{"id":1291,"date":"2021-07-08T20:16:00","date_gmt":"2021-07-08T14:46:00","guid":{"rendered":"https:\/\/www.diabetesasia.org\/magazine\/?p=1291"},"modified":"2025-03-20T10:59:56","modified_gmt":"2025-03-20T05:29:56","slug":"vitamin-d-deficiency-or-hypovitaminosis-d","status":"publish","type":"post","link":"https:\/\/www.diabetesasia.org\/magazine\/vitamin-d-deficiency-or-hypovitaminosis-d\/","title":{"rendered":"Vitamin D deficiency\u00a0or\u00a0hypovitaminosis D"},"content":{"rendered":"<p><strong>Vitamin D deficiency<\/strong>\u00a0or\u00a0<strong>hypovitaminosis D<\/strong><\/p>\n<p>is defined as a vitamin D level that is below normal. It most commonly occurs when they have inadequate sunlight exposure (in particular sunlight with adequate ultraviolet B rays (UVB)). Vitamin D deficiency can also be caused by inadequate nutritional intake of vitamin D, disorders limiting vitamin D absorption, and conditions impairing vitamin D conversion into active metabolites\u2014including certain liver, kidney, and hereditary disorders. Deficiency impairs bone mineralization, leading to bone-softening diseases such as rickets in children. It can also worsen osteomalacia and osteoporosis in adults, leading to an increased risk of bone fractures.\u00a0 \u00a0 \u00a0 Muscle weakness is also a common symptom of vitamin D deficiency, further increasing the risk of falls and bone fractures in adults. Vitamin D deficiency is associated with the development of schizophrenia.<\/p>\n<p>Vitamin D can be synthesized in the skin underexposed to UVB from sunlight. Oily fish\u00a0such as\u00a0salmon,\u00a0herring, and\u00a0mackerel\u00a0are also sources of vitamin D, as are\u00a0mushrooms.\u00a0Milk is often fortified with vitamin D, and sometimes bread, juices, and other dairy products are fortified with vitamin D as well.\u00a0Many\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Multivitamin\">multivitamins<\/a>\u00a0now contain vitamin D in different amounts.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-8668 aligncenter\" src=\"https:\/\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/what-is-vitamin-d-deficiency-300x200.avif\" alt=\"Vitamin D deficiency\u00a0or\u00a0hypovitaminosis D\" width=\"446\" height=\"297\" srcset=\"https:\/\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/what-is-vitamin-d-deficiency-300x200.avif 300w, https:\/\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/what-is-vitamin-d-deficiency-1024x683.avif 1024w, https:\/\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/what-is-vitamin-d-deficiency-768x512.avif 768w, https:\/\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/what-is-vitamin-d-deficiency.avif 1200w\" sizes=\"auto, (max-width: 446px) 100vw, 446px\" \/><\/p>\n<p>Mapping of several bone diseases onto levels of vitamin D (calcidiol) in the blood<\/p>\n<h4>Normal bone vs. Osteoporosis<\/h4>\n<p>Vitamin D deficiency is typically diagnosed by measuring the concentration of the\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Calcifediol\">25-hydroxyvitamin D<\/a>\u00a0in the blood, which is the most accurate measure of stores of vitamin D in the body.\u00a0One\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Nanogram\">nanogram<\/a>\u00a0per\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Millilitre\">milliliter<\/a>\u00a0(1\u00a0ng\/mL) is equivalent to 2.5\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Nanomole\">nanomoles<\/a> per liter (2.5 nmol\/L).<\/p>\n<ul>\n<li>Severe deficiency: &lt;12\u00a0ng\/mL = &lt;30\u00a0nmol\/L<\/li>\n<li>Deficiency: &lt;20\u00a0ng\/mL = &lt;50\u00a0nmol\/L<\/li>\n<li>Insufficient: 20\u201329\u00a0ng\/mL = 50\u201375\u00a0nmol\/L<\/li>\n<li>Normal: 30\u201350\u00a0ng\/mL = 75\u2013125\u00a0nmol\/L<\/li>\n<\/ul>\n<p>Vitamin D levels falling within this normal range prevent clinical manifestations of vitamin D insufficiency as well as\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Hypervitaminosis_D\">vitamin D toxicity<\/a>.