It also depends on the form. As others here note, Vit D is fat soluble so gel caps are much better. 1400 IU may not be enough especially if it's a pill. I take

It also depends on the form. As others here note, Vit D is fat soluble so gel caps are much better. 1400 IU may not be enough especially if it's a pill. I take a 5000 IU gel cap most days. Still, if you haven't been tested, you should. It's easy and inexpensive.