Safety of long term supplementation with a large dose of vitamin D3

Abstract

Background: Many studies have been conducted on vitamin D supplementation within the past few decades. This has been in response to promising results of observational studies suggesting additional health benefits, beyond the previously suggested bone health, if desirable vitamin D levels achieved. As a result, a number of randomized controlled trials (RCTs) have given bolus doses of vitamin D to investigate the suggested health benefits. However, there is little data on the safety of long term large dose supplementation with vitamin D, particularly in the general population. Aims: This thesis aimed to investigate if there is any risk involved with long term (3-4 years) supplementation from a bolus dose of vitamin D3 in a RCT on 5110 middle-aged and older adults in Auckland, New Zealand.