28 juli 2018: Lees ook dit artikel:

https://kanker-actueel.nl/champignons-bewerkt-met-speciale-belichting-hebben-daarmee-veel-extra-vitamine-d-en-kunnen-vitamine-d-supplementen-vervangen.html

Zie ook dit artikel:

https://kanker-actueel.nl/melanomen-calcium-plus-vitamine-d-voorkomt-voor-57-procent-dat-vrouwen-met-een-geschiedenis-van-een-vorm-van-oppervlakkige-huidkanker-alsnog-een-melanoom-ontwikkelen.html

Zie ook onze literatuurlijsten en zie ook in gerelateerde artikelen

28 juli 2018: Bron: JAMA Oncol. Published online July 19, 2018

Maandelijks een hoge dosis vitamine D zonder extra calcium blijkt niet voldoende om kanker te voorkomen. Dat blijkt uit een Australische studie bij 5100 volwassenen (vitamin D₃ (n = 2558) of placebo (n = 2552))

Eerdere studies hebben wel de waarde aangetoond van preventief vitamine D3 maar dat wordt dan wekelijks of soms zelfs dagelijks gegeven en bijna altijd in combinatie met calcium. En ook werkt vitamine D3 suppletie bij mensen die al kanker hebben. Zo zijn er studies die aantonen dat bv. vrouwen met borstkanker of kankerpatiënten met lymfklierkanker of darmkanker enz. vaak een tekort aan vitamine D hebben / hadden.

Vitamine D mechanisme(2)

Studieresultaten:

In deze recente studie werd eerst oraal vitamin D₃gegeven in een eerste dosis van 200 000 IU gevolgd door maandelijks doses van 100 000 IU, of een placebo over een periode van mediaan 3.3 jaar (range, 2.5-4.2 jaar).

In beide groepen (gemiddelde leeftijd 65,9 jaar) bleken dezelfde aantal mensen kanker te hebben gekregen, hoewel de vitamine D waarden in de vitamine D groep wel wat hoger waren (20 ng/mL hoger) had dit dus geen invloed op het krijgen van kanker gedurende de studieduur: 165 van de 2558 deelnemers (6.5%) in de vitamin D groep en 163 van de 2550 (6.4%) in de placebo groep hadden een diagnsoe van kanker gehad, (an adjusted hazard ratio of 1.01 (95% CI, 0.81-1.25; P = .95).

Het volledige studierapport: Monthly High-Dose Vitamin D Supplementation and Cancer Risk is tegen betaling in te zien.

Hier het abstract van de studie:

High-dose vitamin D supplementation prescribed monthly for up to 4 years without calcium may not prevent cancer. This study suggests that daily or weekly dosing for a longer period may require further study.

July 19, 2018

Monthly High-Dose Vitamin D Supplementation and Cancer RiskA Post Hoc Analysis of the Vitamin D Assessment Randomized Clinical Trial

Robert Scragg, MBBS, PhD¹; Kay-Tee Khaw, MBBChir, MSc²; Les Toop, MBChB, MD³; et al John Sluyter, PhD¹; Carlene M. M. Lawes, MBChB, PhD¹; Debbie Waayer, MEd¹; Edward Giovannucci, MD, ScD^4,5; Carlos A. Camargo Jr, MD, DrPH⁶

Author Affiliations

JAMA Oncol. Published online July 19, 2018. doi:10.1001/jamaoncol.2018.2178

Key Points

Question Is monthly high-dose vitamin D supplementation associated with cancer prevention?

Findings In this post hoc analysis of Vitamin D Assessment (ViDA) randomized clinical trial that included 5108 community adults in New Zealand, the cumulative incidence of cancer for a median follow-up period of 3.3 years was 6.5% among participants receiving 100 000 IU of vitamin D₃ monthly and 6.4% among participants receiving placebo.

Meaning Monthly high-dose vitamin D supplementation may not be associated with cancer preventionand should not be used for this purpose.

Abstract

Importance Previous randomized clinical trials have reported inconsistent results on the effect of vitamin D supplementation on cancer incidence.

Objective To examine whether high-dose vitamin D supplementation received monthly, without calcium, is associated with a reduction in cancer incidence and cancer mortality in the general population.

Design, Setting, and Participants This is a post hoc analysis of data from the Vitamin D Assessment (ViDA) study, a randomized, double-blind, placebo-controlled trial that recruited participants from family practices and community groups in Auckland, New Zealand, from April 5, 2011, through November 6, 2012, with follow-up completed December 31, 2015. Participants were adult community residents aged 50 to 84 years. Of 47 905 adults invited from family practices and 163 from community groups, 5110 participants were randomized to receive vitamin D₃ (n = 2558) or placebo (n = 2552). Two participants withdrew consent, and all others (n = 5108) were included in the primary analysis. Data analysis was by intention to treat.

Interventions Oral vitamin D₃, in an initial bolus dose of 200 000 IU and followed by monthly doses of 100 000 IU, or placebo for a median of 3.3 years (range, 2.5-4.2 years).

Main Outcomes and Measures Post hoc primary outcome was the number of all primary invasive and in situ malignant neoplasms (excluding nonmelanoma skin cancers) diagnosed from randomization until the study medication was discontinued on July 31, 2015.

Results Of the 5108 participants included in the analysis, the mean (SD) age was 65.9 (8.3) years, 58.1% were male, and 4253 (83.3%) were of European or another race/ethnicity, with the remainder being Polynesian or South Asian. Mean (SD) baseline deseasonalized 25-hydroxyvitamin D concentration was 26.5 (9.0) ng/mL. In a random sample of 438 participants, the mean follow-up 25-hydroxyvitamin D concentration consistently was greater than 20 ng/mL higher in the vitamin D group than in the placebo group. The primary outcome of cancer comprised 328 total cases of cancer (259 invasive and 69 in situ malignant neoplasms) and occurred in 165 of 2558 participants (6.5%) in the vitamin D group and 163 of 2550 (6.4%) in the placebo group, yielding an adjusted hazard ratio of 1.01 (95% CI, 0.81-1.25; P = .95).

Conclusions and Relevance High-dose vitamin D supplementation prescribed monthly for up to 4 years without calcium may not prevent cancer. This study suggests that daily or weekly dosing for a longer period may require further study.

Trial Registration anzctr.org.au Identifier: ACTRN12611000402943

vitamine D, 25-hydroxyvitamine D, bloedwaarden, kans op kanker, preventie, kankersoorten, alle vormen van kanker