Note that very high levels of vitamin D supplements are possibly linked to reduction of volumetric bone density[0]. Low levels make sense given most people are

Note that very high levels of vitamin D supplements are possibly linked to reduction of volumetric bone density[0]. Low levels make sense given most people are more housebound during the pandemic. [0] https://pubmed.ncbi.nlm.nih.gov/31454046/ https://pubmed.ncbi.nlm.nih.gov/31454046/ "Conclusions and relevance: Among healthy adults, treatment with vitamin D for 3 years at a dose of 4000 IU per day or 10 000 IU per day, compared with 400 IU per day, resulted in statistically significant lower radial BMD; tibial BMD was significantly lower only with the 10 000 IU per day dose. There were no significant differences in bone strength at either the radius or tibia. These findings do not support a benefit of high-dose vitamin D supplementation for bone health; further research would be needed to determine whether it is harmful."