Request for invalidation from service

I'm working in a central government department in Chennai for 16.5 years. Initial 7 years of service, I was posted in a hectic, risky, travel oriented, day and night work, irregular sleep and food, I developed severe hypothyroiditis, hypertension, anxiety disorder, hyper acidity, depression, anemia and so on. These diseases are aggravated during the Service. I have some documents in support of this claim. As all the above problems are getting aggravated day by day, Now, i want to take VRS. But for VRS , minimum 20 years service is needed. But there is a provision of Medical invalidation in central Civil services rules, 1972. If I apply for that, i will be sent before 3 member Medical Board and they have to satisfy and to give percentage for my diseases. If they satisfy that these diseases are aggravated during service and attributable due to service, they may certify that I'm unfit for service, so that I can get VRS. And any prima facie there to prove my claim before Medical Board. Plz advice