From the publication:
Published in Annals of Internal Medicine, the study found that the more severe the vitamin D deficiency, the greater the risk of mortality.
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“Our study provides strong evidence for the connection between low levels of vitamin D and mortality, and this is the first study of its kind to also include respiratory disease related mortality as an outcome.
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The Mendelian randomization study evaluated 307,601 records from the UK Biobank. Low levels of vitamin D were noted as less than <25 nmol/L with the average concentration found to be 45.2 nmol/L. Over a 14-year follow up period, researchers found that the risk for death significantly decreased with increased vitamin D concentrations, with the strongest effects seen among those with severe deficiencies.