<\/p>\n<p>Signs, symptoms, and associated <a href=\"https:\/\/www.diabetesasia.org\/hindimagazine\/%e0%a4%b5%e0%a4%bf%e0%a4%9f%e0%a4%be%e0%a4%ae%e0%a4%bf%e0%a4%a8-%e0%a4%a1%e0%a5%80-%e0%a4%95%e0%a5%80-%e0%a4%95%e0%a4%ae%e0%a5%80\/\">disorders<\/a><\/p>\n<p><strong><a href=\"https:\/\/heatingforce.co.uk\/blog\/keep-house-warm-winter\/\">Related: The Complete Guide to Keeping Your House Warm in the Winter<\/a><\/strong><\/p>\n<p>https:\/\/heatingforce.co.uk\/blog\/keep-house-warm-winter\/<\/p>\n<h4>Child with rickets<\/h4>\n<p>Vitamin D deficiency may only be detected on blood tests, but is the cause of some bone diseases and is associated with other conditions:<\/p>\n<ul>\n<li>Rickets, a childhood disease characterized by impeded growth and deformity of the\u00a0long bones.\u00a0The earliest sign of vitamin\u00a0D deficiency is\u00a0craniotabes, abnormal softening or thinning of the skull.<\/li>\n<li>Osteomalacia, a bone-thinning disorder that occurs exclusively in adults and is characterized by\u00a0proximal\u00a0muscle weakness and bone fragility. Women with vitamin D deficiency who have been through multiple pregnancies are at elevated risk of Osteomalacia.<\/li>\n<li>Osteoporosis, a condition characterized by reduced\u00a0bone mineral density\u00a0and increased bone fragility.<\/li>\n<li>Increased risk of fracture<\/li>\n<li>Muscle aches, weakness, and twitching (fasciculations) due to reduced blood calcium (hypocalcemia).<\/li>\n<li>Periodontitis, local inflammatory bone loss that can result in tooth loss.<\/li>\n<li>Pre-eclampsia: There has been an association between vitamin D deficiency and women who develop pre-eclampsia in pregnancy. The exact relationship of these conditions is not well understood. Maternal vitamin D deficiency may affect the baby, causing overt bone disease from before birth and impairment of bone quality after birth.<\/li>\n<li>Respiratory infections\u00a0and\u00a0COVID-19: Vitamin D deficiency may increase the risk of severe acute respiratory infections and\u00a0COPD.\u00a0Emerging studies have suggested a link between vitamin D deficiency and\u00a0COVID-19 symptoms. A review has shown that vitamin D deficiency is not associated with a higher chance of having COVID-19 but is associated with greater severity of the disease, including 80% increases in hospitalization and mortality rates.<\/li>\n<li>Schizophrenia: Vitamin D deficiency is associated with the development of\u00a0schizophrenia.\u00a0People with schizophrenia generally have lower levels of vitamin D.\u00a0The\u00a0environmental risk factors of the seasonality of birth, latitude, and migration linked to schizophrenia all implicate vitamin D deficiency, as do other health conditions such as maternal obesity. Vitamin D is essential for the normal development of the nervous system. Maternal vitamin D deficiency can cause prenatal neurodevelopmental defects, which influence neurotransmission, altering brain rhythms and dopamine metabolism.\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Vitamin_D_receptor\">Vitamin D receptors<\/a>,\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/CYP27B1\">CYP27B1<\/a>\u00a0and\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/CYP24A1\">CYP24A1<\/a>, are found in various brain regions, showing that vitamin D is a neuroactive, neurosteroid hormone essential for the development of the brain and normal function.\u00a0Inflammation as a causative factor in schizophrenia is normally suppressed by vitamin D.<\/li>\n<\/ul>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\" wp-image-8669 aligncenter\" src=\"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/images-6.jpg?resize=403%2C398&#038;ssl=1\" alt=\"Child with rickets\" width=\"403\" height=\"398\" \/><\/p>\n<p class=\"entry-title fn\"><strong><a href=\"https:\/\/thebestisup.com\/beginners-guide-to-learning-to-swim\/\">Related: A BEGINNER\u2019S GUIDE TO LEARNING TO SWIM<\/a><\/strong><\/p>\n<h4>Pathophysiology<\/h4>\n<p><strong>Decreased exposure of the skin to sunlight<\/strong> is a common cause of vitamin D deficiency.\u00a0People with\u00a0<strong>darker skin<\/strong>\u00a0pigment with increased amounts of\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Melanin\">melanin<\/a>\u00a0may have decreased production of vitamin D.\u00a0Melanin absorbs ultraviolet B radiation from the sun and reduces vitamin D production.\u00a0Sunscreen can also reduce vitamin D production.\u00a0Medications may speed up the metabolism of vitamin D, causing a deficiency.<\/p>\n<p><strong>Liver diseases:<\/strong> The liver must transform vitamin D into\u00a025-hydroxyvitamin D. This is an inactive metabolite of vitamin D but is a necessary precursor (building block) to create the active form of vitamin D.