Hmm, this approach to mega dosing with Vitamin D was abandoned in Australia due to excess morbidity. http://content.time.com/time/health/article/0,8599,1988891,00.html You can google for the original paper.
Looks like the Mega dosing q2months didnt work for reducing asthma / ARTI in vitamin D deficient 48 year olds on steroid puffers. As discussed previously, it could have been the 120,000 IU q2months vs. a daily dose issue or that supplementing vitamin D in 48yo asthmatics isn't important. Side Note: I enjoyed reading this take on the ambiguity of "Vitamin D" http://www.direct-ms.org/pdf/VitDVieth/Vit D not a Hormone Vieth.pdf
Study shows higher levels of vitamin D corresponds to lower cancer risk If you want to lower your risk of cancer, you may want to safely soak up the sun or start taking a supplement you probably already have in your cupboard. According to researchers at University of California, San Diego School of Medicine higher levels of vitamin D, specifically serum 25-hydroxyvitamin D, are associated with a correspondingly reduced risk of cancer. "We have quantitated the ability of adequate amounts of vitamin D to prevent all types of invasive cancer combined,” said Dr. Cedric Garland, with the UC San Diego School of Medicine Department of Family Medicine and Public Health, in a statement. Garland and his late brother, Frank, were the first to connect vitamin D deficiency and some cancers in 1980. That’s when they noted populations at higher latitudes were more likely to get colon cancer because they have less available sunlight and are therefore more deficient in vitamin D, which is produced by the body through sun exposure. They later determined vitamin D links to other cancers, such as breast, lung and bladder. The new study sought to determine what blood level of vitamin D was required to effectively reduce cancer risk. The researchers analyzed two groups of over 1,000 women. Women with 40 ng/ml or greater of the specific type of vitamin D had a 67 per cent lower risk of cancer than women with levels of 20 ng/ml or less. In the past, other scientists have argued whether a target of 20 ng/ml or 50 ng/ml of vitamin D should be the target. Garland does not identify an optimum daily intake of vitamin D or whether it’s best to get it from sun exposure, diet or supplements. Note: 125 nmol/L = 50 ng/ml http://health.ucsd.edu/news/releases/Pages/2016-04-06-low-vitamin-d-higher-cancer-risk.aspx http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0152441 plos1 Serum 25-Hydroxyvitamin D Concentrations =40 ng/ml Are Associated with >65% Lower Cancer Risk: Pooled Analysis of Randomized Trial and Prospective Cohort Study Background Higher serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with a lower risk of multiple cancer types across a range of 25(OH)D concentrations. Objectives To investigate whether the previously reported inverse association between 25(OH)D and cancer risk could be replicated, and if a 25(OH)D response region could be identified among women aged 55 years and older across a broad range of 25(OH)D concentrations. Methods Data from two cohorts representing different median 25(OH)D concentrations were pooled to afford a broader range of 25(OH)D concentrations than either cohort alone: the Lappe cohort (N = 1,169), a randomized clinical trial cohort (median 25(OH)D = 30 ng/ml) and the GrassrootsHealth cohort (N = 1,135), a prospective cohort (median 25(OH)D = 48 ng/ml). Cancer incidence over a multi-year period (median: 3.9 years) was compared according to 25(OH)D concentration. Kaplan-Meier plots were developed and the association between 25(OH)D and cancer risk was examined with multivariate Cox regression using multiple 25(OH)D measurements and spline functions. The study included all invasive cancers excluding skin cancer. Results Age-adjusted cancer incidence across the combined cohort (N = 2,304) was 840 cases per 100,000 person-years (1,020 per 100,000 person-years in the Lappe cohort and 722 per 100,000 person-years in the GrassrootsHealth cohort). Incidence was lower at higher concentrations of 25(OH)D. Women with 25(OH)D concentrations =40 ng/ml had a 67% lower risk of cancer than women with concentrations <20 ng/ml (HR = 0.33, 95% CI = 0.12–0.90). Conclusions 25(OH)D concentrations =40 ng/ml were associated with substantial reduction in risk of all invasive cancers combined.
