Sigh, this comes up every few months. I'll share my humble opinion, take it for whatever meager value it may have. Maybe not PC, but here we are.
"Sugar feeds cancer". Well, of course it does,
every cell in your body lives on sugar. Glucose is the fuel for every cell. We're able to survive on a wide variety of foods because our bodies can even convert proteins into sugar. Starches are just sugar molecules zipped together, sort of a delivery system for packaged sugar molecules. (And yes I understand it's really all about
the production of ATP, so this is oversimplifying).
I hear of people diagnosed who suddenly decide they'll not eat any more sugar, therefore stopping the cancer. I doubt it highly. Cancers show up on scans based on glucose-based tracers, since cancers are highly metabolic. Of course they show up.
If you reduce dietary sugars, they'll just get glucose on demand through your bloodstream's normal levels from somewhere else in your body or diet.
Your body has many feedback systems to make sure the cells get the glucose they need. You're not going to "starve" the tumors without catastrophic results throughout your body. Ask any diabetic what happens when their blood sugar level drops too low. That glucose blood fuel level is kept in a tightly controlled level by your own body, between 70 (fasting) -140 (post meal) mg/dl or so. Through severe diet restrictions, hugging the bottom of that range isn't going to cure cancer. Insulin does increase to control blood sugar levels, which is one mechanism speculated to be problematic for cancer.
Higher insulin levels are found in some cancers. Insulin seems to be some sort of growth factor. Some suggest increased insulin therefore causes cancers to grow. There's a lot of speculation and correlation, and "increase of risk" for some specific cancers, but far from settled science. That's the one area I see some possible effect, but mostly this is based on population occurrence rates related to diabetic treatment strategies. Nothing about
affecting the progress of existing disease.
Check out
Myth #4 from Cancer Research UK.
It seems to me a couple of things are going on. People are desperate for something they can do, something they can CONTROL in the face of an unpredictable, implacable monster. If all I can do is wait for the next PSA check, it's very uncomfortable. So, in the meantime, I'll CHANGE MY DIET, something I can CONTROL, and so feel that I'm "Doing Something" about
it.
Secondly, people make money through grants and books. Grants come from grant proposals, and studies come through grants, and books come from studies. Doesn't really matter how sound the underlying science may be, it's all about
greasing the money conveyor. Oh, and people get paid by advertisers by the click counts on websites; sensational click-bait web links = profit.
Finally, cancer terrifies people. Those who don't have it like the idea of "sugar feeds cancer". That way, they can smooth their mental feathers by convincing themselves if they ever did get diagnosed, well, why all they have to do is avoid cupcakes and cinnamon buns to conquer that rascally cancer.
Avoid excessive sugar to avoid excessive calories and the risks associated with obesity. Sure. Fine. But if you're here on this forum, diagnosed with PCa as most of us here, then I'm quite convinced that skipping the Frosted Flakes isn't going to affect your Prostate Cancer Specific Mortality prognosis.
I'm bringing donuts into work Friday, and I'm going to enjoy a kreme-filled chocolate long john very much. Life is short. Drink the wine. Order the dessert. Eat the donut.