I went to an eye doctor due to blurry vision and dry eyes last year; he suggested both Vitamin D and Demodex (which kills mites which live in eyelash follicle roots).
I took the blood test for Vitamin D (25-hydroxy) and I was something around 7, where the desired number is more like 20-50. Started taking 10k-20k IU of Vitamin D per day (plus K and also a range of other daily vitamins added at the same time), as well as a 4 or 8 dose course of demodex over 2-3 weeks, and both problems were resolved within a month. Apparently low D causes the cornea to sag so the lens itself is out of shape and thus astigmatic.
I took the blood test for Vitamin D (25-hydroxy) and I was something around 7, where the desired number is more like 20-50. Started taking 10k-20k IU of Vitamin D per day (plus K and also a range of other daily vitamins added at the same time), as well as a 4 or 8 dose course of demodex over 2-3 weeks, and both problems were resolved within a month. Apparently low D causes the cornea to sag so the lens itself is out of shape and thus astigmatic.