During metabolism, only 10-15 percent of total vitamin D is available in the body to act on target cells, as most are bound to vitamin D binding proteins. Therefore, evaluating whether the proportion of vitamin D that can be used may be important, as only unbound vitamin D, such as bioavailable vitamin D, is available to act on target cells. source: https://www.sciencedaily.com/releases/2016/04/160403152111.htm I guess any protein of a certain size binds to other proteins. Yet, I don't hear about the "bioavailability" of Vitamin D being discussed too often. I'm not sure there is a lab test for it available. or better yet, how often Total Vitamin D is normal and the bioavailable Vitamin D would be low. I think serum Vitamin D already costs $30. Bioavailable Vitamin D sounds expensive
Vitamin D and Heart Function ? (presumably Ejection Fraction). http://www.upi.com/Health_News/2016/04/04/Vitamin-D-boosts-heart-function-in-study/5691459816005/ Vitamin D boosts heart function in study MONDAY, April 4, 2016 -- Regular doses of vitamin D3 may improve heart function in heart failure patients, a new British study suggests. "These findings could make a significant difference to the care of heart failure patients," said study leader Dr. Klaus Witte, from the University of Leeds School of Medicine. "It is the first evidence that vitamin D3 can improve heart function of people with heart muscle weakness -- known as heart failure." The study included more than 160 patients who had pacemakers and/or were receiving blood pressure drugs known as ACE inhibitors or beta blockers. The study participants took either vitamin D or inactive placebo pills once a day for a year. The researchers explained that they avoided using a calcium-based vitamin D supplement, because calcium can cause other problems for heart failure patients. Heart pumping function improved from 26 percent to 34 percent in patients who took vitamin D, while there was no change among those who took the placebo pills, the investigators found. The study was presented Monday at the annual meeting of the American College of Cardiology in Chicago. Research presented at medical meetings is typically considered preliminary until published in a peer-reviewed journal. The researchers suggested that the improvement seen in some of the patients who took vitamin D might reduce their need for an implantable cardioverter defibrillator (ICD). An ICD is a device that detects dangerous heart rhythm problems and delivers a shock to restore a normal heartbeat. "ICDs are expensive and involve an operation. If we can avoid an ICD implant in just a few patients, then that is a boost to patients and [health systems] as a whole," Witte said in a university news release. Heart failure affects about 23 million people worldwide, the study authors said. Notes: (1) sounds too good to be true. (2) looks like previous studies have been contradictory : example. Code: Objectives The aim of this study was to investigate the effect of vitamin D3 on physical performance in patients with heart failure (HF). Background HF is associated with functional decline and frailty. Vitamin D deficiency is associated with loss of muscle strength and poor outcomes in patients with HF. Methods Sixty-four patients participated in a 6-month parallel-design, double-blind randomized controlled trial to test the hypothesis that oral vitamin D3 would improve physical performance. Vitamin D3 50,000 IU or placebo was given weekly; all patients received daily calcium. Patients were included, regardless of ejection fraction, if they had 25 hydroxyvitamin D (25[OH]D) levels ≤37.5 ng/ml. The primary outcome was peak oxygen uptake, and secondary outcomes were 6-min walk distance, timed get up and go, and knee isokinetic muscle strength. Between-group comparisons were made using analysis-of-covariance models that adjusted for baseline measures. Results Patients’ mean age was 65.9 ± 10.4 years, 48% were women, 64% were African American, the mean ejection fraction was 37.6 ± 13.9%, 36% were in New York Heart Association functional class III, and the remainder were in functional class II. At baseline, the vitamin D group’s mean 25(OH)D level was 19.1 ± 9.3 ng/ml and increased to 61.7 ± 20.3 ng/ml; in the placebo group, the mean baseline 25(OH)D level was 17.8 ± 9.0 ng/ml and decreased to 17.4 ± 9.8 ng/ml at 6 months (between-groups p < 0.001). There was no significant change from baseline to 6 months in peak oxygen uptake, 6-min walk distance, timed get up and go, or isokinetic muscle strength. Conclusions Vitamin D3 did not improve physical performance in patients with HF despite a robust increase in serum 25(OH)D levels. Vitamin D repletion in patients with HF should conform to standard adult guidelines for vitamin D supplementation. (A Trial of Vitamin D Therapy in Patients With Heart Failure; NCT01125436) Of course that study did the 50,000 IU/week vs. daily doses.
Those suggestions are probably based on taking a certain amount of vitamin D without checking your levels. Indeed. Isn't the bioavailability of super high ? I just got my lowest vitamin D level ever. The lab said the patient's level was <10.
Bioavailability relates to the level of free D3 which is not measured. Most is bound to Vitamin D binding protein so is inaccessible. There's a short time it's free when it's synthesized in skin, and then transported in the circulation.
I'm not sure that this is true. Sure the kidneys are the main source of transformation of 25OHD3 to 1,25OHD3 but there is also local conversion at the tissue level. So, even patients who are anephric needs 25OHD3 as well as 1,25OHD3.
