Is multiple sclerosis similar to cancer and can the relapse be prevented thro food n exercise?

Very different, yes: Multiple sclerosis is a very different disease than cancer, hardly similar at all. There is strong evidence that a diet low in saturated fat can significantly reduce relapse (though few doctors know this!)- see http://bit.Ly/18b7vee i am not aware of exercise being shown to help. Many with ms may actually have lyme disease- see http://bit.Ly/1dljaei ; http://bit.Ly/1gzgpkp.

Yes, it can help: Your best diet would be a low fat, low salt diet, and aerobic exercise is clearly advantageous. Vitamin d-3 supplements can reduce relapse incidence, MRI lesions and decrease disability. However, your best success is to be acquired by use of a potent med, such as Gilenya or tysabri (natalizumab).