I cannot find the link to a site where the lady running the site talks about her mother dying from cancer. In it she makes the statement that most people starve because the cancer eats so much glucose the body is forced to catabolize (break down) protein to make glucose, rather than dying directly from the cancer. So you will have to accept my word that there is a site saying such. However, it is logical, since we know cancer feeds on glucose ravenously, that would lower the blood glucose level causing the body to attempt to raise it to keep it within the acceptable range. Unless there is carbohydrate stores in the digestive tract that can be drawn upon, the body will catabolize protein (muscles) to make glucose and when much of the muscle tissue has been used up - death. So being sure to provide lots of protein to save the muscles (heart is a muscle) from being "eaten" is important.
Here is one site I did find that you might read.
Cancer Cells Preferentially use Sugars.
Cancer's Sweet Tooth
http://www.annieappleseedproject.org/cansweettoot.html
[Excerpts from the above web site, out of the book "Beating Cancer with
Nutrition" by Patrick Quillin, PHD, RD, CNS. ]
During the last 10 years I have worked with more than 500 cancer patients as
director of nutrition for Cancer Treatment Centers of America in Tulsa, Okla.
It puzzles me why the simple concept "sugar feeds cancer" can be so dramatically
overlooked as part of a comprehensive cancer treatment plan.
The 1931 Nobel laureate in medicine, German Otto Warburg, Ph.D., first discovered
that cancer cells have a fundamentally different energy metabolism compared to
healthy cells.
In Europe, the "sugar feeds cancer" concept is so well accepted that oncologists,
or cancer doctors, use the Systemic Cancer Multistep Therapy (SCMT) protocol.