<\/p>\n<p><strong>Kidney disease:<\/strong> The kidneys are responsible for converting 25-hydroxyvitamin D to 1,25-hydroxyvitamin D. This is the active form of vitamin D in the body. Kidney disease reduces 1,25-hydroxyvitamin D formation, leading to deficient effects of vitamin D.<\/p>\n<p><strong>Intestinal conditions<\/strong>\u00a0that result in\u00a0malabsorption\u00a0of nutrients may also contribute to vitamin D deficiency by decreasing the amount of vitamin D absorbed via diet.\u00a0In addition, a vitamin D deficiency may lead to decreased absorption of calcium by the\u00a0intestines, resulting in increased production of\u00a0osteoclasts\u00a0that may break down a person&#8217;s bone matrix.\u00a0In states of\u00a0hypocalcemia, calcium will leave the bones and\u00a0may give rise to\u00a0secondary hyperparathyroidism, which is a response by the body to increase serum calcium levels. The body does this by increasing calcium uptake by the kidneys and continuing to take the calcium away from the bones. If prolonged, this may lead to osteoporosis\u00a0in adults and\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Rickets\">rickets<\/a>\u00a0in children.<\/p>\n<p>Risk factors<\/p>\n<p>Those most likely to be affected by vitamin D deficiency are people with little exposure to sunlight. Certain climates, dress habits, the avoidance of sun exposure, and the use of too much sunscreen protection can all limit vitamin D production.<\/p>\n<p><strong>Age<\/strong><\/p>\n<p>Older adults have a higher risk of having a vitamin D deficiency due to several risk factors, including decreased sunlight exposure, decreased intake of vitamin D in the diet, and decreased skin thickness, leading to further decreased absorption of vitamin D from sunlight.<\/p>\n<p><strong>Fat percentage<\/strong><\/p>\n<p>Since vitamin D<sub>3<\/sub>\u00a0(<a href=\"https:\/\/en.wikipedia.org\/wiki\/Cholecalciferol\">cholecalciferol<\/a>) and vitamin D<sub>2<\/sub>\u00a0(<a href=\"https:\/\/en.wikipedia.org\/wiki\/Ergocalciferol\">ergocalciferol<\/a>) are\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Vitamin#Classification\">fat-soluble<\/a>, humans and other animals with a skeleton need to store <a href=\"https:\/\/en.wikipedia.org\/wiki\/Adipose_tissue\">fat<\/a>. Without fat, the animal will have a hard time absorbing vitamin D<sub>2<\/sub>\u00a0and vitamin D<sub>3. The<\/sub>\u00a0lower the fat percentage, the greater the risk of vitamin deficiency, which is true in some athletes who strive to get as lean as possible.<\/p>\n<p><strong>Malnutrition<\/strong><\/p>\n<p>Although rickets and osteomalacia are now rare in Britain, osteomalacia outbreaks in some immigrant communities included women with seemingly adequate daylight outdoor exposure wearing typical Western clothing. Having darker skin and reduced exposure to sunshine did not produce rickets unless the diet deviated from a Western omnivore pattern characterized by high intakes of meat, fish, and eggs and low intakes of high-extraction <a href=\"https:\/\/en.wikipedia.org\/wiki\/Cereals\">cereals<\/a>. In sunny countries where rickets occur among older toddlers and children, rickets have been attributed to low dietary calcium intake. This is characteristic of cereal-based diets with limited access to dairy products. Rickets was formerly a major public health problem among the US population; in <a href=\"https:\/\/en.wikipedia.org\/wiki\/Denver\">Denver<\/a>, where ultraviolet rays are about 20% stronger than at sea level on the same latitude, almost two-thirds of 500 children had mild rickets in the late 1920s. An increase in the proportion of animal protein in the 20th-century American diet coupled with increased consumption of milk fortified with relatively small quantities of vitamin D coincided with a dramatic decline in the number of rickets cases. One study of children in a hospital in Uganda showed no significant difference in vitamin D levels of malnourished children compared to non-malnourished children. Because both groups were at risk due to darker skin pigmentation, both groups had vitamin D deficiency. Nutritional status did not appear to play a role in this study.