Do you think contacts make a difference? I did some research on vitamin D a couple of years ago. I found that glass will filter out almost all of the light waves that help you make vitamin D. If you want light exposure for vitamin D production, you can't do it through a pane of glass.

I have really bad eye sight, so I almost always wear glasses or contacts. I wear glasses while I'm sitting in front of the light box. I do wonder sometimes if it makes a difference. I hope not.