Dr Natesan Thyagarajan
MBBS, DCH, MRCPCH (UK) CCST (UK)
Consultant paediatrician and Neonatologist
Sooriya hospital vadapalani Chennai.
Post graduate in paediatrics from Madras Medical College Chennai.
Worked in United Kingdom for several years and has completed the specialist
training in paediatrics and neonatology and was awarded MRCPCH, CCST by the Royal College of paediatrics and child health.
Has special interest in neonatology and developmental paediatrics.
Currently working as a consultant in Sooriya hospital vadapalani Chennai.
“Make hay while the sun shines” is a proverb and in day to day life make vitamin D while the sun shines
Vitamin D is a fat-soluble vitamin that is naturally present in very few foods. Vitamin D is mainly derived from the action of sunlight on 7-dehydrocholesterol in the skin, and vitamin D deficiency is more likely to occur in individuals with darker skins or in those whose skin extensively covered. The principal actions of Vitamin D are to stimulate absorption of calcium by the gut and promote mineralisation of bone.
Role of vitamin D
Vitamin D plays an integral part in maintaining bone health and its role in other body systems has also been identified. Its deficiency has been implicated as a risk factor for diabetes, ischemic heart diseases and tuberculosis in Asians. Currently the immune modulating effects of vitamin D are increasingly recognised. The multifaceted actions of Vitamin D are contributing to more and more implications of the Vitamin D in children.
Vitamin D is particularly important in infancy where infection incidence and severity are high and immune response is incomplete. Vitamin D status of the infant is closely correlated with maternal vitamin D status during pregnancy. A high prevalence of maternal vitamin D deficiency has been reported in recent years from many global regions. The vitamin D content of breast milk is low. Exclusively breastfed infants are at higher risk of vitamin D deficiency.
Deficiency of vitamin D
Vitamin deficiency in children is on the rise due to multiple factors
- Lack of adequate sun exposure
- Improper diet – High phytic acid dietary content
- Lack of physical activity
- Obesity
- Increasing prevalence of Vit D deficiency in pregnant mothers
- Use of sunscreen lotions, reducing sun exposed areas
“Paradox—-poverty among plenty”
The paradox of hypovitaminosis D in spite of abundant sunshine can be explained by various factors like duration and timing of sun exposure, amount of skin exposed, atmospheric pollution, and skin pigmentation, sunscreen use, dietary and genetic factors.
- Modern day life style changes have significantly reduced the total duration of sun exposure in children.
- UV-B, having shorter wavelength, tend to scatter earlier or later in the day and hence cutaneous vitamin D synthesis is maximum between 10 AM to 3 PM, the time when most of the children are either in school or indoors.
- Exposure of only face, hands and arms due to clothing versus whole body is associated with marked differences in vitamin D synthesis.
- Cloud cover, increasing water vapour and industrial pollution can reduce the amount of UV-B that reaches the earth’s surface.
Vitamin D deficiency effects in children and adults
- Rickets – deformities of their weight-bearing limbs, bow legs (genu varum) or knock knees (genu valgum). Other features of rickets include poor growth in height and weight, frontal bossing of the skull, swelling of wrists, knees and ankles
- Bone pain and muscle weakness
- Severe asthma in children
- Increased risk of death from cardiovascular disease and Immunological diseases
- Cognitive impairment in older adults
- Cancer
- Dental caries
Solutions:
Adequate exposure to sunlight
Eating Vitamin D rich natural food and foods fortified with Vitamin D
Supplementation of Vitamin D after consulting your doctor especially in new born babies
Avoiding excessive use of sunscreen lotions and covering of exposed areas
Foods rich in vitamin D
Very few foods in nature contain vitamin D. The flesh of fatty fish (such as salmon, tuna, and mackerel) and fish liver oils are among the best sources. Small amounts of vitamin D are found in beef liver, cheese, and egg yolks.
Milk and some brands of yogurt are fortified with vitamin D as well. Fortified breakfast cereals, breads, and orange juice may also contain Vitamin D.
Prevention is better than cure is most apt to vitamin D deficiency