vitamin D - Cholecalciferol

[annelb]

I have put some of the info from OBT about vitamin D on the Vitamin forum. Thought more people might read it that way. Here is the link http://brain.hastypastry.net/forums/showthread.php?t=2822

Most of us are deficient in vitamin D - winter is coming. Do you know what your vitamin D level is?

Anne

[annelb]

It may be very important, as flu season decends on us, to get our vitamin D levels to optimal numbers. The complete article is available.

Epidemic influenza and vitamin D
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=469543
Abstract

In 1981, R. Edgar Hope-Simpson proposed that a ‘seasonal stimulus’ intimately associated with solar radiation explained the remarkable seasonality of epidemic influenza. Solar radiation triggers robust seasonal vitamin D production in the skin; vitamin D deficiency is common in the winter, and activated vitamin D, 1,25(OH)2D, a steroid hormone, has profound effects on human immunity. 1,25(OH)2D acts as an immune system modulator, preventing excessive expression of inflammatory cytokines and increasing the ‘oxidative burst’ potential of macrophages. Perhaps most importantly, it dramatically stimulates the expression of potent anti-microbial peptides, which exist in neutrophils, monocytes, natural killer cells, and in epithelial cells lining the respiratory tract where they play a major role in protecting the lung from infection. Volunteers inoculated with live attenuated influenza virus are more likely to develop fever and serological evidence of an immune response in the winter. Vitamin D deficiency predisposes children to respiratory infections. Ultraviolet radiation (either from artificial sources or from sunlight) reduces the incidence of viral respiratory infections, as does cod liver oil (which contains vitamin D). An interventional study showed that vitamin D reduces the incidence of respiratory infections in children. We conclude that vitamin D, or lack of it, may be Hope-Simpson's ‘seasonal stimulus’.
Anne

[canoe]

I have put some of the info from OBT about vitamin D on the Vitamin forum. Thought more people might read it that way. Here is the link http://brain.hastypastry.net/forums/showthread.php?t=2822

Most of us are deficient in vitamin D - winter is coming. Do you know what your vitamin D level is?

Anne

Dear Anne,

Just an update re: Vit D levels. You might remember that in August my Vit D level (25 OH) was 24, normal 20-100 ng/mL, even though I had been taking supplements in the amount of 1200-1600 IU every day for more than a year.

I just had a repeat Vit D 25 OH level redrawn after almost 3 months on a liquid Vit D emulsion and my level is now up to 50 and I am delighted. This year's Dexa also showed that I am stable even though my Vit D had been down. Actually had an increase in the LS spine results.

I am going to continue with the Vit D emulsion at doses of 2000-4000 IU a day.

Thanks for all the information on Vit D. I have found it very helpful.

Marilyn

[annelb]

good to hear that your vitamin D is now in the optimal range. I have heard that 2000 IU is safe but I don't know about levels higher than that. Do get your level checked again. Interesting the difference from a change in supplement. Were they both D3?
Anne

[canoe]

Dear Anne,

Yes, all of the Vit D that I had previously been taking was D3 and I was taking with food to increase absorption. One of my docs said that she had read that up to 5000 IU was okay, but the Vit D article on the osteoporosis site would seem to indicate differently. See below.

Vitamin D
Vitamin D metabolism Vitamin D levels Vitamin D supplements Vitamin D metabolites Disorders of vitamin D

Vitamin D metabolism
Vitamin D is formed in the skin after exposure to ultraviolet radiation and also is absorbed from the diet. It is hydroxylated at the liver to 25-hydroxyvitamin D, and in the kidney to 1,25-dihydroxyvitamin D which is the active form.
Vitamin D levels in serum
25 (OH) D Level ng/ml nMol/L
Deficient less than 8 less than 20
Insufficient 8-20 20-50
Optimal 20-60 50-150
High 60-90 150-225
Toxic greater than 90 greater than 225

Measure 25(OH) vitamin D, not 1,25(OH)2 vitamin D
1,25(OH)2 vitamin D is more difficult and expensive to measure than 25(OH)D; moreover, it is not a good measure of vitamin D status. When patients are vitamin D deficient, the parathyroid hormone increases and drives the renal 1-alpha-hydroxylase, so that 1,25(OH)2 vitamin D levels increase. Only in severe deficiency, when substrate is depleted, does the 1,25(OH)2 vitamin D become low. Partially treated vitamin D deficiency also results in marked elevations of 1,25(OH)2 vitamin D levels.
Vitamin D requirements
There are two sources of vitamin D, natural sunlight and fortification of dietary foods, particulary dairy products and some cereals. The radiation that converts vitamin D in the skin is the same wavelength that causes sunburn, so careful application of sunscreen can inhibit vitamin D production. At northern latitudes, there is not enough radiation to convert vitamin D, especially during the winter. After the age of 70 the skin does not convert vitamin D effectively.

