Micronutrients & recovery
Higher baseline 25(OH)D concentrations result in a significantly smaller increase in serum 25(OH)D following vitamin D supplementation, demonstrating an inverse dose-response relationship.
If you are vitamin D deficient, you will likely see a much larger increase in your blood levels from supplementation than someone who is already sufficient. This is not a failure of the supplement, but a biological response to the saturable nature of liver enzymes. Deficient individuals should expect a robust response, while sufficient individuals may see minimal changes from standard doses.
change in 25(OH)D concentration had a significant inverse correlation with baseline 25(OH)D concentrations... The largest increase was seen in subjects in the first tertile (10–34 nmol/L)... followed by those in the second tertile (35–49 nmol/L) and then those in the third tertile (50–86 nmol/L)
Why this rating
Based on a systematic review of multiple intervention trials showing consistent inverse relationships, though some small studies failed to detect it.
Source
Factors Affecting 25-Hydroxyvitamin D Concentration in Response to Vitamin D Supplementation
Hajar Mazahery et al. · Nutrients · 2015
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