The link between cancer and diet is a much-studied, mysterious one, say researchers. Many studies have pointed to foods that either seem to prevent or exacerbate cancer growth. But the research has been mostly inconclusive.
Studies have pointed to associations between certain foods and cancer, according to Harvard Health, not a cause-and-effect relationship.
"It's not 100 percent certain that consuming more or less of certain foods or nutrients will guarantee cancer protection," says Dr. Edward Giovannucci of Harvard's T.H. Chan School of Public Health. "But science has found that certain dietary habits tend to have a greater influence."
According to the World Cancer Research Fund, about 40 percent of all cancer casesare preventable. Among other things, changes in diet, physical fitness, inactivity, body weight, and alcohol and cigarette consumption may all play a part.

Anti-angiogenic foods

When Kathy Mydlach-Bero was diagnosed with two late-stage rare cancers more than a dozen years ago, the Wisconsin woman tried conventional treatments, including surgery, chemotherapy and radiation, but the cancer kept winning.
"My kidneys were failing; my liver was failing," Mydlach-Bero told WISN. "My lungs were damaged. My heart was damaged. I told my oncologist that I’m done with that protocol because one way or another, I’m going to die. And I don’t want to go that way."
A friend suggested she learn more about anti-angiogenic foods. These are foods that are believed to prevent the growth of harmful blood vessels that feed cancer and allow it to spread. They cover a range of fruits and vegetables, as well as plenty of herbs, nuts and some grass-fed meats and wild-caught seafood.
Mydlach-Bero says she combined her new diet with reiki energy healing, meditation and visualization. And it worked.
"My doctors just kept saying, 'Huh. That is interesting,'" she said.
Now she works as a cancer coach and speaker and tells WISN that researchers at Harvard Medical School are studying her history, as well as others who've had unusual cancer-fighting success.

The role of angiogenesis

Angiogenesis is the formation of new blood vessels. Angiogenesis is key in the growth of cancers, according to the National Cancer Institute, because solid tumors depend on a blood supply to grow. Tumors can also emit chemical signals that stimulate angiogenesis. The new blood vessels that are formed end up feeding growing tumors, allowing them to enlarge and invade nearby tissue.
"But these blood vessels are also cancer's Achilles Heel. Cutting off a tumor’s blood supply starves it of oxygen and nutrients," according to the Eat to Beat Cancerwebsite, a global campaign offering information about the diet-cancer link.
Researchers have created medications called angiogenesis inhibitors, which block the angiogenesis process. These drugs work by preventing or slowing cancer growth by starving it of its blood supply.
The belief is that anti-angiogenic foods work in the same way.
Eat to Beat Cancer is an information hub supported by the Angiogenesis Foundation, a nonprofit focused on studying angiogenesis-based science to improve health.
That's Angiogenesis Foundation President Dr. William Li, above, discussing cancer-fighting foods in a TED Talk.
The group has identified more than 100 foods containing naturally occurring angiogenesis inhibitors. The foods listed offer details about scientific evidence, as well as recipes that highlight cancer-fighting ingredients.
"For each food type, we believe that there are different potencies within different strains and varietals," Li says in his TED Talk. "And we want to measure this because, well, while you're eating a strawberry or drinking tea, why not select the one that's most potent for preventing cancer?"