<\/p>\n<p><strong>Obesity<\/strong><\/p>\n<p>There is an increased risk of vitamin D deficiency in people who are considered overweight or obese based on their\u00a0body mass index (BMI) measurement. The relationship between these conditions is not well understood. Different factors could contribute to this relationship, particularly diet and sunlight exposure. Alternatively, vitamin D is fat-soluble; therefore, excess amounts can be stored in fat tissue and used during winter when sun exposure is limited.<\/p>\n<p><strong>Sun exposure<\/strong><\/p>\n<p>The use of\u00a0sunscreen\u00a0with a\u00a0sun protection factor of 8 can theoretically inhibit more than 95% of vitamin D production in the skin.\u00a0In practice, however, sunscreen is applied to have a negligible effect on vitamin D status.\u00a0The vitamin D status of those in\u00a0Australia\u00a0and\u00a0New Zealand is unlikely to have been affected by campaigns advocating sunscreen. Instead, wearing clothing is more effective at reducing skin exposure to UVB and reducing natural vitamin D synthesis. Clothing that covers a large portion of the skin, when worn regularly and regularly, such as the burqa, is correlated with lower vitamin D levels and an increased prevalence of vitamin D deficiency.<\/p>\n<p>Regions far from the equator have a high seasonal variation in the amount and intensity of sunlight. In the UK, the prevalence of low vitamin D status in children and adolescents is higher in winter than in summer.\u00a0Lifestyle factors such as indoor versus outdoor work and time spent in\u00a0outdoor<a href=\"https:\/\/en.wikipedia.org\/wiki\/Outdoor_recreation\"> recreation<\/a>\u00a0play an important role.<\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\" wp-image-8670 aligncenter\" src=\"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/images-1-1.jpg?resize=509%2C326&#038;ssl=1\" alt=\"Child with rickets\" width=\"509\" height=\"326\" \/><\/p>\n<p>Additionally, vitamin D deficiency has been associated with urbanization in terms of air pollution, which blocks UV light, and an increase in the number of people working indoors. The elderly are generally exposed to less UV light due to hospitalization, immobility, institutionalization, and being housebound, leading to decreased vitamin D levels.<\/p>\n<p><strong>Darker skin color<\/strong><\/p>\n<p>The reduced\u00a0pigmentation\u00a0of\u00a0light-skinned individuals may result in higher vitamin D levels because of the\u00a0melanin, which acts as a sunblock; dark-skinned individuals may have higher vitamin D deficiency levels. Three to five times greater sun exposure is necessary for naturally darker-skinned people to produce the same amount of vitamin D as those with a white skin tone.<\/p>\n<p><strong>Malabsorption<\/strong><\/p>\n<p>Rates of vitamin D deficiency are higher among people with untreated\u00a0celiac disease, inflammatory bowel disease,\u00a0exocrine pancreatic insufficiency\u00a0from\u00a0cystic fibrosis, and\u00a0short bowel syndrome, which can all produce malabsorption problems. Vitamin D deficiency is also more common after surgical procedures reduce absorption from the intestine, including weight loss procedures.<\/p>\n<p><strong>Critical illness<\/strong><\/p>\n<p>Vitamin D deficiency is associated with increased mortality in critical illnesses. Before being admitted for intensive care, people who take vitamin D supplements are less likely to die than those who do not take vitamin D supplements.\u00a0Additionally, vitamin D levels decline during stays in intensive care.\u00a0Vitamin D<sub>3<\/sub> (cholecalciferol) or calcitriol given orally may reduce the mortality rate without significant adverse effects.<\/p>\n<p>Diagnosis<\/p>\n<p><em>See also:\u00a0<\/em><a href=\"https:\/\/en.wikipedia.org\/wiki\/Reference_ranges_for_blood_tests#Vitamins\"><em>Reference ranges for blood tests \u00a7\u00a0Vitamins<\/em><\/a>.