Vitamin D supplementation
People with poor sunlight exposure 400-1000 units/day
Adults older than 70 800-1000 units/day
Patients with cystic fibrosis 800-1000 units/day
Patients with malabsorption Up to 50,000 units/day, check levels
Patients with liver disease May need active metabolites
Patients with kidney disease Need active metabolites
Patients with sarcoidosis Avoid unless very low levels
Many vitamin D supplements also contain high contents of vitamin A - and recent studies show that vitamin A can increase bone resorption. The labels do not have to list the vitamin A, but it is often there, especially if it comes from cod liver oil. The Optimum brand or the Bartells brand have "pure" vitamin D, also called cholecalciferol. It costs about $4.00 for 100 tablets.


What are optimal levels?
The normal values are higher than previously used. The definitions of normal and optimal are still debated. Heaney suggests there are two ways to define the optimal level: that level at which calcium absorption does not change further on giving extra vitamin D, and that level which will avoid increases in parathyroid hormone. Both approaches revealed serum 25(OH)D levels of 32 ng/ml. A survey in a general medical hospital found that 57% of hospitalized patients had levels lower than 15ng/ml. This high prevalence of hypovitaminosis D might contribute to osteoporosis. Excess vitamin D, on the other hand, can accelerate bone resorption. In patients referred to a bone clinic, 4 patients with high 25(OH)D levels (53-89 ng/ml) from dietary supplements had hypercalciuria and osteoporosis, and the bone density improved over 3 years after they stopped their supplements.
Compston, J wrote an editorial in the BMJ about vitamin D intakes, which should be incrased to help prevent osteoporosis. A 1998 study showed a high incidence of low vitamin D in the United States. Thomas, M. K.
Here is a table of studies showing some of the evidence for giving vitamin D.

Active metabolites of vitamin D
Metabolites of vitamin D increase the intestinal absorption of calcium. These steroid hormones have many other cellular effects, such as increasing the differentiation of cells and stimulating pre-osteoclasts. Calcitriol (1,25 (OH)2 vitamin D, the most active metabolite) increases osteocalcin production by osteoblasts and thus has been considered to stimulate bone formation. Several studies, however, have shown that calcitriol does not increase the bone formation rate measured directly from bone biopsies.
Active metabolites of vitamin D have been advocated for treatment of osteoporosis. A common misunderstanding is that calcitriol has a dose-dependent effect on bone mass. Studies of populations with vitamin D deficiency or poor calcium nutrition show improvement in bone mass, but this is not seen in women who are well nourished. In the U.S. three studies of calcitriol all showed no significant increase in bone mass compared to baseline, although the two smaller studies showed the calcitriol group had better change in bone density than the placebo group in some skeletal areas. Researchers from New Zealand concluded that calcitriol treatment reduced the rate of vertebral fractures. This unblinded study had a 30% drop-out rate which might have biased the results. Bone mass was not measured.
Here is a table of clinical trials using calcitriol for postmenopausal osteoporosis
This graph shows controlled trials that reported bone density in each group. The results of the controls are plotted vs the results of the treated subjects, so that the points that fall ABOVE the diagonal line represent studies in which the treatment group was BETTER than the control group. The size of the point is proportional to the nubmer of subjects in the study.
Calcitriol is not a benign drug. Virtually every study has shown dramatic increases in the urine calcium levels. Long-term use could potentially be damaging to the kidney. The early studies of calcitriol or 1a-hydroxy vitamin D are replete with examples of serious hypercalcemia, some requiring hospitalization.
Calcitriol should not be recommended for the patient with idiopathic postmenopausal osteoporosis because it does not usually improve bone mass in patients who have adequate calcium and vitamin D levels, and because it has an unacceptable risk/benefit ratio. Hypercalcemia and hypercalciuria are frequently reported. However, calcitriol is beneficial in patients who have mild intestinal malabsorption, and may be a useful adjuvant therapy in cases of steroid-induced osteoporosis. In cases of moderate renal failure with evidence of parathyroid stimulation, calcitriol can prevent the development of "tertiary" hyperparathyroidism. These patients must be monitored carefully, with attention paid to the calcium intake and the urine calcium.
Vitamin D disorders
High levels of vitamin D are usually iatrogenic, resulting in hypercalcemia and/or hypercalciuria. Some patients with kidney stones have slightly high 1,25 (OH)2D levels, with increased intestinal absorption of calcium but normal serum calcium. Granulomatous diseases or lymphomas may also produce excess 1,25 (OH)2D, and patients with primary hyperparathryoidism have slightly increased levels.
Vitamin D deficiency is seen in patients with inadequate sunlight exposure who also ingest inadequate amounts of vitamin D. Examples are nursing home patients, breast-fed babies who don't get outside, Arabian women who move to London. Patients with malabsorption also may have vitamin D deficiency.
Liver disease can result in low levels of 25-hydroxy-vitamin D, but usually this does not happen until end-stage liver failure. Renal disease results in decreased levels of 1,25 (OH)2D. The levels gradually decrease in parallel to decreases in renal function, and by the time patients require dialysis they virtually always have calcium abnormalities.
A very rare but fascinating disorder is oncogenic osteomalacia, in which a mesenchymal tumor secretes a factor ("phosphatonin", which is FGF23 in many cases) which acts on the renal tubule to inhibit vitamin D and to increase urine phosphate loss. Other rare disorders include inborn errors of metabolism, such as lack of vitamin D receptor (Vitamin D resistance) or lack of the renal 1-alpha-hydroxylase.
These deficiency disorders may all eventually cause osteomalacia. Photomicrographs of osteomalacia and secondary hyperparathryoidism caused by renal failure can be found in the gallery.

