03/02/2026
โ๏ธ Can sunlight through glass give you vitamin D?
No โ sunlight coming through regular glass does not help your body make vitamin D.
Multiple medical sources confirm that UVB rays, the specific part of sunlight your skin needs to produce vitamin D, are blocked by standard window glass. biologyin... +1
Why?
โข Vitamin D production requires UVB (290โ320 nm).
โข Ordinary glass blocks almost all UVB.
โข UVA passes through glass, which can still cause skin aging and damage, but does nothing for vitamin D. thehealthy.com
So you can sit in a sunny window all day and feel warm, but your skin isnโt making vitamin D at all.
Are there exceptions?
A few specialty glasses (like certain greenhouse or quartz glass) let UVB through, but these are not used in homes, cars, or offices. thehealthy.com
---
๐ค๏ธ So how do you actually get vitamin D?
1. Direct outdoor sunlight
Even 10โ15 minutes of midday sun on arms/legs a few times a week can help, depending on skin tone and season. thehealthy.com
2. Food sources
โข Salmon, mackerel, sardines
โข Egg yolks
โข Fortified milk, cereals, orange juice biologyinsig...
3. Supplements
A reliable option for people in northern climates (hello Quebec winters).