Vitamin D Thru the Lifecycle.
Vitamin D is a vital fat soluble vitamin and hormone that is mainly sourced from synthesis in the human skin by natural exposure to sunlight. Foods such as Mushrooms, fatty fish and egg yolks possess vitamin D in nature. In some continents, cheese, milk, yogurt and cereals are fortified with vitamin D to supply the daily requirements but their contribution to the total amount of Vitamin D needed in the human body is often inadequate. Vitamin D helps to maintain the body’s level of calcium-phosphate by increasing their intestinal absorption for the mineralization of the bones. Some observational studies have shown that there are associations between low levels of vitamin D in adults and adolescents and conditions such as: cognitive function disorders, infectious diseases, glucose metabolism disorders, multiple sclerosis, mood disorders and obesity ( Ozhan, Evrengul, Agladioglu, Yasar, & Demir, 2016).
According to Muhairi, Mehairi, Khouri, Naqbi, Maskari, Al Kaabi, &Shah (2013), a study was conducted to determine the prevalence of vitamin D deficiency and its correlates in adolescents aged 15-18 years in the United Arab Emirates. The study was conducted in urban schools in Al Ain, Abu Dhabi Emirate, and it showed that the prevalence of the deficiency of vitamin D varied in boys and girls, (10%) and (28%) respectively. The study concluded that vitamin d inefficiency was highly prevalent in adolescents and its was more common in girls this was attached to the fact that, in the Arab countries Women have a conservative style of dress that is the hijab and niqab which covers most of the body when they are outside and thus there is inadequate exposure of the skin to sunlight.
In another study the frequency of seasonal Vitamin D inefficiency in adolescents was conducted in Istanbul city in Bağcılar, district. The study was conducted at the end of winter and at the end of summer. The results showed that the levels of vitamin at the end of winter were the same in both girls and boys whereas in the end of summer the vitamin D levels were significantly low in girls than boys. The group with sufficient dairy product consumption had significantly higher vitamin D levels in both end of summer and end of winter. The study concluded that it was important to provide supplemental vitamin D to overcome the deficiency seen especially at the end of summer( Erol, Yiğit,Küçük, & Gayret, 2015).
According to Karabel, Şimşek, Kenan , Kelekçi, bel, Tuncel, & Şahin (2016), a study was conducted on the roles of vitamin D and the parathormone during adolescence in which the frequency of depression is high. The results showed that frequency of depressive symptoms increased with decrease in vitamin D levels and increased PTH levels, independent of other factors. The prevention of depression, specifically in adolescents, is important to decrease possible suicidal and homicidal thoughts that might arise during adulthood, and substance abuse. Maintaining vitamin D support during adolescence, as with the first year of life, is necessary for both the prevention and treatment of depression.
The association between obesity and overweighting and vitamin D deficiency has been reported by many researchers. This is according to studies conducted on obese adolescents in Korea, Kuwait, Italy India, Oslo, Netherlands and Japan. Diabetes mellitus has also an association with vitamin D deficiency, for both type 1 and type 2 diabetes. Due to the importance of vitamin D deficiency and its negative health ( Taheri, Ghafari, Hajivandi,& Amiri ,2014)
Most of the studies show the importance of vitamin d to the human body and how its deficiency can affect adolescents. The studies also show the importance of both categories of vitamin D that is vitamin D2 and vitamin D3 this is because of its inadequacy in the body. The studies further show what limits the level of vitamin D and under what circumstances vitamin D will be low or high in individuals. They also bring out the relation between some conditions and the inefficiency of vitamin D (Palacios & Gonzalez 2014).
Ozhan, B., Evrengul, H., Agladioglu, S. Y., Yasar, S. Ü., & Demir, S. (2016). Vitamin D Status of Children in a University Hospital in West Turkey. HK J Paediatr (new series), 21(4), 251-256.
Karabel, M., Şimşek, Ş., Kenan Haspolat, Y., Kelekçi, S., Karabel, D., Tuncel, T., … & Şahin, C. (2016). The Association between Depression and Vitamin D and Parathyroid Hormone Levels in Adolescents. International Journal of Pediatrics, 4(2), 1365-1372.
Taheri, Z., Ghafari, M., Hajivandi, A., & Amiri, M. (2014). Vitamin D deficiency in children and adolescents; an international challenge. J Parathyr Dis, 2, 27-31.
Muhairi, S. J., Mehairi, A. E., Khouri, A. A., Naqbi, M. M., Maskari, F. A., Al Kaabi, J., … & Shah, S. M. (2013). Vitamin D deficiency among healthy adolescents in Al Ain, United Arab Emirates. BMC Public Health, 13(1), 33.
Erol, M., Yiğit, Ö., Küçük, S. H., & Gayret, Ö. B. (2015). Vitamin D Deficiency in Children and Adolescents in Bağcılar, İstanbul. Journal of clinical research in pediatric endocrinology, 7(2), 134.
Palacios, C., & Gonzalez, L. (2014). Is vitamin D deficiency a major global public health problem?. The Journal of steroid biochemistry and molecular biology, 144, 138-145.