The last time I took a casual glance at studied, it seemed that vitamin D deficiency was correlated with multiple health conditions; however, vitamin D supplem

The last time I took a casual glance at studied, it seemed that vitamin D deficiency was correlated with multiple health conditions; however, vitamin D supplementation had not clearly prevented or reversed those conditions. That is, this isn't like scurvy. A common hypothesis was that vitamin D status was a proxy for sun exposure and not a complete explanation for those health problems.