Reader Comments

Post a new comment on this article

Data in the paper show that vitamin D reduces risk of cancer death

Posted by wbgrant on 01 Jan 2018 at 23:35 GMT

While the authors stated that there was no significant linear association between 25-hydroxyvitamin D [25(OH)D] and cancer mortality, careful inspection of their data indicates otherwise. When the adjusted hazard ratios (HRs) for Model 4 of Table 4 were recalculated assuming that the value for 25(OH)D concentration >100 nmol should be set to 1.00 by multiplying all values by 1/0.79 = 1.26, and then the HRs and the 95% confidence intervals (CIs) plotted vs. 25(OH)D concentration for each of the six categories, the linear fit to the lower 95% CI rose above 1.0 near 90 nmol/l. Only one lower CI for 25(OH)D below 90 nmol/l fell below 1.0, that for the lowest 25(OH)D category.

That then brings the results of this study into agreement with a large body of peer-reviewed journal literature reporting that higher solar UVB exposure and 25(OH)D concentrations significantly reduce incidence and death from many types of cancer [1, 2].

1. Moukayed M, Grant WB. Molecular link between vitamin D and cancer prevention. Nutrients. 2013;5:3993-4023. doi: 10.3390/nu5103993

2, Moukayed M, Grant WB. The roles of UVB and vitamin D in reducing risk of cancer incidence and mortality: a review of the epidemiology, clinical trials, and mechanisms. Rev Endocr Metab Disord. June 2017;18(2):167–82. doi: 10.1007/s11154-017-9415-2

Competing interests declared: I receive funding from Bio-Tech Pharmacal (Fayetteville, AR)