Vitamin D is produced in the skin after exposure to UVB. These are the light bulbs we use.
This is not a UVB lamp, so not for vitamin D production, but it definitely helps with darkness-induced health problems, including SAD. We have those as well.
These tests test for vitamin D status. They can be ordered on line and shipped to the laboratory for analysis. No doctor visit required. Results via email.
We don’t use supplements, but that does not mean you mustn’t either. Here are our picks. PS. always take you vitamin D with fat and don’t exceed 4,000 IU a day. Use it only if you are deficient and only in times when the sunlight and diet cannot supply its adequate amounts. Supplements aren’t toys. Use with respect. More is not better.