Marilyn

[annelb]

There is evidence of that MS is associated with low vitamin D levels. If you are more comfortable looking at vitamin D as ng/ml then you need to divide the levels in the abstract by 2.6.
Anne

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17179460&query_hl=8&itool=pubmed_docsum
: JAMA. 2006 Dec 20;296(23):2832-8. Links
Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis.Munger KL, Levin LI, Hollis BW, Howard NS, Ascherio A.
Department of Nutrition, Harvard School of Public Health, and Channing Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass 02115, USA.

CONTEXT: Epidemiological and experimental evidence suggests that high levels of vitamin D, a potent immunomodulator, may decrease the risk of multiple sclerosis. There are no prospective studies addressing this hypothesis. OBJECTIVE: To examine whether levels of 25-hydroxyvitamin D are associated with risk of multiple sclerosis. DESIGN, SETTING, AND PARTICIPANTS: Prospective, nested case-control study among more than 7 million US military personnel who have serum samples stored in the Department of Defense Serum Repository. Multiple sclerosis cases were identified through Army and Navy physical disability databases for 1992 through 2004, and diagnoses were confirmed by medical record review. Each case (n = 257) was matched to 2 controls by age, sex, race/ethnicity, and dates of blood collection. Vitamin D status was estimated by averaging 25-hydroxyvitamin D levels of 2 or more serum samples collected before the date of initial multiple sclerosis symptoms. MAIN OUTCOME MEASURES: Odds ratios of multiple sclerosis associated with continuous or categorical levels (quantiles or a priori-defined categories) of serum 25-hydroxyvitamin D within each racial/ethnic group. RESULTS: Among whites (148 cases, 296 controls), the risk of multiple sclerosis significantly decreased with increasing levels of 25-hydroxyvitamin D (odds ratio [OR] for a 50-nmol/L increase in 25-hydroxyvitamin D, 0.59; 95% confidence interval, 0.36-0.97). In categorical analyses using the lowest quintile (<63.3 nmol/L) as the reference, the ORs for each subsequent quintile were 0.57, 0.57, 0.74, and 0.38 (P = .02 for trend across quintiles). Only the OR for the highest quintile, corresponding to 25-hydroxyvitamin D levels higher than 99.1 nmol/L, was significantly different from 1.00 (OR, 0.38; 95% confidence interval, 0.19-0.75; P = .006). The inverse relation with multiple sclerosis risk was particularly strong for 25-hydroxyvitamin D levels measured before age 20 years. Among blacks and Hispanics (109 cases, 218 controls), who had lower 25-hydroxyvitamin D levels than whites, no significant associations between vitamin D and multiple sclerosis risk were found. CONCLUSION: The results of our study suggest that high circulating levels of vitamin D are associated with a lower risk of multiple sclerosis.

PMID: 17179460 [PubMed - in process]

[NancyM]

I just had a repeat Vit D 25 OH level redrawn after almost 3 months on a liquid Vit D emulsion and my level is now up to 50 and I am delighted. This year's Dexa also showed that I am stable even though my Vit D had been down. Actually had an increase in the LS spine results.

I've read that 50 is ideal. This whole Vit. D thing is SO complicated. If you take too much you could end up with calcium deposits in bad places (like the heart). If you have too little you can end up with cancer. Argh!
Testing Vitamin D Levels

All people must make a personal decision whether or not to test their vitamin D levels based on the amount of vitamin D they are consuming, their own perception of its risk, and any concern they may have that they are not consuming enough. If you choose to test your vitamin D level, there are several things to keep in mind:

* Order the calcidiol test, not the calcitriol test. The correct test is also called 25-hydroxyvitamin D or 25 (OH) D
* The laboratory's reference range is likely to use a very wide definition of "normal." Sufficient levels of vitamin D are at least 32 ng/mL, and ideal levels are probably between 40 and 50 ng/mL.
* Your vitamin D levels will rise over the spring and summer and decline over the fall and winter. Your vitamin D level during one season will therefore not necessarily reflect your vitamin D level for other seasons.
* The scientific data does not clearly and consistently define an ideal level of vitamin D, and we do not know to what degree intakes of other nutrients affect what constitutes the ideal level.


I skimmed this, it made my eyes cross: http://www.westonaprice.org/basicnutrition/vitamin-d-safety.html

I get virtually no sunlight because I'm on a drug that makes me photosensitive. So I am currently taking 2000-4000 iu a day. Depending on what I've read recently. :p