“The Need for Vitamin D3 as a Supplement.”
9 August 2008
- Vitamin D2 is the normally
supplied form in most vitamin D supplements on the market.
- It is not as effective as D3
with about only one quarter the effectiveness, particularly for older
people.
- Vitamin D2 is more quickly
cleared from the system than D3.
- Despite the official Recommended Daily
Allowance (RDA), an adult
body uses about 4000IU/day.
- For adults, to raise serum Vitamin D
status by 8-12nmol/L takes 400 IU/day.
- In winter when/if (depending
on latitude) there is little or no sun, an adult needs 4000IU less
possible food sources (perhaps 300 IU/day) and possible supplements
(perhaps 200 IU/day) .
- In summer even in temperate
latitudes, sun exposure should be sufficient for adults unless not
getting any sun exposure at all.
- Vitamin D3 capsules or tables
in small dosages are expensive.
- Inexpensive 5000 IU capsules
of D3 are available.
- In summer take 5000 IU capsules,
spaced so that the average is about 2000 IU/day. Two 5000 IU
capsules every 5 days will average to 2000 IU per day.
- <>In winter, take
5000 IU
capsules every day for five days,, skipping the sixth day. This
will result in an average of 4000 IU per day.
- Be aware that the proposed
new safe upper limit is 10,000IU/day.
- That paper makes it clear that in fact
this is allowing a very generous safety margin as it would take a daily
input of 40,000IU to actually cause harm,
Further reference
material is abstracts from PubMed database
---------------------------------
Am J Clin Nutr. 2008
Apr;87(4):1080S-6S.
Vitamin D deficiency: a worldwide
problem with health consequences.
Holick MF, Chen TC.
Department of Medicine, Boston University School of Medicine, 715
Albany Street, M-1013, Boston, MA 02118, USA. mfholick@bu.edu
Vitamin D deficiency is now recognized as a pandemic. The major cause
of vitamin D deficiency is the lack of appreciation that sun exposure
in moderation is the major source of vitamin D for most humans. Very
few foods naturally contain vitamin D, and foods that are fortified
with vitamin D are often inadequate to satisfy either a child's or an
adult's vitamin D requirement. Vitamin D deficiency causes rickets in
children and will precipitate and exacerbate osteopenia, osteoporosis,
and fractures in adults. Vitamin D deficiency has been associated with
increased risk of common cancers, autoimmune diseases, hypertension,
and infectious diseases. A circulating level of 25-hydroxyvitamin D of
>75 nmol/L, or 30 ng/mL, is required to maximize vitamin D's
beneficial effects for health. In the absence of adequate sun exposure,
at least 800-1000 IU vitamin D3/d may be needed to achieve this in
children and adults. Vitamin D2 may be equally effective for
maintaining circulating concentrations of 25-hydroxyvitamin D when
given in physiologic concentrations.
---------------------------------
The case against ergocalciferol
(vitamin D2) as a vitamin supplement
Lisa A Houghton and Reinhold Vieth
From the School of Nutrition and Dietetics, Acadia University,
Wolfville, Canada (LAH); the Department of Nutritional Sciences,
University of Toronto, Toronto, Canada (RV); and the Mount Sinai
Hospital, Toronto, Canada (RV)
Supplemental vitamin D is available in 2 distinct forms: ergocalciferol
(vitamin D2) and cholecalciferol (vitamin D3). Pharmacopoeias have
officially regarded these 2 forms as equivalent and interchangeable,
yet this presumption of equivalence is based on studies of rickets
prevention in infants conducted 70 y ago. The emergence of
25-hydroxyvitamin D as a measure of vitamin D status provides an
objective, quantitative measure of the biological response to vitamin D
administration. As a result, vitamin D3 has proven to be the more
potent form of vitamin D in all primate species, including humans.
Despite an emerging body of evidence suggesting several plausible
explanations for the greater bioefficacy of vitamin D3, the form of
vitamin D used in major preparations of prescriptions in North America
is vitamin D2. The case that vitamin D2 should no longer be considered
equivalent to vitamin D3 is based on differences in their efficacy at
raising serum 25-hydroxyvitamin D, diminished binding of vitamin D2
metabolites to vitamin D binding protein in plasma, and a
nonphysiologic metabolism and shorter shelf life of vitamin D2. Vitamin
D2, or ergocalciferol, should not be regarded as a nutrient suitable
for supplementation or fortification.
---------------------------------
Nat Clin Pract Rheumatol. 2008
Aug;4(8):404-12. Epub 2008 Jul 1.
Control of autoimmune diseases by the
vitamin D endocrine system.
Adorini L, Penna G.
