection.

Frequency of Vitamin-D deficiency in children with Urinary tract infection: A descriptive cross-sectional study

Objective:

To determine Vitamin-D status in children with urinary tract infection.

Methods:

A Cross-sectional study was done at Pediatric Department, Liaquat University Hospital Hyderabad, from July 2019 to March 2020. A total of 172 children of either gender from 2 to 60 months of age with confirmed urinary tract infection (UTI) (having positive urine C/S report) were included in the study. The child who received antibiotics 48 hours prior or already on immunosuppressive drugs and steroids from previous health record or by taking clinically relevant history), children with CKD on vitamin-D supplementation, and known case of Vitamin-D deficiency were also excluded from the study. All study participants were evaluated for vitamin-D level by high performance liquid chromatography. Urine sample was collected for C/S and 1 cc venous blood was taken for Vitamin D status (ng/ml). The mean ± standard deviation (SD) and stratification was calculated for age, duration of urinary tract infection and vitamin-D level. Post stratification chi-square test was applied for all categorical variables at 95% confidence interval (CI) and P-value ≤0.05 was considered significant.

Results:

The average age of the patients was 41.51±18.34 months. There were 130 (75.58%) females and 40 (23.25%) males. Most common complaint of the children was fever 150 (87.21%). Vomiting was present in 31 (18.02%), abdominal pain 22 (12.79%) and dysuria in 15 (8.72%) children. A total of 129 (75%) children had pyelonephritis and 15 (25%) had cystitis. (Frequency of vitamin-D deficiency in children with diagnosed UTI was 45.93% (79/172). Mild vitamin D deficiency was present in 42 (53.16%) children, while moderate deficiency in 55 (69.62%) children. E. Coli was the most common pathogen in both mild and moderate vitamin D deficiency i.e., 20 (47.61) and 31 (56.36%) respectively.

Conclusion:

The frequency of urinary tract infection is more common in children having vitamin D deficiency.

Vitamin D Status and Usual Nutrient Intake of Filipino Children Aged 6–12 Years in Selected Areas in the Philippines: A 2018 National Nutrition Survey

Background. This study aimed to determine the prevalence of vitamin D deficiency, usual nutrient intake, and food sources of vitamin D of Filipino children aged 6–12 years in selected areas in the Philippines. Methods. The National Nutrition Survey (NNS) collected blood samples of children aged 6–12 years from selected study sites: Manila City and Quezon City in the National Capital Region (NCR); Cagayan Province and Baguio City in Luzon; Northern Samar and Siquijor in Visayas; and Butuan City and Sultan Kudarat in Mindanao. About 789 children aged 6–12 years participated in this study. Serum vitamin D was determined by electrochemiluminescence binding assay (ECLIA). Food intake data were collected using two-day nonconsecutive 24 h food recall. Usual nutrient intakes were estimated using Personal Computer Software for Intake Distribution Estimation (PC-SIDE) program. Results. The mean serum vitamin D of 25 (OH)D was 72.7 ± 0.67 μmol/L. The overall prevalence of combined vitamin D deficiency (<50 μmol/L) and insufficiency (51–74 μmol/L) among children aged 6–12 years was 60.6%. Females had a higher prevalence of vitamin D insufficiency compared to males. NCR (57.9%) had a higher deficiency compared to the other areas. The usual intake of vitamin D (2 μg/day) among children was below the adequate intake of 5 μg/day. The main food sources of vitamin D are coming from fish (53%), pork (19%), and egg/egg dishes (16%). Conclusion. This study revealed that there is a significantly high level of vitamin D insufficiency in children aged 6–12 years. Filipino females had higher prevalence of vitamin D deficiency and insufficiency compared to males. Among the areas, NCR has the highest prevalence of deficiency/insufficiency.

Children's Health in the Digital Age

Environmental studies, metabolic research, and state of the art research in neurobiology point towards the reduced amount of natural day and sunlight exposure of the developing child, as a consequence of increasingly long hours spent indoors online, as the single unifying source of a whole set of health risks identified worldwide, as is made clear in this review of currently available literature. Over exposure to digital environments, from abuse to addiction, now concerns even the youngest (ages 0 to 2) and triggers, as argued on the basis of clear examples herein, a chain of interdependent negative and potentially long-term metabolic changes. This leads to a deregulation of the serotonin and dopamine neurotransmitter pathways in the developing brain, currently associated with online activity abuse and/or internet addiction, and akin to that found in severe substance abuse syndromes. A general functional working model is proposed under the light of evidence brought to the forefront in this review.

