Ideally, people would have the opportunity to consult a nutritionist and plan a diet tailored to their individual needs.
I don't think diet alone can thwart the beast....but I believe it can influence it. At a minimum, going into the fight healthier gives you a better chance of completing treatment. Beyond that, there's plenty of evidence that diet influences a number of cancers, even if not HNC in particular (so far). Our bodies have demonstrated a climate hospitable to cancer, and diet, stress and exercise are factors we can control that have the potential to roll up the welcome mat, or at least lock the screen door.
I'm just learning about all this, but I personally find the studies purporting that diet can affect cancer compelling. In particular, it makes sense to me that reducing oxidative stress and inflammation can help my body fight off cancer. That's why I'm wondering specifically about an anti-cancer diet, as opposed to a generally healthy diet. Avoiding dairy, most meat and added sugar is a HUGE lifestyle change here at Chez Mama.... but then cancer is the biggest motivator I've ever had. I will also admit that it comforts me to think there are factors I can control.