<\/p>\n<p>The serum concentration of\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Calcifediol\">calcifediol<\/a>, also called 25-hydroxyvitamin D (abbreviated 25(OH)D), is typically used to determine vitamin D status. Most vitamin D is converted to 25(OH)D in the serum, giving an accurate picture of vitamin D status. The serum level of serum 1,25(OH)D is not usually used to determine vitamin D status because it is often regulated by other hormones in the body, such as a parathyroid hormone. The levels of 1,25(OH)D can remain normal even when a person may be vitamin D deficient. A serum level of 25(OH)D is the laboratory test ordered to indicate whether or not a person has vitamin D deficiency or insufficiency. It is also considered reasonable to treat at-risk persons with vitamin D supplementation without checking the level of 25(OH)D in the serum, as vitamin D toxicity has only been rarely reported to occur.<\/p>\n<p>Levels of 25(OH)D that are consistently above 200\u00a0nanograms\u00a0per\u00a0milliliter\u00a0(ng\/mL) (or 500\u00a0nanomoles per liter, nmol\/L) are thought to be potentially toxic, although data from humans are sparse.\u00a0Vitamin D toxicity usually results from taking supplements in excess.\u00a0Hypercalcemia is often the cause of symptoms,\u00a0and levels of 25(OH)D above 150\u00a0ng\/mL (375\u00a0nmol\/L) are usually found, although in some cases, 25(OH)D levels may appear to be normal. Periodic measurement of serum calcium in individuals receiving large doses of vitamin D is recommended.<\/p>\n<p>Screening<\/p>\n<p>The official recommendation from the\u00a0United States Preventive Services Task Force is that for persons who do not fall within an at-risk population and are asymptomatic, there is not enough evidence to prove that there is any benefit in screening for vitamin D deficiency.<\/p>\n<p>Treatment<\/p>\n<table>\n<tbody>\n<tr>\n<td><\/td>\n<td width=\"809\">This article needs to be\u00a0<strong>updated<\/strong>. Would you please update this article to reflect recent events or newly available information? <em>(January 2021)<\/em><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Vitamin D<sub>2<\/sub>\u00a0supplements<\/p>\n<p>In the United States and Canada, as of 2016, the amount of vitamin D recommended is 400 IU per day for children, 600 IU per day for adults, and 800 IU per day for people over age 70. The\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Canadian_Paediatric_Society\">Canadian Paediatric Society<\/a>\u00a0recommends that pregnant or breastfeeding women consider taking 2000 IU\/day, that all babies who are exclusively breastfed receive a supplement of 400 IU\/day, and that babies living north of 55\u00b0N get 800 IU\/day from October to April.<\/p>\n<p>Treating vitamin D deficiency depends on the severity of the deficit. Treatment involves an initial high-dosage treatment phase until the required serum levels are reached, followed by maintaining the acquired levels. The lower the 25(OH)D serum concentration before treatment, the higher the dosage needed to reach an acceptable serum level quickly.<\/p>\n<p>The initial high-dosage treatment can be given daily or weekly or can be given in the form of one or several single doses (also known as <em>stoss therapy<\/em>, from the German word\u00a0<em>Sto\u00df<\/em>\u00a0&#8216;push&#8217;).<\/p>\n<p>Therapy prescriptions vary, and there is no consensus on how best to arrive at an optimum serum level. While there is evidence that vitamin D<sub>3<\/sub>\u00a0raises 25(OH)D blood levels more effectively than vitamin D<sub>2,<\/sub>\u00a0other evidence indicates that D<sub>2<\/sub>\u00a0and D<sub>3<\/sub>\u00a0are equal for maintaining 25(OH)D status.<\/p>\n<p><strong>Initial phase<\/strong><\/p>\n<p><strong>Daily weekly or monthly dose<\/strong><\/p>\n<p>For treating rickets, the\u00a0American Academy of Pediatrics (AAP) has recommended that pediatric patients receive an initial two- to three-month treatment of &#8220;high-dose&#8221; vitamin D therapy. In this regime, the daily dose of cholecalciferol is 1,000 IU for newborns, 1,000 to 5,000 IU for 1- to 12-month-old infants, and 5,000 IU for patients over 1 year of age.<\/p>\n<p>For adults, other dosages have been called for. A review of 2008\/2009 recommended dosages of 1,000 IU cholecalciferol per 10 ng\/ml required serum increase, to be given daily over two to three months. In another proposed cholecalciferol loading dose guideline for vitamin D-deficient adults, a weekly dosage is given, up to a total amount proportional to the required serum increase (up to the level of 75 nml\/l), within certain bodyweight limits, to body weight.