Good morning Alan,
For me, as an individual, I find that the more control I have in my life the better I cope. This includes diet and exercise, which feels especially relevant during treatment and makes me feel that I'm doing my bit rather than just being in the hands of doctors etc. My regime may have little or even no impact but then again it might. It does, however, help keep my head straight . I eat healthily, have recently cut back a lot on dairy, take vitamin D3 and aspirin, ordered Pomi T supplement, incorporate turmeric, black pepper and garlic in my food. I find all this easy to do. I've stopped taking the aspirin as I'm due to start SRT next week. I've posted before that we all do what we need to do ,and as you say none of this is conclusively proven . I drink about 6/8 pints a week but pub atmosphere has always been highly beneficial for my mental wellbeing !
Take care , Paul.