The relation between circulating levels of vitamin D and parathyroid hormone in children and adolescents with overweight or obesity: Quest for a threshold

The level of serum 25-hydroxyvitamin D (25(OH)D) at which intact parathyroid hormone (iPTH) is maximally suppressed (suppression point) and below which PTH begins to rise (inflection point) has been used to define optimum 25(OH)D concentration. We aimed to study the association of circulating iPTH with 25(OH)D concentrations and to determine a 25(OH)D threshold associated with a significant iPTH suppression. This cross-sectional study was conducted on 198 boys and 180 girls, aged 6–13 years with BMI ≥ 1SD (WHO criteria) recruited from primary schools. Adjusted iPTH for BMI z-score, pubertal status, and dietary calcium was used. Nonlinear regression was used to model the relationship between 25(OH)D and iPTH and identify a suppression point for 25(OH)D at which iPTH reached a plateau. Piecewise regression analysis with a single knot for all possible values of 25(OH)D were fitted. Furthermore, 95% confidence intervals (95%CI) for those point had been calculated. The mean age (SD) of girls and boys was 9.1 (1.6) and 9.4 (1.7) years, respectively. Median 25(OH)D and iPTH were 13.8 ng/mL and 33.9 pg/mL in boys and 9.9 ng/mL and 47.8 ng/mL in girls, respectively. The equation in girls was: log-iPTH = 3.598+0.868 exp[(-0.190×25(OH)D. The point for near maximal suppression of iPTH by 25(OH)D for girls occurred at a 25(OH)D concentration of 20 ng/mL (95% CI: 7.1 to 32.2). No point of maximal suppression was found for boys. We also found a 25(OH)D threshold of 10 ng/mL (95% CI: 4.6 to 22.5) for girls (f: 9.8) by linear piecewise regression modeling of adjusted iPTH. No significant inflection point for boys was observed. In overweight/obese girls, when the concentration of 25(OH)D was higher than 20 ng/mL, an iPTH mean plateau level is reached, and when its concentrations approach 10 ng/mL, the slope of iPTH concentration has been accelerated.

Vitamin D supplementation for the prevention or depletion of side effects of therapy with alemtuzumab in multiple sclerosis

PURPOSE OF REVIEW

Not only the multiple sclerosis specialist but also the general neurologist and primary care practitioner are increasingly aware of possible adverse events (AEs) by treatment with alemtuzumab (over 47% risk of secondary autoimmune-mediated diseases). Vitamin D supplementation's effect (VDS) to reduce these autoimmune AEs is poorly performed in routine practice. This article seeks to justify why this simple, inexpensive, patient-friendly therapy should be seriously discussed.

RECENT FINDINGS

Patients who have developed autoimmunity also show a high basal level of IL-21, a cytokine which increases the growth of auto-reactive T-cells. For side effects such as thyroid dysfunction, autoimmune thrombocytopenia, autoimmune hemolytic anemia, autoimmune hepatitis, diabetes mellitus type 1, and alopecia areata/alopecia totalis, VDS may have an impact on the immunological mechanism, in particular lowering levels of IL-17 and IL-21.

SUMMARY

The potential role of vitamin D in influencing autoimmune diseases is evident. If a life-threatening side-effect can be prevented by high-dose VDS, it is ethical to initiate this add-on therapy despite contradictory results in studies on the effectiveness of VDS.

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.

Vitamin D in autistic children and healthy controls

Insufficient levels of vitamin D have been demonstrated by many authors as a risk factor for autistic patients, however, the causality has not been reliably elucidated. In the present study, levels of calcidiol were determined in group of autistic children and compared with age matched healthy children as controls. Suboptimal levels of calcidiol in more than 60 % of both autistic patients as well as of control group were found. No significant differences in vitamin D between autistic children and healthy controls were observed.