<\/p>\n<p>According to new data and practices relevant to vitamin D levels in the general population in France to establish optimal vitamin D status and frequency of intermittent supplement dosing,\u00a0patients with or at high risk for osteoporosis and vitamin D deficiency should start supplementation with a loading phase consisting of 50,000 IU weekly of vitamin D for 8 weeks in patients with levels &lt;20\u00a0ng\/mL and 50,000 IU weekly for 4 weeks in patients with levels between 20 and 30\u00a0ng\/mL. Subsequently, long-term supplementation should be prescribed as 50,000 IU monthly. Should pharmaceutical forms suitable for daily supplementation become available, patients displaying good treatment adherence could take a daily dose determined based on the 25(OH)D level.<\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\" wp-image-8671 aligncenter\" src=\"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?resize=531%2C237&#038;ssl=1\" alt=\"Vitamin-D-Deficiency\" width=\"531\" height=\"237\" srcset=\"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?resize=300%2C134&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?resize=1024%2C458&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?resize=768%2C344&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?resize=1536%2C688&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?w=1861&amp;ssl=1 1861w, https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D-Deficiency.jpg?w=1280&amp;ssl=1 1280w\" sizes=\"auto, (max-width: 531px) 100vw, 531px\" \/><\/p>\n<p>Until now, no consistent data suggest the ideal regimen of supplementation with vitamin D, and the question of the ideal time between doses is still of debate. Ish-Shalom et al. performed a study in older women to compare the efficacy and safety of a daily dose of 1500 IU to a weekly dose of 10,500 IU and 45,000 IU given every 28 days for two months. They concluded that supplementation with vitamin D could be equally achieved with daily, weekly, or monthly dosing frequencies. Another study comparing daily, weekly, and monthly vitamin D supplementation in deficient patients was published by Takacs et al. They reported equal efficacy of 1000 IU taken daily, 7000 IU taken weekly, and 30,000 IU taken monthly. Nevertheless, these consistent findings differ from the report by Chel et al. in which a daily dose was more effective than a monthly dose. The compliance calculation could be questionable in that study, as only random samples of the returned medications were counted. In a study by De Niet et al., 60 subjects with vitamin D deficiency were randomized to receive 2,000 IU vitamin D3 daily or 50,000 IU monthly. They reported similar efficacy of the two dosing frequencies, with the monthly dose providing more rapid normalization of vitamin D levels.<\/p>\n<p><strong>Single-dose therapy<\/strong><\/p>\n<p>Alternatively, a single-dose therapy is used, for instance, if there are concerns regarding the patient&#8217;s <a href=\"https:\/\/en.wikipedia.org\/wiki\/Compliance_(medicine)\">compliance<\/a>. The single-dose therapy can be given as an injection but is normally given in oral medication.<\/p>\n<p><strong>Vitamin D doses and meals<\/strong><\/p>\n<p>The presence of a meal and the fat content of that meal may also be important. Because vitamin D is\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/Vitamin#Classification\">fat-soluble<\/a>, it is hypothesized that absorption would be improved if patients are instructed to take their supplements with a meal. Raimundo et al. performed different studies confirming that a high-fat meal increased the absorption of vitamin D3 as measured by serum 25(OH) D. A clinical report indicated that serum 25(OH) D levels increased by an average of 57% over a 2-month to the 3 months in 17 clinic patients after they were instructed to take their usual dose of vitamin D with the largest meal of the day. Another study conducted on 152 healthy men and women concluded that diets rich in monounsaturated fatty acids might improve, and those rich in polyunsaturated fatty acids may reduce the effectiveness of vitamin D3 supplements; in another study performed by Cavalier E. et al., 88 subjects received orally a single dose of 50,000 IU of vitamin D3 solubilized in an oily solution as two ampoules each containing 25,000 IU (D\u2010CURE\u00ae, Laboratories SMB SA, Brussels, Belgium) with or without a standardized high\u2010fat breakfast. No significant difference between fasting vs. fed conditions was observed.