I have heard the same about sugars. In fact, I heard that PET scans actually measure sugar uptake to see where (or if) cancer concentrations exist. I try and limit my sugar intake, but can't say I am overly rigorous about it. Mostly if I do eat anything sweet I just feel guilty about it, so I try and stay away.
We also make most things from scratch so we avoid processed foods except in extreme cases.
I stopped eating red meat after I was diagnosed. We used to eat a lot of red meat and I figured it couldn't hurt. I think we did it mostly because it was something we could control at a time when we had so little control over so much. Probably much like an anorexic limits calories to get control I guess. We still do not eat red meat because heart disease runs in my husbands family and we just plain feel better without it. But I have to say that sometimes we eat so much chicken I feel like I should cluck instead of talk.
I also developed lactose intolerance, so I avoid dairy, but I do love me my cheese, so sometimes I just suffer the consequences or take the lactose pills.
I've tried to get on a vitamin regime too, but it messes so much with my digestion that I've given up for the moment.
I agree with Lainy that the "diet" or "low fat" things often have more sugar and sometimes salt then their full on counterparts. Best to read the labels and judge for yourself. Also watch out for things marked "healthy" or "organic" and the like, oftentimes it's just to get you to buy it and it really isn't healthy at all.
Survivor of breast cancer (1994), thyroid cancer (1999), cholangiocarcinoma (2009).
My comments, suggestions, and opinions are based only on my personal experience as a cancer survivor. Please consult a physician for professional guidance.