Vitamin D also called the “sunshine vitamin” helps protect the skin, prevent respiratory tract infections, treat rheumatoid arthritis, prevent hair loss and has a positive effect on male fertility.
- Vitamin D Two Part Series
- Health Benefits of Vitamin D
- 20) Vitamin D is Beneficial in Atopic Dermatitis
- 21) Vitamin D is Effective Therapy for Psoriasis Patients
- 22) Vitamin D May Benefit Thyroid Dysfunction
- 23) Vitamin D Reduces Severity of Asthma
- 24) Vitamin D Affects Chronic Obstructive Pulmonary Disease
- 25) Vitamin D Reduces Risk of Tuberculosis
- 26) Vitamin D has Negative Effect on Sarcoidosis
- 27) Vitamin D Decreases the Risk of Respiratory Tract Infections
- 28) Vitamin D Plays a Role in Systemic Lupus Erythematosus
- 29) Vitamin D is Beneficial in Rheumatoid Arthritis
- 30) Vitamin D Protects Kidney Function
- 31) Vitamin D is Beneficial in HIV Disease
- 32) Vitamin D Affects Male Fertility
- 33) Vitamin D is Beneficial in Pregnancy and Lactation
- 34) Vitamin D Improves Clinical Manifestations of Polycystic Ovary Syndrome
- 35) Vitamin D Influences Hair Loss
Vitamin D Two Part Series
- Vitamin D benefits 1-19 (Part 1)
- Vitamin D benefits 20-35 (Part 2)
Health Benefits of Vitamin D
20) Vitamin D is Beneficial in Atopic Dermatitis
Atopic dermatitis affects up to 20% of children and up to 3% of adults (R).
Vitamin D deficiency could be associated with the prevalence of atopic dermatitis (R).
Vitamin supplementation may improve disease symptoms and severity.
21) Vitamin D is Effective Therapy for Psoriasis Patients
A daily dose of 35,000 IU of this vitamin is a safe and effective therapy for psoriasis patients (R).
Topical vitamins calcipotriol and/or tacalcitol are considered as first-line treatment for mild-to-moderate psoriasis.
22) Vitamin D May Benefit Thyroid Dysfunction
Deficiency may exacerbate the onset and/or development of Graves’ disease
Correction of the deficiency may be able to reverse it (R).
Vitamin D deficiency severity was associated with duration of the disease, thyroid gland size, and antibody levels (R).
23) Vitamin D Reduces Severity of Asthma
Lower vitamin levels are associated with increased markers of allergy and asthma severity (R).
24) Vitamin D Affects Chronic Obstructive Pulmonary Disease
Lower blood vitamin levels were associated with a higher risk of COPD (R).
Its deficiency is associated with increased risk of lung infections, causing worsening of COPD (R).
Vitamin D regulates airway contraction and inflammation (R).
25) Vitamin D Reduces Risk of Tuberculosis
Blood levels of this vitamin are lower in tuberculosis patients comparing to healthy individuals (R).
26) Vitamin D has Negative Effect on Sarcoidosis
Increased level of this vitamin is associated with disease activity (R).
Elevated vitamin levels require chronic immunosuppressive therapy in patients with sarcidosis (R).
Patients with sarcoidosis do not benefit from vitamin D supplementation (R).
27) Vitamin D Decreases the Risk of Respiratory Tract Infections
Lower levels of vitamin D are related to increased risk of respiratory infections (R).
Studies showed a decrease in respiratory tract infections in children taking 600 to 700 IU/d vitamin D supplementation (R).
Supplementation with 1200 IU/d prevents against influenza A in school children between December and March (R).
Supplementation with this vitamin (at 300 IU daily) significantly reduced the risk of acute respiratory infections by 50% among Mongolian children with vitamin D deficiency in winter (R).
However, a monthly dose of 100 000 IU of vitamin D in healthy adults did not significantly reduce the incidence or severity of upper respiratory tract infections (R).
28) Vitamin D Plays a Role in Systemic Lupus Erythematosus
Systemic lupus erythematosus (SLE) activity is associated with lower vitamin D blood levels (R).
Vitamin D supplementation has an effect on immune system in patients with SLE.
It decreases memory B cells, effector Th1 and Th17 cells, and increases Tregs (R).
29) Vitamin D is Beneficial in Rheumatoid Arthritis
Vitamin D supplementation suppresses Th17 cell cytokines and has the effect potential to treat patients with RA (R).
Vitamin D deficiency is present in 30-63% of people with rheumatoid arthritis (R).
Greater intake of vitamin D may be associated with a lower risk of rheumatoid arthritis in older women (R).
Low blood levels are associated with rheumatoid arthritis symptoms and severity.
Supplementation of 500 IU/day to patients with early rheumatoid arthritis along with anti-rheumatic therapy results in higher pain relief (R).
