Organic cotton clothing recommendations?

I feel like this topic fits better under wellness than fashion, so I’m dropping it here—but if you think it belongs somewhere else, just move it. Sorry if there’s already a thread for this.
So, does anyone know where I can find a clothing store in San Francisco that sells all-natural cotton? I'm specifically looking for underwear. It's a big deal for me.

Ma'am, please try posting your inquiry here or within one of the threads on the Fashion PDF.