Pharmaceutical companies aren't likely to invest millions studying turmeric, spirulina, chlorella, sunlight, etc. There are credible studies if you intentionally go looking for them, though.
Here are a few that may change your mind: http://jn.nutrition.org/cgi/content/full/137/1/233S http://www.annieappleseedproject.org/lifchancline.html http://bastyrcenter.org/content/view/913/
Surely you must admit that your claim that lifestyle change cannot reduce mortality rate is premature. It's only recently being studied, and with the great early results we will see many more such papers investigating the effects.
My money would be on a combination: Lifestyle change + aggressive supplementation + chemo.
"It just doesn't work" is a statement of fact. I showed you some research that refutes this (lifestyle change alone can cure in certain cases). What more do you need to change your opinion?
Frankly, I find your know-it-all arrogance shocking, and all that is wrong with the medicine. 90% of doctors I have worked with have the same mentality. If it's not studied, how can you come to a conclusion?
Here's one little extract to whet your appetite.
[edit: btw I am in no way advocating naturopathy, homeopathy or other well debunked shams]
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Men with early stage prostate cancer who make intensive changes in diet and lifestyle may stop or perhaps even reverse the progression of their illness, according to a new study.
The research is the first randomised, controlled trial showing that lifestyle changes may affect the progression of any type of cancer.
The research team behind the American study looked at 93 men with biopsy-proven prostate cancer who had elected not to undergo conventional treatment for reasons unrelated to this study. The participants were randomly divided into either a group who were asked to make comprehensive changes in diet and lifestyle or a comparison group who were not asked to do so.
Participants in the lifestyle-change group were placed on a vegan diet consisting primarily of fruits, vegetables, whole grains, and legumes supplemented with soy, vitamins and minerals. They participated in moderate aerobic exercise, yoga/meditation, and a weekly support group session. A registered dietitian was available for consultation, and a nurse case manager contacted the participants regularly.