Vitamin D in respiratory diseases

Abstract

REVIEWVitamin D has traditionally been known for its role in bone homeostasis with its effects on calcium and phosphate absorption and secretion. However, new evidence is emerging of its effects on a number of other cells, especially the immune system. This article reviews the role of vitamin D as it pertains to the respiratory tract and respiratory diseases. Respir J 2017;23 (1) Vitamin D belongs to a group of fat-soluble secosteroids and is required for intestinal absorption of calcium (Ca 2+ ) and phosphate (PO 4 3-). In humans, vitamin D is present as ergocalciferol (vitamin D 2 ) or cholecalciferol (vitamin D 3 ), and both forms can be ingested from the diet and/or supplements. The body can also synthesise vitamin D from cholesterol when sun exposure is adequate, hence it has been nicknamed the 'sunshine vitamin' . [1] Recently, interest has grown in the role of vitamin D in many non-skeletal medical conditions, including respiratory infection and lung function. [2] Emerging evidence indicates that vitamin D-mediated innate immunity is important in host defences against respiratory tract pathogens. [3] Observational studies suggest that vitamin D deficiency increases the risk of respiratory infections, incident wheezing illness in children and adults, and can cause asthma exacerbations. Vitamin D also modulates regulatory T-cell function and interleukin-10 (IL-10) production, which may increase the therapeutic response to glucocorticoids in steroid-resistant asthma. S Afr HistoryIn 1914, American researchers McCollum and Davis discovered a substance in cod liver oil which was later called 'vitamin A' . In 1922, McCollum tested modified cod liver oil in which the vitamin A had been denatured. The modified oil cured rickets in sick dogs, so McCollum concluded the factor in cod liver oil that cured rickets was distinct from vitamin A. He called it vitamin D because it was the fourth vitamin to be named. [4] In 1923, American biochemist Harry Steenbock demonstrated that the irradiation of foodstuffs, especially milk, led to a cure for rickets. In 1932, an academic collaboration between Bourdillon, Rosenheim, King and Callow led to the isolation and characterisation of vitamin D and later in the 1930s, Windaus further clarified the chemical structure of vitamin D. By 1972, Holick had discovered that vitamin D was metabolised to two active forms, i.e. calcidiol and calcitriol. [5,6] Recommended dietary allowance of vitamin DThe US Institute of Medicine (IOM) recommended dietary allowance of vitamin D is 400 international units (IU) per day for children younger than 1 year of age, 600 IU per day for children at least 1 year of age and adults up to 70 years, and 800 IU per day for older adults.The US IOM concluded that serum 25-hydroxyvitamin D (25(OH)D) of 20 ng/mL or more would cover the requirements of 97.5% of the population. [7] The US Endocrine Society's Clinical Practice Guidelines suggest that 400 -1 000 IU/day may be needed for children aged <1 year, 600 -1 000 IU/day for children aged ≥1 year, and 1 500 ...

Pengaruh Jenis dan Pola Konsumsi Makanan yang Mengandung Vitamin D Terkait Gangguan Fungsi Paru pada Tukang Bangunan

“…Suplementasi dengan vitamin D tampaknya meningkatkan banyak kondisi paru-paru. Bukti untuk suplementasi vitamin D tidak begitu jelas dalam penyakit saluran nafas obstruktif seperti PPOK dan asma, tetapi itu pasti bermanfaat dalam tuberkulosis, dan bukti baru memuncak itu mungkin berguna pada pasien dengan infeksi saluran pernafasan akut, terutama pada individu yang kekurangan vitamin D [6].…”

Determinants of Dietary Vitamin D Intake in Population-Based Cohort Sample of Polish Female Adolescents

“…It is also important for the functioning of the heart and kidneys [12,13], the nervous [14,15], and digestive [16] systems, as well as the female and male reproductive systems [17]. The results of many in vivo and in vitro studies indicate that vitamin D deficiency is also associated with an increased risk for respiratory diseases [18], or certain cancers [19]. Obesity [20] and other metabolic syndrome components [21], type 2 diabetes mellitus [22], sarcopenia [23], polycystic ovary syndrome and other gynecological and obstetric diseases [17], and depression [24] are also disorders related to vitamin D deficiency.…”