For some people, this is a serious business. Mary McCue was diagnosed with breast cancer four years ago. The cancer changed her life and Mary changed her lifestyle.
"Ever since I had breast cancer...every food item I eat, I'm looking for maximum benefit," said McCue. "I took out sugars. I learned very quickly that's an inflammatory and that's not good for people who have cancer."
Rebecca Katz, head chef at several cancer centers, says certain foods can maximize cancer treatments, minimize side effects and improve outcomes. One of her favorites surprisingly is mint.
"It has photochemical that is really good at turning what I call the master cancer cell off," said Katz.
Her other top picks: cabbage, broccoli and cauliflower.
"You can create an environment in the body with the food that you eat to create what we call an inhospitable environment for cancer cells to grow," said she said.
They are known as functional foods, meaning they contain compounds thought to offer additional benefits. And it's not just about fighting cancer.
Newer research finds eating folate found in black-eyed peas, Vitamin E in almonds and Omega 3 fatty acids in salmon may lower your risk of Alzheimer's disease. Healthy proteins like lean chicken, salmon, tuna, nuts, beans and soy may help fight depression.
Retired researcher Phyllis Bowen, Ph.D and R.D., was studying functional foods at the University of Illinois at Chicago long before they were diet superstars.
"I think the story is eat five fruits and vegetables a day," said Bowen. "This doesn't have to be all broccoli. It can be fun things."
For example, dark chocolate may help lower high blood pressure and choosing brown rice over white could protect against diabetes. Research shows richly colored vegetables and fruits can help fight cancer, but there are some others raising interest.
"Citrus foods, especially lemons, have a lot of fioflavonoids in them...and it's especially concentrated in the skin," said Bowen.
How about mushrooms? The darker ones may hold a healthy secret.
"There's more research on the shitake and portabella mushroom as having maybe some bioactive ingredients especially for cancer," said Bowen.
When it comes to tea, one cup a day may not be enough to reap the possible heart and cancer benefits.
"Looking at the polyphenols that get in our blood stream, they don't last there very long. So you need to drink tea all day long," said Bowen.
Even the smallest changes may not only increase your health odds but leave you feeling younger.
"I was 56 when I was diagnosed and I felt like I was going on 70. Now I feel like I'm about 40 years old," said McCue.
Researchers stress there isn't a single element in a particular food that does all the work. Experts say it's best to aim for a balanced diet that includes a variety of foods.