Dr Professor Scott took blood tests to test me for arthritis (I was told dry eyes can be linked to arthritis). He also checked my vitamin D levels as I was also told that a lack of vitamin D can cause or worsen dry eyes.
My blood test results showed that I didn’t have arthritis but I did have a Vitamin D deficiency. Therefore, I was told to start taking Vitamin D3 tablets which would help as they were very strong. I have been taking these tablets ever since: 
Ellie's dry eye diary 