<\/p>\n<p><strong>Maintenance phase<\/strong><\/p>\n<p>Once the desired serum level has been achieved, be it by a high daily or weekly, or monthly dose or by a single-dose therapy, the AAP recommendation calls for a maintenance supplementation of 400 IU for all age groups, with this dosage being doubled for premature infants, dark-skinned infants and children, children who reside in areas of limited sun exposure (&gt;37.5\u00b0 latitude), obese patients, and those on certain medications.<\/p>\n<p><strong>Special cases<\/strong><\/p>\n<p>To maintain blood levels of calcium, therapeutic vitamin D doses are sometimes administered (up to 100,000\u00a0IU or 2.5\u00a0mg daily) to patients who have had their\u00a0parathyroid glands\u00a0removed (most commonly\u00a0kidney dialysis\u00a0patients who have had\u00a0tertiary hyperparathyroidism, but also to patients with\u00a0primary hyperparathyroidism) or with\u00a0hypoparathyroidism.<sup>[72]<\/sup>\u00a0Patients with chronic\u00a0liver disease\u00a0or\u00a0intestinal malabsorption\u00a0disorders may also require larger doses of vitamin D (up to 40,000\u00a0IU or 1\u00a0mg (1000\u00a0micrograms) daily).<\/p>\n<p>Bioavailability<\/p>\n<p>Not all D3 deficiencies can be effectively supplemented or treated with\u00a0vitamin D3 on their own. Older people or those with fatty liver\u00a0or\u00a0metabolic syndrome\u00a0have a reduced ability to absorb vitamin D3. In addition, in\u00a0overweight\u00a0or\u00a0obese\u00a0persons, excessive\u00a0adipose tissue can sequester D3 from circulation and reduce its access to other tissues.\u00a0With age or obesity, metabolic activation of D3 may be reduced by liver\u00a0steatosis\u00a0or by\u00a0microbiome\u00a0imbalance.<\/p>\n<p>For vitamin D3 to perform its hormonal roles, it is converted into its biologically active metabolite,\u00a0calcifediol, or 25-hydroxyvitamin D3, an activation occurring by a\u00a0hydroxylation reaction in the liver, the cytochrome P450 system, and the gut microbiome.<\/p>\n<p>Epidemiology<\/p>\n<p>The estimated population with a vitamin D deficiency varies based on the threshold used to define a deficiency.<\/p>\n<table>\n<tbody>\n<tr>\n<td><strong>Percentage of US population<\/strong><\/td>\n<td><strong>Definition of insufficiency<\/strong><\/td>\n<td><strong>Study<\/strong><\/td>\n<td><strong>Reference<\/strong><\/td>\n<\/tr>\n<tr>\n<td>69.5%<\/td>\n<td>25(OH)D less than 30\u00a0ng\/mL<\/td>\n<td>Chowdhury <em>et al.<\/em>\u00a02014<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>77%<\/td>\n<td>25(OH)D less than 30\u00a0ng\/mL<\/td>\n<td>Ginde\u00a0<em>et al.<\/em>\u00a02009<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>36%<\/td>\n<td>25(OH)D less than 20\u00a0ng\/mL<\/td>\n<td>Ginde\u00a0<em>et al.<\/em>\u00a02009<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>6%<\/td>\n<td>25(OH)D less than 10\u00a0ng\/mL<\/td>\n<td>Ginde\u00a0<em>et al.<\/em>\u00a02009<\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Recommendations for 25(OH)D serum levels vary across authorities and probably vary based on factors like age; calculations for the epidemiology of vitamin D deficiency depend on the recommended level used.<\/p>\n<p>A 2011\u00a0Institute of Medicine (IOM) report set the sufficiency level at 20\u00a0ng\/ml (50 nmol\/l), while in the same year,\u00a0The Endocrine Society defined sufficient serum levels at 30 ng\/ml, and others have set the level as high as 60 ng\/ml. As of 2011, most reference labs used the 30 ng\/ml standard.<\/p>\n<p>Applying the IOM standard to\u00a0NHANES data on serum levels, for the period from 1988 to 1994, 22% of the US population was deficient, and 36% were deficient for the period between 2001 and 2004; applying the Endocrine Society standard, 55% of the US population was deficient between 1988 and 1994, and 77% were deficient for the period between 2001 and 2004.<\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\" wp-image-8672 aligncenter\" src=\"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/images-2-1.jpg?resize=419%2C279&#038;ssl=1\" alt=\"Vitamin-D-Deficiency\" width=\"419\" height=\"279\" \/><\/p>\n<p>In 2011 the\u00a0Centers for Disease Control and Prevention applied the IOM standard to NHANES data on serum levels collected between 2001 and 2006. They determined that 32% of Americans were deficient during that period (8% at risk of deficiency, and 24% at risk of inadequacy).