30) Vitamin D Protects Kidney Function
Chronic kidney disease patients have a higher prevalence of vitamin D deficiency compared to the general population (R).
Vitamin D deficiency or insufficiency is frequent after renal transplantation (R).
The VITALE study (VITamin D supplementation in renAL transplant recipients) showed that high doses of vitamin D prevent posttransplant bone loss without causing adverse events (R).
It can protect kidney from injury in patients with diabetic kidney disease (R).
31) Vitamin D is Beneficial in HIV Disease
Vitamin D deficiency is common among individuals infected with human immunodeficiency virus (HIV).
HIV-infected patients with abnormally low vitamin D levels had shorter survival than other HIV-infected subjects (R).
This vitamin improves HIV-associated immunity.
High doses of vitamin D supplementation decreases virus production, and increases white blood cells (R).
32) Vitamin D Affects Male Fertility
Studies on mice show beneficial effects of vitamin D on male reproductive system (R).
Male mice who lack vitamin D receptors suffer from infertility.
Vitamin D is important for sperm production, growth, and survival (R).
Blood levels of this vitamin are associated with sperm motility.
Men with vitamin D deficiency (blood levels <20 ng/mL) had less motile sperm compared with men with high levels.
Also, blood levels above 50 ng/mL were associated with decreased sperm production and quality.
33) Vitamin D is Beneficial in Pregnancy and Lactation
Vitamin D deficiency was high in a diverse group of women during pregnancy, affecting 97% of African Americans, 81% of Hispanics, and 67% of Caucasians.
Its deficiency in pregnant women may affect both the women and newborns.
Vitamin D sufficiency may protect from spontaneous preterm birth risk (R).
Vitamin D deficiency during pregnancy is associated with:
- An increased risk of preeclampsia, the leading cause of maternal and neonatal morbidity and mortality (R, R2).
- Almost 4 times the odds of primary cesarean section (R).
- Bacterial vaginosis, a highly prevalent vaginal infection that is associated with adverse pregnancy outcomes (R).
Vitamin D supplementation of 4000 IU/day for pregnant women is safe, effective in achieving sufficiency in all women and their newborns, and associated with fewer adverse events of pregnancy (R).
It was thought for decades that breast milk was ‘naturally’ low in vitamin D.
Since vitamin D is transferred into the milk, the mother needs a daily source of vitamin D in order to provide her infant with enough substrate to avoid deficiency (R).
An intake of 6400 IU/day of vitamin D provides enough vitamin D to a breastfeeding infant (R).
34) Vitamin D Improves Clinical Manifestations of Polycystic Ovary Syndrome
Women with polycystic ovary syndrome (PCOS) have low vitamin D blood levels
PCOS is accompanied by a high risk of cardiovascular diseases.
Low-dose vitamin D is used as an additional therapy for PCOS and cardiovascular diseases (R).
35) Vitamin D Influences Hair Loss
Studies show an important role of vitamin D receptor in hair loss (R).
The function of vitamin D receptor is essential for maintenance of normal hair cycle.
Screening patients with hair loss for vitamin D deficiencies seems to be of value for the possibility of supplementing these patients with vitamin D.
Supplementation may be useful to grow hair in case of its deficiency (R).
There are two forms of vitamin D: vitamin D2 and vitamin D3.
Vitamin D2 (ergocalciferol) is produced in plants, fungi, and yeasts.
Vitamin D3 (cholecalciferol) is synthesized in the skin and consumed in animal-based foods (R).
Both forms of vitamin D are biologically inactive and must activated in the body.
In the liver, vitamin D is converted to calcidiol (25-hydroxyvitamin D [25(OH)D]), the major circulating form of vitamin D, and the indicator of vitamin D status (R).
In the kidneys, calcidiol is converted to calcitriol (1,25-dihydroxyvitamin D [1,25(OH)2D]), the active form of vitamin D (R).
In order to regulate bodily functions, calcitriol binds to vitamin D receptor (VDR) in the cytoplasm of target cells, and goes to the nucleus and binds with the retinoic acid X receptor (RXR).
This complex regulates the expression of vitamin D regulated genes (R).
Vitamin D taken orally is absorbed in the gut with the aid of bile salts.
It is transported to blood by chylomicrons, and taken up by the liver or storage tissues (fat tissue and skeletal muscles) (R).
There are many factors that affect vitamin D absorption resulting in large differences in the bioavailability of vitamin D supplements in some populations (R).
Also, individuals taking medications that bind bile acid (such as cholestyramine) will also have impaired vitamin D absorption (R).
Obesity is also associated with decreased vitamin D levels (R).
Vitamin D is most efficiently absorbed when consumed with food containing fat.