Intercept Pharmaceuticals, Corciano (Perugia), Italy.
ladorini@interceptpharma.com
1,25-Dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], the biologically active
form of vitamin D(3), is a secosteroid hormone essential for bone and
mineral homeostasis. It regulates the growth and differentiation of
multiple cell types, and displays immunoregulatory and
anti-inflammatory properties. Cells involved in innate and adaptive
immune responses--including macrophages, dendritic cells, T cells and B
cells--express the vitamin D receptor (VDR), and can both produce and
respond to 1,25(OH)(2)D(3). The net effect of the vitamin D system on
the immune response is an enhancement of innate immunity coupled with
multifaceted regulation of adaptive immunity. Epidemiological evidence
indicates a significant association between vitamin D deficiency and an
increased incidence of several autoimmune diseases, and clarification
of the physiological role of endogenous VDR agonists in the regulation
of autoimmune responses will guide the development of pharmacological
VDR agonists for use in the clinic. The antiproliferative,
prodifferentiative, antibacterial, immunomodulatory and
anti-inflammatory properties of synthetic VDR agonists could be
exploited to treat a variety of autoimmune diseases, from rheumatoid
arthritis to systemic lupus erythematosus, and possibly also multiple
sclerosis, type 1 diabetes, inflammatory bowel diseases, and autoimmune
prostatitis.
---------------------------------
Curr Rheumatol Rep. 2008 Aug;10(4):273-80.
The link between vitamin D deficiency
and systemic lupus erythematosus.
Kamen DL, Aranow C.
Division of Rheumatology, Medical University of South Carolina, 96
Jonathan Lucas Street, Suite 912, Charleston, SC 29425, USA.
kamend@musc.edu
Vitamin D deficiency is highly prevalent and is increasingly thought to
be an important risk factor in many diseases that have high morbidity
and mortality, including lupus. Vitamin D is an immunomodulatory
hormone with effects on T cells, B cells, and dendritic cells. Animal
models of autoimmune disease and epidemiologic studies suggest a role
for vitamin D as a modifiable environmental factor in autoimmune
disease. Recommendations are available regarding screening for and
repletion of vitamin D deficiency. More research is needed to
understand the role of vitamin D as an immunomodulator and to determine
the optimal range of serum 25-hydroxyvitamin D for musculoskeletal,
cardiovascular, and immune health.
---------------------------------
Curr Opin Nephrol Hypertens. 2008 Jul;17(4):408-15.
The noncalciotropic actions of vitamin
D: recent clinical developments.
Maalouf NM.
Charles and Jane Pak Center of Mineral Metabolism and Clinical
Research, University of Texas Southwestern Medical Center, Dallas,
Texas 75390-8885, USA. naim.maalouf@utsouthwestern.edu
PURPOSE OF REVIEW: This review summarizes recently described actions of
1,25-dihydroxyvitamin D beyond its function in calcium homeostasis and
bone metabolism. RECENT FINDINGS: 1,25-Dihydroxyvitamin D stimulates
the innate immune system, facilitating the clearance of infections such
as tuberculosis. Hypovitaminosis D has been associated with several
autoimmune disorders, various malignancies, and cardiovascular risk
factors in a number of recent epidemiologic reports. Based on these
observational reports, vitamin D and its analogues are being evaluated
for the prevention and treatment of a variety of conditions, with early
findings showing mixed results. SUMMARY: The broad tissue distribution
of the 25-hydroxyvitamin D 1alpha-hydroxylase enzyme and the vitamin D
receptor establish a role for 1,25-dihydroxyvitamin D in the
pathophysiology of various disease states and provide new therapeutic
targets for vitamin D and its analogues
---------------------------------
Scand J Immunol. 2008 May 29. [Epub ahead of print] Links
The Complex Role of Vitamin D in
Autoimmune Diseases.
Szodoray P, Nakken B, Gaal J, Jonsson R, Szegedi A, Zold E, Szegedi G,
Brun JG, Gesztelyi R, Zeher M, Bodolay E.
Division of Clinical Immunology, 3rd Department of Medicine, Medical
and Health Science Center, University of Debrecen, Debrecen, Hungary.
Vitamin D, besides having well-known control functions of calcium and
phosphorus metabolism, bone formation and mineralization, also has a
role in the maintenance of immune-homeostasis. The immune-regulatory
role of vitamin D affects both the innate and adaptive immune system
contributing to the immune-tolerance of self-structures. Impaired
vitamin D supply/regulation, amongst other factors, leads to the
development of autoimmune processes in animal models of various
autoimmune diseases. The administration of vitamin D in these animals
leads to improvement of immune-mediated symptoms. Moreover, in human
autoimmune diseases, such as multiple sclerosis, or rheumatoid
arthritis the pathogenic role of vitamin D has been described. The
review aims at describing the complex immune-regulatory role of vitamin
D from the cellular level through autoimmune animal models and
depicting the known contribution of vitamin D in the pathogenesis of
human autoimmune diseases..