<\/p>\n<p><strong>History<\/strong><\/p>\n<p>Edward Mellanby, between 1918 and 1920, determined the role of diet in the development of rickets. In 1921, Elmer McCollum\u00a0identified an\u00a0antirachitic\u00a0substance found in certain fats that could prevent rickets. Because the newly discovered substance was the fourth vitamin identified, it was called vitamin D. The 1928 Nobel Prize in Chemistry was awarded to\u00a0Adolf Windaus, who discovered the steroid\u00a07-dehydrocholesterol, the precursor of vitamin D.<\/p>\n<p>Before the fortification of milk products with vitamin D, rickets were a major public health problem. In the United States, milk has been fortified with 10 micrograms (400 IU) of vitamin D per\u00a0quart\u00a0since the 1930s, leading to a dramatic decline in the number of rickets cases.<\/p>\n<p><strong>Research<\/strong><\/p>\n<p>Some evidence suggests vitamin D deficiency may be associated with a worse outcome for some\u00a0cancers. Still, the\u00a0evidence is insufficient to recommend that vitamin D be prescribed for people with cancer. Taking vitamin D supplements has no significant effect on cancer risk. Vitamin D<sub>3<\/sub>, however, appears to decrease the risk of death from cancer but concerns with the quality of the data exist.<\/p>\n<p>Vitamin D deficiency is thought to play a role in the pathogenesis of non-alcoholic fatty liver disease.<\/p>\n<p>Evidence suggests that vitamin D deficiency may be associated with impaired immune function.\u00a0Those with vitamin D deficiency may have trouble fighting off certain types of infections. It has also been thought to correlate with\u00a0cardiovascular disease,\u00a0type 1 diabetes,\u00a0type 2 diabetes, and some cancers.<\/p>\n<p>Review studies have also seen associations between vitamin D deficiency and\u00a0pre-eclampsia.<\/p>\n<blockquote class=\"wp-embedded-content\" data-secret=\"WK6snyjajD\"><p><a href=\"https:\/\/www.diabetesasia.org\/hindimagazine\/%e0%a4%b5%e0%a4%bf%e0%a4%9f%e0%a4%be%e0%a4%ae%e0%a4%bf%e0%a4%a8-%e0%a4%a1%e0%a5%80-%e0%a4%95%e0%a5%80-%e0%a4%95%e0%a4%ae%e0%a5%80\/\">\u0935\u093f\u091f\u093e\u092e\u093f\u0928 \u0921\u0940 \u0915\u0940 \u0915\u092e\u0940<\/a><\/p><\/blockquote>\n<p><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&#8220;\u0935\u093f\u091f\u093e\u092e\u093f\u0928 \u0921\u0940 \u0915\u0940 \u0915\u092e\u0940&#8221; &#8212; Diabetes Asia Health Magazine in Hindi\" src=\"https:\/\/www.diabetesasia.org\/hindimagazine\/%e0%a4%b5%e0%a4%bf%e0%a4%9f%e0%a4%be%e0%a4%ae%e0%a4%bf%e0%a4%a8-%e0%a4%a1%e0%a5%80-%e0%a4%95%e0%a5%80-%e0%a4%95%e0%a4%ae%e0%a5%80\/embed\/#?secret=WjvQtZmopM#?secret=WK6snyjajD\" data-secret=\"WK6snyjajD\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Vitamin D deficiency\u00a0or\u00a0hypovitaminosis D is defined as a vitamin D level that is below normal&#8230;.<\/p>\n","protected":false},"author":2,"featured_media":1292,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[23,27,875],"tags":[1730,645],"class_list":["post-1291","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-lifestyle-medicine","category-nutrioin-in-disease","category-women-health","tag-hypovitaminosis-d","tag-vitamin-d-deficiency"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.diabetesasia.org\/magazine\/wp-content\/uploads\/2021\/07\/Vitamin-D.jpg?fit=176%2C266&ssl=1","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/posts\/1291","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/comments?post=1291"}],"version-history":[{"count":6,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/posts\/1291\/revisions"}],"predecessor-version":[{"id":8674,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/posts\/1291\/revisions\/8674"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/media\/1292"}],"wp:attachment":[{"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/media?parent=1291"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/categories?post=1291"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.diabetesasia.org\/magazine\/wp-json\/wp\/v2\/tags?post=1291"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}