If you can, by all means, eat the "green" vegetables...they provide nutrients that will help you fight cancer (and are good for you otherwise).
For those undergoing radiation therapy and chemotherapy, I personally would take a HIGH quality (pharmaceutical grade) multivitamin/mineral, and other antioxidant enhancers, like grape seed extract. The vast majority of physicians will advise you adamantly against doing this be/c they think the antioxidant activity will interfere with the chemo and rad therapy. This has NEVER been proven, and in fact several scientific studies have shown that use of nutritionals during these therapies minimized the NEGATIVE side effects, AND kept the patients healthier overall. I personally had to confront my father's doctor about this when my dad was going through chemo and rad. therapy for lung cancer. My dad, of course, yielded to what the physician said, not me, since I'm not one, and lived a horrible quality of life during his treatments, and for months after. To this day, he will not take nutritionals be/c his physician doesn't tell him to, and he doesn't like taking pills, so that's that.
For those who crave sweets, check with a health food store and get a natural sugar to substitute for the "white", refined sugar. You're right. Cancer cells THRIVE on sugar...that's the basis behind PET imaging. Patients are injected with a form of glucose tagged to a radioactive substance, and that is taken up readily by the cancer cells, even if a few cancer cells. They take an image, and see where the radioactivity is (or isn't) and are able to see very subtle areas because of this. That's why PET can detect cancer presence much more than other imaging modalities, like CT. Didn't mean to get off the subject, but thought you'd like to know that.
While I think you SHOULD consult someone about nutritional needs during a chronic illness, like cancer, be forewarned that most nutritionists and dieticians are of the same ilk as physicians when it comes to the use of nutritionals, and may not advise against the use of sugar in the diet be/c their philosophy is if that's all the patient can stomach, give it to him, even if it's also feeding the cancer. I don't understand the logic...again, they COULD advise to get a natural sugar substitute that won't do that, but I've never heard a nutritionist give that advise.
Having said all this understand that, as I indicated above, I'm not a physician. I also don't mean to sound as if I'm bashing physicians, because that's not my intent. However, the evidence that is mounting in the scientific arena for therapies other than drugs (i.e., chemo agents) needs to be circulated and discussed among physician circles. That won't happen as long as pharmaceutical companies are the main source of information to physicians about treatment options. And why should pharmaceutical companies provide nutritionals to keep people healthy? That would cut significantly into their drug profits. The system is driven by illness, not health, remember?
So, I'm not an MD, but I AM a health care professional who's made it my mission to seek out things that can be done to promote health, not just treat disease, so I'm self-taught on these matters. I DO keep up with the latest scientific literature, and I understand that there ARE numerous therapies that could be used to help people improve their specific conditions and overall health. Unfortunately, physicians aren't aware of them and/or rebuke them be/c they weren't part of their medical training. They also don't know HOW to treat the whole person, only the physical disease process.
I for one am working to change that, and you can, too, by how you spend your hard earned money to maintain your health. The public has already sent a loud message to the traditional medical system that they're willing to pay out of pocket for other therapies that will help them resolve their health issues. Practitioners in the traditional system are finally starting to listen be/c it's making a financial mark on their income, which is already being hit hard from other sides.
Didn't mean to post a diatribe, but I'm passionate about helping people stay healthy, and hope this information is helpful to someone.