Taking vitamin D with the largest meal improves absorption, and results in a 50% increase in blood levels of vitamin D (R).
Very few foods in nature contain vitamin D.
Major food sources are fatty fish (salmon, tuna, mackerel), cod liver oil, beef liver, egg yolks, cheese, and mushrooms (shiitake, portabella) (R).
Some foods are fortified with vitamin D. These include milk, soy milk, yogurt, margarine, orange juice, and cereals (R).
Both the United States and Canada mandate the fortification of infant formula with vitamin D: 40–100 IU/100 kcal in the United States and 40–80 IU/100 kcal in Canada (R).
In supplements, vitamin D is available in two forms, D2 (ergocalciferol) and D3 (cholecalciferol) (R).
Vitamin D3 is approximately 87% more effective in raising and maintaining the vitamin D levels in the body than vitamin D2.
Most multivitamins contain 400 IU of vitamin D, and single ingredient vitamin D supplements are available for additional supplementation.
Intake of ordinary doses of vitamin D3 supplements seems to be associated with decreases in overall risk of dying (R).
Most of the vitamin D3 in humans is derived from the synthesis in the skin.
Children 1 yr and older and adolescents should have a daily intake of 600 IU of vitamin D.
Adults aged 19–70 and over 70 yr require at least 600 and 800 IU/d, respectively, of vitamin D to maximize bone health and muscle function, and prevent falls and fractures.
Pregnant and lactating women require at least 600 IU/d of vitamin D.
Obese and children and adults on anticonvulsant medications, glucocorticoids, antifungals, and medications for AIDS should be given at least two to three times more vitamin D for their age group to satisfy their body’s vitamin D requirement.
Vitamin D deficiency is the most common nutritional deficiency worldwide in both children and adults.
The blood level of 25(OH)D is the best method to determine vitamin D status (R).
Studies suggest that blood 25(OH)D levels between 30 ng/mL and 60 ng/mL are associated with lower risks of adverse health outcomes, including cardiovascular disease, cancers and autoimmune diseases (R).
Causes of vitamin D deficiency:
- Inadequate sun exposure
- Geographical locations (latitude and altitudes), atmospheric conditions (air pollution, the presence of clouds), and seasonal changes influence the intensity of UVB radiation and thus vitamin D production in skin (R).
- People with a dark skin, African Americans and Hispanic Americans. Higher skin melanin content reduces the skin’s ability to make vitamin D (R, R2).
- Wearing protective clothing and hats, and applying sunscreens, reduce skin exposure to sunlight (R, R2, R3).
- Women in the Middle East and North Africa who wear a headscarf or cover all skin. 96% had blood vitamin D levels less than 20 ng/mL, and 60% had vitamin D levels below 12 ng/mL (R, R2).
- Malabsorption of vitamin D
- Patients with gut disease including Crohn’s disease, ulcerous colitis, celiac disease, cystic fibrosis (R, R2, R3).
- Cholestatic and non-cholestatic liver disease (R).
- Low vitamin D intake
- Low vitamin D diet without fortified food or supplements (R).
- Strict vegan diet (R).
- Chronic kidney disease, leads to reduced synthesis of 1,25-dihydroxyvitamin D and an increased loss of 25-hydroxyvitamin D in urine (R).
- Obesity (R).
- The elderly have reduced capacity to synthesize vitamin D in the skin and are more likely to stay indoors or use sunscreen (R, R2).
- Pregnant women (R).
- Infants who are exclusively breastfed and do not receive vitamin D supplementation (R).
- Medication: glucocorticoids, antiepileptic drugs, rifampin, antiretroviral therapy (R).
People who are vitamin D deficient may not have any symptoms at all or symptoms may be vague.
Vitamin D deficiency manifests as fatigue, symmetric low back pain, throbbing bone pain, muscle weakness and aches, sweating, digestive problems, obesity, mood swings, and impaired immunity.
Vitamin D toxicity is extremely rare but potentially serious condition.
It occurs from high intakes of supplements (>50,000 IU/d) for long period of time.
Toxicity does not occur from dietary intake or prolonged sun exposure (R).
Vitamin D is a fat soluble vitamin, and it is stored in fat tissues. Therefore, toxic effects may last for months after stopping supplementation (R).
Vitamin D supplementation must be considered carefully in patients with granulomatous diseases such as sarcoidosis and Crohn’s disease (active phase), metastatic bone disease, and Williams syndrome (infantile hypercalcemia) (R, R2, R3, R4).
The information on this website has not been evaluated by the Food & Drug Administration or any other medical body. We do not aim to diagnose, treat, cure or prevent any illness or disease. Information is shared for educational purposes only. You must consult your doctor before acting on any content on this website, especially if you are pregnant, nursing, taking medication, or have a medical condition.
HOW WOULD YOU RATE THIS ARTICLE?